Revert "yay"

This reverts commit 6ae4158762.

.buildkite/Dockerfile

@@ -1,12 +1,12 @@
-ARG LLVM_VERSION="18"
-ARG REPORTED_LLVM_VERSION="18.1.8"
+ARG LLVM_VERSION="19"
+ARG REPORTED_LLVM_VERSION="19.1.7"
 ARG OLD_BUN_VERSION="1.1.38"
 ARG DEFAULT_CFLAGS="-mno-omit-leaf-frame-pointer -fno-omit-frame-pointer -ffunction-sections -fdata-sections -faddrsig -fno-unwind-tables -fno-asynchronous-unwind-tables"
 ARG DEFAULT_CXXFLAGS="-flto=full -fwhole-program-vtables -fforce-emit-vtables"
 ARG BUILDKITE_AGENT_TAGS="queue=linux,os=linux,arch=${TARGETARCH}"
 
 FROM --platform=$BUILDPLATFORM ubuntu:20.04 as base-arm64
-FROM --platform=$BUILDPLATFORM ubuntu:18.04 as base-amd64
+FROM --platform=$BUILDPLATFORM ubuntu:20.04 as base-amd64
 FROM base-$TARGETARCH as base
 
 ARG LLVM_VERSION

.buildkite/ci.mjs

@@ -107,9 +107,9 @@ const buildPlatforms = [
   { os: "linux", arch: "aarch64", distro: "amazonlinux", release: "2023", features: ["docker"] },
   { os: "linux", arch: "x64", distro: "amazonlinux", release: "2023", features: ["docker"] },
   { os: "linux", arch: "x64", baseline: true, distro: "amazonlinux", release: "2023", features: ["docker"] },
-  { os: "linux", arch: "aarch64", abi: "musl", distro: "alpine", release: "3.20" },
-  { os: "linux", arch: "x64", abi: "musl", distro: "alpine", release: "3.20" },
-  { os: "linux", arch: "x64", abi: "musl", baseline: true, distro: "alpine", release: "3.20" },
+  { os: "linux", arch: "aarch64", abi: "musl", distro: "alpine", release: "3.21" },
+  { os: "linux", arch: "x64", abi: "musl", distro: "alpine", release: "3.21" },
+  { os: "linux", arch: "x64", abi: "musl", baseline: true, distro: "alpine", release: "3.21" },
   { os: "windows", arch: "x64", release: "2019" },
   { os: "windows", arch: "x64", baseline: true, release: "2019" },
 ];
@@ -134,9 +134,9 @@ const testPlatforms = [
   { os: "linux", arch: "x64", baseline: true, distro: "ubuntu", release: "24.04", tier: "latest" },
   { os: "linux", arch: "x64", baseline: true, distro: "ubuntu", release: "22.04", tier: "previous" },
   { os: "linux", arch: "x64", baseline: true, distro: "ubuntu", release: "20.04", tier: "oldest" },
-  { os: "linux", arch: "aarch64", abi: "musl", distro: "alpine", release: "3.20", tier: "latest" },
-  { os: "linux", arch: "x64", abi: "musl", distro: "alpine", release: "3.20", tier: "latest" },
-  { os: "linux", arch: "x64", abi: "musl", baseline: true, distro: "alpine", release: "3.20", tier: "latest" },
+  { os: "linux", arch: "aarch64", abi: "musl", distro: "alpine", release: "3.21", tier: "latest" },
+  { os: "linux", arch: "x64", abi: "musl", distro: "alpine", release: "3.21", tier: "latest" },
+  { os: "linux", arch: "x64", abi: "musl", baseline: true, distro: "alpine", release: "3.21", tier: "latest" },
   { os: "windows", arch: "x64", release: "2019", tier: "oldest" },
   { os: "windows", arch: "x64", release: "2019", baseline: true, tier: "oldest" },
 ];

.buildkite/scripts/upload-release.sh

@@ -201,6 +201,8 @@ function create_release() {
   local artifacts=(
     bun-darwin-aarch64.zip
     bun-darwin-aarch64-profile.zip
+    bun-darwin-x64.zip
+    bun-darwin-x64-profile.zip
     bun-linux-aarch64.zip
     bun-linux-aarch64-profile.zip
     bun-linux-x64.zip

.github/workflows/clang-format.yml

@@ -11,8 +11,8 @@ on:
 
 env:
   BUN_VERSION: "1.2.0"
-  LLVM_VERSION: "18.1.8"
-  LLVM_VERSION_MAJOR: "18"
+  LLVM_VERSION: "19.1.7"
+  LLVM_VERSION_MAJOR: "19"
 
 jobs:
   clang-format:

.github/workflows/clang-tidy.yml

@@ -11,8 +11,8 @@ on:
 
 env:
   BUN_VERSION: "1.2.0"
-  LLVM_VERSION: "18.1.8"
-  LLVM_VERSION_MAJOR: "18"
+  LLVM_VERSION: "19.1.7"
+  LLVM_VERSION_MAJOR: "19"
 
 jobs:
   clang-tidy:

.github/workflows/run-lint.yml

@@ -3,7 +3,6 @@ name: Lint
 permissions:
   contents: read
 env:
-  LLVM_VERSION: 16
   BUN_VERSION: "1.2.0"
 
 on:

.github/workflows/update-cares.yml

@@ -89,4 +89,6 @@ jobs:
 
             Updates c-ares to version ${{ steps.check-version.outputs.tag }}
 
+            Compare: https://github.com/c-ares/c-ares/compare/${{ steps.check-version.outputs.current }}...${{ steps.check-version.outputs.latest }}
+
             Auto-updated by [this workflow](https://github.com/oven-sh/bun/actions/workflows/update-cares.yml)

.github/workflows/update-libarchive.yml

@@ -89,4 +89,6 @@ jobs:
 
             Updates libarchive to version ${{ steps.check-version.outputs.tag }}
 
+            Compare: https://github.com/libarchive/libarchive/compare/${{ steps.check-version.outputs.current }}...${{ steps.check-version.outputs.latest }}
+
             Auto-updated by [this workflow](https://github.com/oven-sh/bun/actions/workflows/update-libarchive.yml)

.github/workflows/update-libdeflate.yml

@@ -89,4 +89,6 @@ jobs:
 
             Updates libdeflate to version ${{ steps.check-version.outputs.tag }}
 
+            Compare: https://github.com/ebiggers/libdeflate/compare/${{ steps.check-version.outputs.current }}...${{ steps.check-version.outputs.latest }}
+
             Auto-updated by [this workflow](https://github.com/oven-sh/bun/actions/workflows/update-libdeflate.yml)

.github/workflows/update-lolhtml.yml

@@ -89,4 +89,6 @@ jobs:
 
             Updates lolhtml to version ${{ steps.check-version.outputs.tag }}
 
+            Compare: https://github.com/cloudflare/lol-html/compare/${{ steps.check-version.outputs.current }}...${{ steps.check-version.outputs.latest }}
+
             Auto-updated by [this workflow](https://github.com/oven-sh/bun/actions/workflows/update-lolhtml.yml)

.github/workflows/update-lshpack.yml

@@ -89,4 +89,6 @@ jobs:
 
             Updates lshpack to version ${{ steps.check-version.outputs.tag }}
 
+            Compare: https://github.com/litespeedtech/ls-hpack/compare/${{ steps.check-version.outputs.current }}...${{ steps.check-version.outputs.latest }}
+
             Auto-updated by [this workflow](https://github.com/oven-sh/bun/actions/workflows/update-lshpack.yml)

.github/workflows/update-sqlite3.yml

@@ -106,4 +106,6 @@ jobs:
 
             Updates SQLite to version ${{ steps.check-version.outputs.latest }}
 
+            Compare: https://sqlite.org/src/vdiff?from=${{ steps.check-version.outputs.current }}&to=${{ steps.check-version.outputs.latest }}
+
             Auto-updated by [this workflow](https://github.com/oven-sh/bun/actions/workflows/update-sqlite3.yml)

.lldbinit

@@ -1,4 +1,16 @@
-# command script import vendor/zig/tools/lldb_pretty_printers.py
-command script import vendor/WebKit/Tools/lldb/lldb_webkit.py
+# Tell LLDB what to do when the debugged process receives SIGPWR: pass it through to the process
+# (-p), but do not stop the process (-s) or notify the user (-n).
+#
+# JSC's garbage collector sends this signal (as configured by Bun WebKit in
+# Thread::initializePlatformThreading() in ThreadingPOSIX.cpp) to the JS thread to suspend or resume
+# it. So stopping the process would just create noise when debugging any long-running script.
+process handle -p true -s false -n false SIGPWR
 
-# type summary add --summary-string "${var} | inner=${var[0-30]}, source=${var[33-64]}, tag=${var[31-32]}" "unsigned long"
+command script import misctools/lldb/lldb_pretty_printers.py
+type category enable zig.lang
+type category enable zig.std
+
+command script import misctools/lldb/lldb_webkit.py
+
+command script delete btjs
+command alias btjs p {printf("gathering btjs trace...\n");printf("%s\n", (char*)dumpBtjsTrace())}

.vscode/launch.json

@@ -22,7 +22,6 @@
       },
       "console": "internalConsole",
       // Don't pause when the GC runs while the debugger is open.
-      "postRunCommands": ["command source '${workspaceFolder}/misctools/lldb/lldb_commands'"],
     },
     {
       "type": "lldb",
@@ -38,7 +37,6 @@
       },
       "console": "internalConsole",
       // Don't pause when the GC runs while the debugger is open.
-      "postRunCommands": ["command source '${workspaceFolder}/misctools/lldb/lldb_commands'"],
     },
     {
       "type": "lldb",
@@ -60,7 +58,6 @@
       },
       "console": "internalConsole",
       // Don't pause when the GC runs while the debugger is open.
-      "postRunCommands": ["command source '${workspaceFolder}/misctools/lldb/lldb_commands'"],
     },
     {
       "type": "lldb",
@@ -76,7 +73,6 @@
       },
       "console": "internalConsole",
       // Don't pause when the GC runs while the debugger is open.
-      "postRunCommands": ["command source '${workspaceFolder}/misctools/lldb/lldb_commands'"],
     },
     {
       "type": "lldb",
@@ -92,7 +88,6 @@
       },
       "console": "internalConsole",
       // Don't pause when the GC runs while the debugger is open.
-      "postRunCommands": ["command source '${workspaceFolder}/misctools/lldb/lldb_commands'"],
     },
     {
       "type": "lldb",
@@ -108,7 +103,6 @@
       },
       "console": "internalConsole",
       // Don't pause when the GC runs while the debugger is open.
-      "postRunCommands": ["command source '${workspaceFolder}/misctools/lldb/lldb_commands'"],
     },
     {
       "type": "lldb",
@@ -125,7 +119,6 @@
       },
       "console": "internalConsole",
       // Don't pause when the GC runs while the debugger is open.
-      "postRunCommands": ["command source '${workspaceFolder}/misctools/lldb/lldb_commands'"],
       "serverReadyAction": {
         "pattern": "https://debug.bun.sh/#localhost:([0-9]+)/",
         "uriFormat": "https://debug.bun.sh/#ws://localhost:%s/",
@@ -147,7 +140,6 @@
       },
       "console": "internalConsole",
       // Don't pause when the GC runs while the debugger is open.
-      "postRunCommands": ["command source '${workspaceFolder}/misctools/lldb/lldb_commands'"],
       "serverReadyAction": {
         "pattern": "https://debug.bun.sh/#localhost:([0-9]+)/",
         "uriFormat": "https://debug.bun.sh/#ws://localhost:%s/",
@@ -169,7 +161,6 @@
       },
       "console": "internalConsole",
       // Don't pause when the GC runs while the debugger is open.
-      "postRunCommands": ["command source '${workspaceFolder}/misctools/lldb/lldb_commands'"],
     },
     {
       "type": "lldb",
@@ -188,7 +179,6 @@
       },
       "console": "internalConsole",
       // Don't pause when the GC runs while the debugger is open.
-      "postRunCommands": ["command source '${workspaceFolder}/misctools/lldb/lldb_commands'"],
     },
     {
       "type": "lldb",
@@ -203,7 +193,6 @@
       },
       "console": "internalConsole",
       // Don't pause when the GC runs while the debugger is open.
-      "postRunCommands": ["command source '${workspaceFolder}/misctools/lldb/lldb_commands'"],
     },
     {
       "type": "lldb",
@@ -221,7 +210,6 @@
       },
       "console": "internalConsole",
       // Don't pause when the GC runs while the debugger is open.
-      "postRunCommands": ["command source '${workspaceFolder}/misctools/lldb/lldb_commands'"],
     },
     {
       "type": "lldb",
@@ -236,7 +224,6 @@
       },
       "console": "internalConsole",
       // Don't pause when the GC runs while the debugger is open.
-      "postRunCommands": ["command source '${workspaceFolder}/misctools/lldb/lldb_commands'"],
     },
     {
       "type": "lldb",
@@ -253,7 +240,6 @@
       },
       "console": "internalConsole",
       // Don't pause when the GC runs while the debugger is open.
-      "postRunCommands": ["command source '${workspaceFolder}/misctools/lldb/lldb_commands'"],
       "serverReadyAction": {
         "pattern": "https://debug.bun.sh/#localhost:([0-9]+)/",
         "uriFormat": "https://debug.bun.sh/#ws://localhost:%s/",
@@ -275,7 +261,6 @@
       },
       "console": "internalConsole",
       // Don't pause when the GC runs while the debugger is open.
-      "postRunCommands": ["command source '${workspaceFolder}/misctools/lldb/lldb_commands'"],
       "serverReadyAction": {
         "pattern": "https://debug.bun.sh/#localhost:([0-9]+)/",
         "uriFormat": "https://debug.bun.sh/#ws://localhost:%s/",
@@ -297,7 +282,6 @@
       },
       "console": "internalConsole",
       // Don't pause when the GC runs while the debugger is open.
-      "postRunCommands": ["command source '${workspaceFolder}/misctools/lldb/lldb_commands'"],
     },
     {
       "type": "lldb",
@@ -313,7 +297,6 @@
       },
       "console": "internalConsole",
       // Don't pause when the GC runs while the debugger is open.
-      "postRunCommands": ["command source '${workspaceFolder}/misctools/lldb/lldb_commands'"],
     },
     {
       "type": "lldb",
@@ -329,7 +312,6 @@
       },
       "console": "internalConsole",
       // Don't pause when the GC runs while the debugger is open.
-      "postRunCommands": ["command source '${workspaceFolder}/misctools/lldb/lldb_commands'"],
     },
     {
       "type": "lldb",
@@ -345,7 +327,6 @@
       },
       "console": "internalConsole",
       // Don't pause when the GC runs while the debugger is open.
-      "postRunCommands": ["command source '${workspaceFolder}/misctools/lldb/lldb_commands'"],
     },
     {
       "type": "lldb",
@@ -361,7 +342,6 @@
       },
       "console": "internalConsole",
       // Don't pause when the GC runs while the debugger is open.
-      "postRunCommands": ["command source '${workspaceFolder}/misctools/lldb/lldb_commands'"],
     },
     {
       "type": "lldb",
@@ -378,7 +358,6 @@
       },
       "console": "internalConsole",
       // Don't pause when the GC runs while the debugger is open.
-      "postRunCommands": ["command source '${workspaceFolder}/misctools/lldb/lldb_commands'"],
       "serverReadyAction": {
         "pattern": "https://debug.bun.sh/#localhost:([0-9]+)/",
         "uriFormat": "https://debug.bun.sh/#ws://localhost:%s/",
@@ -400,7 +379,6 @@
       },
       "console": "internalConsole",
       // Don't pause when the GC runs while the debugger is open.
-      "postRunCommands": ["command source '${workspaceFolder}/misctools/lldb/lldb_commands'"],
       "serverReadyAction": {
         "pattern": "https://debug.bun.sh/#localhost:([0-9]+)/",
         "uriFormat": "https://debug.bun.sh/#ws://localhost:%s/",
@@ -421,7 +399,6 @@
       },
       "console": "internalConsole",
       // Don't pause when the GC runs while the debugger is open.
-      "postRunCommands": ["command source '${workspaceFolder}/misctools/lldb/lldb_commands'"],
     },
     // bun test [*]
     {
@@ -437,7 +414,6 @@
       },
       "console": "internalConsole",
       // Don't pause when the GC runs while the debugger is open.
-      "postRunCommands": ["command source '${workspaceFolder}/misctools/lldb/lldb_commands'"],
     },
     {
       "type": "lldb",
@@ -452,7 +428,6 @@
       },
       "console": "internalConsole",
       // Don't pause when the GC runs while the debugger is open.
-      "postRunCommands": ["command source '${workspaceFolder}/misctools/lldb/lldb_commands'"],
     },
     {
       "type": "lldb",
@@ -468,7 +443,6 @@
       },
       "console": "internalConsole",
       // Don't pause when the GC runs while the debugger is open.
-      "postRunCommands": ["command source '${workspaceFolder}/misctools/lldb/lldb_commands'"],
       "serverReadyAction": {
         "pattern": "https://debug.bun.sh/#localhost:([0-9]+)/",
         "uriFormat": "https://debug.bun.sh/#ws://localhost:%s/",
@@ -488,7 +462,6 @@
       },
       "console": "internalConsole",
       // Don't pause when the GC runs while the debugger is open.
-      "postRunCommands": ["command source '${workspaceFolder}/misctools/lldb/lldb_commands'"],
     },
     {
       "type": "lldb",
@@ -503,7 +476,6 @@
       },
       "console": "internalConsole",
       // Don't pause when the GC runs while the debugger is open.
-      "postRunCommands": ["command source '${workspaceFolder}/misctools/lldb/lldb_commands'"],
     },
     // Windows: bun test [file]
     {
@@ -1129,7 +1101,17 @@
       ],
       "console": "internalConsole",
       // Don't pause when the GC runs while the debugger is open.
-      "postRunCommands": ["command source '${workspaceFolder}/misctools/lldb/lldb_commands'"],
+    },
+    {
+      "type": "bun",
+      "name": "[JS] bun test [file]",
+      "runtime": "${workspaceFolder}/build/debug/bun-debug",
+      "runtimeArgs": ["test", "${file}"],
+      "cwd": "${workspaceFolder}",
+      "env": {
+        "BUN_DEBUG_QUIET_LOGS": "1",
+        "BUN_GARBAGE_COLLECTOR_LEVEL": "2",
+      },
     },
     {
       "type": "midas-rr",

CONTRIBUTING.md

@@ -80,7 +80,7 @@ $ sudo zypper install clang18 lld18 llvm18
 
 {% /codetabs %}
 
-If none of the above solutions apply, you will have to install it [manually](https://github.com/llvm/llvm-project/releases/tag/llvmorg-18.1.8).
+If none of the above solutions apply, you will have to install it [manually](https://github.com/llvm/llvm-project/releases/tag/llvmorg-19.1.7).
 
 Make sure Clang/LLVM 18 is in your path:
 
@@ -205,18 +205,30 @@ WebKit is not cloned by default (to save time and disk space). To clone and buil
 # Clone WebKit into ./vendor/WebKit
 $ git clone https://github.com/oven-sh/WebKit vendor/WebKit
 
+# Check out the commit hash specified in `set(WEBKIT_VERSION <commit_hash>)` in cmake/tools/SetupWebKit.cmake
+$ git -C vendor/WebKit checkout <commit_hash>
+
 # Make a debug build of JSC. This will output build artifacts in ./vendor/WebKit/WebKitBuild/Debug
 # Optionally, you can use `make jsc` for a release build
-$ make jsc-debug
+$ make jsc-debug && rm vendor/WebKit/WebKitBuild/Debug/JavaScriptCore/DerivedSources/inspector/InspectorProtocolObjects.h
 
 # Build bun with the local JSC build
 $ bun run build:local
 ```
 
+Using `bun run build:local` will build Bun in the `./build/debug-local` directory (instead of `./build/debug`), you'll have to change a couple of places to use this new directory:
+
+- The first line in [`src/js/builtins.d.ts`](/src/js/builtins.d.ts)
+- The `CompilationDatabase` line in [`.clangd` config](/.clangd) should be `CompilationDatabase: build/debug-local`
+- In [`build.zig`](/build.zig), the `codegen_path` option should be `build/debug-local/codegen` (instead of `build/debug/codegen`)
+- In [`.vscode/launch.json`](/.vscode/launch.json), many configurations use `./build/debug/`, change them as you see fit
+
 Note that the WebKit folder, including build artifacts, is 8GB+ in size.
 
 If you are using a JSC debug build and using VScode, make sure to run the `C/C++: Select a Configuration` command to configure intellisense to find the debug headers.
 
+Note that if you change make changes to our [WebKit fork](https://github.com/oven-sh/WebKit), you will also have to change [`SetupWebKit.cmake`](/cmake/tools/SetupWebKit.cmake) to point to the commit hash.
+
 ## Troubleshooting
 
 ### 'span' file not found on Ubuntu

LATEST

@@ -1 +1 @@
-1.2.4
+1.2.5

Makefile

@@ -91,9 +91,9 @@ ZIG ?= $(shell which zig 2>/dev/null || echo -e "error: Missing zig. Please make
 # This is easier to happen than you'd expect.
 # Using realpath here causes issues because clang uses clang++ as a symlink
 # so if that's resolved, it won't build for C++
-REAL_CC = $(shell which clang-18 2>/dev/null || which clang 2>/dev/null)
-REAL_CXX = $(shell which clang++-18 2>/dev/null || which clang++ 2>/dev/null)
-CLANG_FORMAT = $(shell which clang-format-18 2>/dev/null || which clang-format 2>/dev/null)
+REAL_CC = $(shell which clang-19 2>/dev/null || which clang 2>/dev/null)
+REAL_CXX = $(shell which clang++-19 2>/dev/null || which clang++ 2>/dev/null)
+CLANG_FORMAT = $(shell which clang-format-19 2>/dev/null || which clang-format 2>/dev/null)
 
 CC = $(REAL_CC)
 CXX = $(REAL_CXX)
@@ -117,14 +117,14 @@ CC_WITH_CCACHE = $(CCACHE_PATH) $(CC)
 ifeq ($(OS_NAME),darwin)
 # Find LLVM
 	ifeq ($(wildcard $(LLVM_PREFIX)),)
-		LLVM_PREFIX = $(shell brew --prefix llvm@18)
+		LLVM_PREFIX = $(shell brew --prefix llvm@19)
 	endif
 	ifeq ($(wildcard $(LLVM_PREFIX)),)
 		LLVM_PREFIX = $(shell brew --prefix llvm)
 	endif
 	ifeq ($(wildcard $(LLVM_PREFIX)),)
 #   This is kinda ugly, but I can't find a better way to error :(
-		LLVM_PREFIX = $(shell echo -e "error: Unable to find llvm. Please run 'brew install llvm@18' or set LLVM_PREFIX=/path/to/llvm")
+		LLVM_PREFIX = $(shell echo -e "error: Unable to find llvm. Please run 'brew install llvm@19' or set LLVM_PREFIX=/path/to/llvm")
 	endif
 
 	LDFLAGS += -L$(LLVM_PREFIX)/lib
@@ -164,7 +164,7 @@ CMAKE_FLAGS_WITHOUT_RELEASE = -DCMAKE_C_COMPILER=$(CC) \
 	-DCMAKE_OSX_DEPLOYMENT_TARGET=$(MIN_MACOS_VERSION) \
 	$(CMAKE_CXX_COMPILER_LAUNCHER_FLAG) \
 	-DCMAKE_AR=$(AR) \
-	-DCMAKE_RANLIB=$(which llvm-18-ranlib 2>/dev/null || which llvm-ranlib 2>/dev/null) \
+	-DCMAKE_RANLIB=$(which llvm-19-ranlib 2>/dev/null || which llvm-ranlib 2>/dev/null) \
 	-DCMAKE_CXX_STANDARD=20 \
 	-DCMAKE_C_STANDARD=17 \
 	-DCMAKE_CXX_STANDARD_REQUIRED=ON \
@@ -191,7 +191,7 @@ endif
 
 ifeq ($(OS_NAME),linux)
 LIBICONV_PATH =
-AR = $(shell which llvm-ar-18 2>/dev/null || which llvm-ar 2>/dev/null || which ar 2>/dev/null)
+AR = $(shell which llvm-ar-19 2>/dev/null || which llvm-ar 2>/dev/null || which ar 2>/dev/null)
 endif
 
 OPTIMIZATION_LEVEL=-O3 $(MARCH_NATIVE)
@@ -255,7 +255,7 @@ DEFAULT_LINKER_FLAGS= -pthread -ldl
 endif
 ifeq ($(OS_NAME),darwin)
     _MIMALLOC_OBJECT_FILE = 0
-	JSC_BUILD_STEPS += jsc-build-mac jsc-copy-headers
+	JSC_BUILD_STEPS += jsc-build-mac
 	JSC_BUILD_STEPS_DEBUG += jsc-build-mac-debug
 	_MIMALLOC_FILE = libmimalloc.a
 	_MIMALLOC_INPUT_PATH = libmimalloc.a
@@ -286,7 +286,7 @@ STRIP=/usr/bin/strip
 endif
 
 ifeq ($(OS_NAME),linux)
-STRIP=$(shell which llvm-strip 2>/dev/null || which llvm-strip-18 2>/dev/null || which strip 2>/dev/null || echo "Missing strip")
+STRIP=$(shell which llvm-strip 2>/dev/null || which llvm-strip-19 2>/dev/null || which strip 2>/dev/null || echo "Missing strip")
 endif
 
 
@@ -674,7 +674,7 @@ endif
 .PHONY: assert-deps
 assert-deps:
 	@echo "Checking if the required utilities are available..."
-	@if [ $(CLANG_VERSION) -lt "18" ]; then echo -e "ERROR: clang version >=18 required, found: $(CLANG_VERSION). Install with:\n\n    $(POSIX_PKG_MANAGER) install llvm@18"; exit 1; fi
+	@if [ $(CLANG_VERSION) -lt "19" ]; then echo -e "ERROR: clang version >=19 required, found: $(CLANG_VERSION). Install with:\n\n    $(POSIX_PKG_MANAGER) install llvm@19"; exit 1; fi
 	@cmake --version >/dev/null 2>&1 || (echo -e "ERROR: cmake is required."; exit 1)
 	@$(PYTHON) --version >/dev/null 2>&1 || (echo -e "ERROR: python is required."; exit 1)
 	@$(ESBUILD) --version >/dev/null 2>&1 || (echo -e "ERROR: esbuild is required."; exit 1)
@@ -924,7 +924,7 @@ bun-codesign-release-local-debug:
 
 
 .PHONY: jsc
-jsc: jsc-build jsc-copy-headers jsc-bindings
+jsc: jsc-build
 .PHONY: jsc-debug
 jsc-debug: jsc-build-debug
 .PHONY: jsc-build

bench/crypto/diffie-hellman.mjs

@@ -0,0 +1,53 @@
+import crypto from "node:crypto";
+import { bench, run } from "../runner.mjs";
+
+// Pre-generate DH params to avoid including setup in benchmarks
+const dhSize = 1024; // Reduced from 2048 for faster testing
+const dh = crypto.createDiffieHellman(dhSize);
+const dhPrime = dh.getPrime();
+const dhGenerator = dh.getGenerator();
+
+// Classical Diffie-Hellman
+bench("DH - generateKeys", () => {
+  const alice = crypto.createDiffieHellman(dhPrime, dhGenerator);
+  return alice.generateKeys();
+});
+
+bench("DH - computeSecret", () => {
+  // Setup
+  const alice = crypto.createDiffieHellman(dhPrime, dhGenerator);
+  const aliceKey = alice.generateKeys();
+  const bob = crypto.createDiffieHellman(dhPrime, dhGenerator);
+  const bobKey = bob.generateKeys();
+
+  // Benchmark just the secret computation
+  return alice.computeSecret(bobKey);
+});
+
+// ECDH with prime256v1 (P-256)
+bench("ECDH-P256 - generateKeys", () => {
+  const ecdh = crypto.createECDH("prime256v1");
+  return ecdh.generateKeys();
+});
+
+bench("ECDH-P256 - computeSecret", () => {
+  // Setup
+  const alice = crypto.createECDH("prime256v1");
+  const aliceKey = alice.generateKeys();
+  const bob = crypto.createECDH("prime256v1");
+  const bobKey = bob.generateKeys();
+
+  // Benchmark just the secret computation
+  return alice.computeSecret(bobKey);
+});
+
+// ECDH with secp384r1 (P-384)
+bench("ECDH-P384 - computeSecret", () => {
+  const alice = crypto.createECDH("secp384r1");
+  const aliceKey = alice.generateKeys();
+  const bob = crypto.createECDH("secp384r1");
+  const bobKey = bob.generateKeys();
+  return alice.computeSecret(bobKey);
+});
+
+await run();

bench/crypto/ecdh-convert-key.mjs

@@ -0,0 +1,44 @@
+import crypto from "node:crypto";
+import { bench, run } from "../runner.mjs";
+
+function generateTestKeyPairs() {
+  const curves = crypto.getCurves();
+  const keys = {};
+
+  for (const curve of curves) {
+    const ecdh = crypto.createECDH(curve);
+    ecdh.generateKeys();
+
+    keys[curve] = {
+      compressed: ecdh.getPublicKey("hex", "compressed"),
+      uncompressed: ecdh.getPublicKey("hex", "uncompressed"),
+      instance: ecdh,
+    };
+  }
+
+  return keys;
+}
+
+const testKeys = generateTestKeyPairs();
+
+bench("ECDH key format - P256 compressed to uncompressed", () => {
+  const publicKey = testKeys["prime256v1"].compressed;
+  return crypto.ECDH.convertKey(publicKey, "prime256v1", "hex", "hex", "uncompressed");
+});
+
+bench("ECDH key format - P256 uncompressed to compressed", () => {
+  const publicKey = testKeys["prime256v1"].uncompressed;
+  return crypto.ECDH.convertKey(publicKey, "prime256v1", "hex", "hex", "compressed");
+});
+
+bench("ECDH key format - P384 compressed to uncompressed", () => {
+  const publicKey = testKeys["secp384r1"].compressed;
+  return crypto.ECDH.convertKey(publicKey, "secp384r1", "hex", "hex", "uncompressed");
+});
+
+bench("ECDH key format - P384 uncompressed to compressed", () => {
+  const publicKey = testKeys["secp384r1"].uncompressed;
+  return crypto.ECDH.convertKey(publicKey, "secp384r1", "hex", "hex", "compressed");
+});
+
+await run();

bench/crypto/hkdf.mjs

@@ -0,0 +1,50 @@
+import crypto from "node:crypto";
+import { bench, run } from "../runner.mjs";
+
+// Sample keys with different lengths
+const keys = {
+  short: "secret",
+  long: "this-is-a-much-longer-secret-aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",
+};
+
+// Test parameters
+const salts = ["", "salt"];
+const infos = ["", "info"];
+const hashes = ["sha256", "sha512"];
+const sizes = [10, 1024];
+
+// Benchmark sync HKDF
+for (const hash of hashes) {
+  for (const keyName of Object.keys(keys)) {
+    const key = keys[keyName];
+    for (const size of sizes) {
+      bench(`hkdfSync ${hash} ${keyName}-key ${size} bytes`, () => {
+        return crypto.hkdfSync(hash, key, "salt", "info", size);
+      });
+    }
+  }
+}
+
+// Benchmark different combinations of salt and info
+for (const salt of salts) {
+  for (const info of infos) {
+    bench(`hkdfSync sha256 with ${salt ? "salt" : "no-salt"} and ${info ? "info" : "no-info"}`, () => {
+      return crypto.hkdfSync("sha256", "secret", salt, info, 64);
+    });
+  }
+}
+
+// Benchmark async HKDF (using promises for cleaner benchmark)
+// Note: async benchmarks in Mitata require returning a Promise
+for (const hash of hashes) {
+  bench(`hkdf ${hash} async`, async () => {
+    return new Promise((resolve, reject) => {
+      crypto.hkdf(hash, "secret", "salt", "info", 64, (err, derivedKey) => {
+        if (err) reject(err);
+        else resolve(derivedKey);
+      });
+    });
+  });
+}
+
+await run();

bench/crypto/primes.mjs

@@ -0,0 +1,43 @@
+import { checkPrime, checkPrimeSync, generatePrime, generatePrimeSync } from "node:crypto";
+import { bench, run } from "../runner.mjs";
+
+const prime512 = generatePrimeSync(512);
+const prime2048 = generatePrimeSync(2048);
+
+bench("checkPrimeSync 512", () => {
+  return checkPrimeSync(prime512);
+});
+
+bench("checkPrimeSync 2048", () => {
+  return checkPrimeSync(prime2048);
+});
+
+bench("checkPrime 512", async () => {
+  const promises = Array.from({ length: 10 }, () => new Promise(resolve => checkPrime(prime512, resolve)));
+  await Promise.all(promises);
+});
+
+bench("checkPrime 2048", async () => {
+  const promises = Array.from({ length: 10 }, () => new Promise(resolve => checkPrime(prime2048, resolve)));
+  await Promise.all(promises);
+});
+
+bench("generatePrimeSync 512", () => {
+  return generatePrimeSync(512);
+});
+
+bench("generatePrimeSync 2048", () => {
+  return generatePrimeSync(2048);
+});
+
+bench("generatePrime 512", async () => {
+  const promises = Array.from({ length: 10 }, () => new Promise(resolve => generatePrime(512, resolve)));
+  await Promise.all(promises);
+});
+
+bench("generatePrime 2048", async () => {
+  const promises = Array.from({ length: 10 }, () => new Promise(resolve => generatePrime(2048, resolve)));
+  await Promise.all(promises);
+});
+
+await run();

bench/crypto/random.mjs

@@ -0,0 +1,50 @@
+import crypto from "crypto";
+import { bench, run } from "../runner.mjs";
+
+bench("randomInt - sync", () => {
+  crypto.randomInt(1000);
+});
+
+bench("randomInt - async", async () => {
+  const { promise, resolve } = Promise.withResolvers();
+  crypto.randomInt(1000, () => {
+    resolve();
+  });
+  await promise;
+});
+
+bench("randonBytes - 32", () => {
+  crypto.randomBytes(32);
+});
+
+bench("randomBytes - 256", () => {
+  crypto.randomBytes(256);
+});
+
+const buf = Buffer.alloc(256);
+
+bench("randomFill - 32", async () => {
+  const { promise, resolve } = Promise.withResolvers();
+  crypto.randomFill(buf, 0, 32, () => {
+    resolve();
+  });
+  await promise;
+});
+
+bench("randomFill - 256", async () => {
+  const { promise, resolve } = Promise.withResolvers();
+  crypto.randomFill(buf, 0, 256, () => {
+    resolve();
+  });
+  await promise;
+});
+
+bench("randomFillSync - 32", () => {
+  crypto.randomFillSync(buf, 0, 32);
+});
+
+bench("randomFillSync - 256", () => {
+  crypto.randomFillSync(buf, 0, 256);
+});
+
+await run();

bench/package.json

@@ -12,6 +12,7 @@
     "eventemitter3": "^5.0.0",
     "execa": "^8.0.1",
     "fast-glob": "3.3.1",
+    "fastify": "^5.0.0",
     "fdir": "^6.1.0",
     "mitata": "^1.0.25",
     "react": "^18.3.1",

bench/snippets/express-hello.mjs

@@ -0,0 +1,13 @@
+import express from "express";
+
+const app = express();
+const port = 3000;
+
+var i = 0;
+app.get("/", (req, res) => {
+  res.send("Hello World!" + i++);
+});
+
+app.listen(port, () => {
+  console.log(`Express app listening at http://localhost:${port}`);
+});

bench/snippets/fastify.mjs

@@ -0,0 +1,20 @@
+import Fastify from "fastify";
+
+const fastify = Fastify({
+  logger: false,
+});
+
+fastify.get("/", async (request, reply) => {
+  return { hello: "world" };
+});
+
+const start = async () => {
+  try {
+    await fastify.listen({ port: 3000 });
+  } catch (err) {
+    fastify.log.error(err);
+    process.exit(1);
+  }
+};
+
+start();

build.zig

@@ -19,17 +19,17 @@ const OperatingSystem = @import("src/env.zig").OperatingSystem;
 const pathRel = fs.path.relative;
 
 /// Do not rename this constant. It is scanned by some scripts to determine which zig version to install.
-const recommended_zig_version = "0.14.0-dev.2987+183bb8b08";
+const recommended_zig_version = "0.14.0";
 
 comptime {
     if (!std.mem.eql(u8, builtin.zig_version_string, recommended_zig_version)) {
         @compileError(
             "" ++
-                "Bun requires Zig version " ++ recommended_zig_version ++ " (found " ++
-                builtin.zig_version_string ++ "). This is " ++
-                "automatically configured via Bun's CMake setup. You likely meant to run " ++
-                "`bun setup`. If you are trying to upgrade the Zig compiler, " ++
-                "run `./scripts/download-zig.sh master` or comment this message out.",
+                "Bun requires Zig version " ++ recommended_zig_version ++ ", but you have " ++
+                builtin.zig_version_string ++ ". This is automatically configured via Bun's " ++
+                "CMake setup. You likely meant to run `bun run build`. If you are trying to " ++
+                "upgrade the Zig compiler, edit ZIG_COMMIT in cmake/tools/SetupZig.cmake or " ++
+                "comment this error out.",
         );
     }
 }
@@ -319,7 +319,21 @@ pub fn build(b: *Build) !void {
             .{ .os = .linux, .arch = .aarch64 },
             .{ .os = .linux, .arch = .x86_64, .musl = true },
             .{ .os = .linux, .arch = .aarch64, .musl = true },
-        });
+        }, &.{ .Debug, .ReleaseFast });
+    }
+
+    // zig build check-all-debug
+    {
+        const step = b.step("check-all-debug", "Check for semantic analysis errors on all supported platforms in debug mode");
+        addMultiCheck(b, step, build_options, &.{
+            .{ .os = .windows, .arch = .x86_64 },
+            .{ .os = .mac, .arch = .x86_64 },
+            .{ .os = .mac, .arch = .aarch64 },
+            .{ .os = .linux, .arch = .x86_64 },
+            .{ .os = .linux, .arch = .aarch64 },
+            .{ .os = .linux, .arch = .x86_64, .musl = true },
+            .{ .os = .linux, .arch = .aarch64, .musl = true },
+        }, &.{.Debug});
     }
 
     // zig build check-windows
@@ -327,21 +341,21 @@ pub fn build(b: *Build) !void {
         const step = b.step("check-windows", "Check for semantic analysis errors on Windows");
         addMultiCheck(b, step, build_options, &.{
             .{ .os = .windows, .arch = .x86_64 },
-        });
+        }, &.{ .Debug, .ReleaseFast });
     }
     {
         const step = b.step("check-macos", "Check for semantic analysis errors on Windows");
         addMultiCheck(b, step, build_options, &.{
             .{ .os = .mac, .arch = .x86_64 },
             .{ .os = .mac, .arch = .aarch64 },
-        });
+        }, &.{ .Debug, .ReleaseFast });
     }
     {
         const step = b.step("check-linux", "Check for semantic analysis errors on Windows");
         addMultiCheck(b, step, build_options, &.{
             .{ .os = .linux, .arch = .x86_64 },
             .{ .os = .linux, .arch = .aarch64 },
-        });
+        }, &.{ .Debug, .ReleaseFast });
     }
 
     // zig build translate-c-headers
@@ -369,9 +383,10 @@ pub fn addMultiCheck(
     parent_step: *Step,
     root_build_options: BunBuildOptions,
     to_check: []const struct { os: OperatingSystem, arch: Arch, musl: bool = false },
+    optimize: []const std.builtin.OptimizeMode,
 ) void {
     for (to_check) |check| {
-        for ([_]std.builtin.Mode{ .Debug, .ReleaseFast }) |mode| {
+        for (optimize) |mode| {
             const check_target = b.resolveTargetQuery(.{
                 .os_tag = OperatingSystem.stdOSTag(check.os),
                 .cpu_arch = check.arch,

bunfig.node-test.toml

@@ -2,3 +2,7 @@
 # https://github.com/oven-sh/bun/issues/16289
 [test]
 preload = ["./test/js/node/harness.ts", "./test/preload.ts"]
+
+[install]
+# Node.js never auto-installs modules.
+auto = "disable"

cmake/Globals.cmake

@@ -419,7 +419,15 @@ function(register_command)
     list(APPEND CMD_EFFECTIVE_OUTPUTS ${artifact})
     if(BUILDKITE)
       file(RELATIVE_PATH filename ${BUILD_PATH} ${artifact})
-      list(APPEND CMD_COMMANDS COMMAND ${CMAKE_COMMAND} -E chdir ${BUILD_PATH} buildkite-agent artifact upload ${filename})
+      if(filename STREQUAL "libbun-profile.a")
+        # libbun-profile.a is now over 5gb in size, compress it first
+        list(APPEND CMD_COMMANDS COMMAND ${CMAKE_COMMAND} -E chdir ${BUILD_PATH} rm -r ${BUILD_PATH}/codegen)
+        list(APPEND CMD_COMMANDS COMMAND ${CMAKE_COMMAND} -E chdir ${BUILD_PATH} rm -r ${CACHE_PATH})
+        list(APPEND CMD_COMMANDS COMMAND ${CMAKE_COMMAND} -E chdir ${BUILD_PATH} gzip -6 libbun-profile.a)
+        list(APPEND CMD_COMMANDS COMMAND ${CMAKE_COMMAND} -E chdir ${BUILD_PATH} buildkite-agent artifact upload libbun-profile.a.gz)
+      else()
+        list(APPEND CMD_COMMANDS COMMAND ${CMAKE_COMMAND} -E chdir ${BUILD_PATH} buildkite-agent artifact upload ${filename})
+      endif()
     endif()
   endforeach()
 

cmake/targets/BuildBun.cmake

@@ -738,7 +738,7 @@ endif()
 # --- C/C++ Properties ---
 
 set_target_properties(${bun} PROPERTIES
-  CXX_STANDARD 20
+  CXX_STANDARD 23
   CXX_STANDARD_REQUIRED YES
   CXX_EXTENSIONS YES
   CXX_VISIBILITY_PRESET hidden
@@ -747,6 +747,18 @@ set_target_properties(${bun} PROPERTIES
   VISIBILITY_INLINES_HIDDEN YES
 )
 
+if (NOT WIN32)
+  # Enable precompiled headers
+  # Only enable in these scenarios:
+  # 1. NOT in CI, OR
+  # 2. In CI AND BUN_CPP_ONLY is enabled
+  if(NOT CI OR (CI AND BUN_CPP_ONLY))
+    target_precompile_headers(${bun} PRIVATE
+      "$<$<COMPILE_LANGUAGE:CXX>:${CWD}/src/bun.js/bindings/root.h>"
+    )
+  endif()
+endif()
+
 # --- C/C++ Includes ---
 
 if(WIN32)
@@ -901,6 +913,10 @@ if(NOT WIN32)
       -Werror
     )
   endif()
+else()
+  target_compile_options(${bun} PUBLIC
+    -Wno-nullability-completeness
+  )
 endif()
 
 # --- Linker options ---
@@ -943,28 +959,17 @@ endif()
 
 if(LINUX)
   if(NOT ABI STREQUAL "musl")
-  # on arm64
-  if(CMAKE_SYSTEM_PROCESSOR MATCHES "arm|ARM|arm64|ARM64|aarch64|AARCH64")
-    target_link_options(${bun} PUBLIC
-      -Wl,--wrap=exp
-      -Wl,--wrap=expf
-      -Wl,--wrap=fcntl64
-      -Wl,--wrap=log
-      -Wl,--wrap=log2
-      -Wl,--wrap=log2f
-      -Wl,--wrap=logf
-      -Wl,--wrap=pow
-      -Wl,--wrap=powf
-    )
-  else()
-    target_link_options(${bun} PUBLIC
-      -Wl,--wrap=exp
-      -Wl,--wrap=expf
-      -Wl,--wrap=log2f
-      -Wl,--wrap=logf
-      -Wl,--wrap=powf
-    )
-  endif()
+  target_link_options(${bun} PUBLIC
+    -Wl,--wrap=exp
+    -Wl,--wrap=expf
+    -Wl,--wrap=fcntl64
+    -Wl,--wrap=log
+    -Wl,--wrap=log2
+    -Wl,--wrap=log2f
+    -Wl,--wrap=logf
+    -Wl,--wrap=pow
+    -Wl,--wrap=powf
+  )
   endif()
 
   if(NOT ABI STREQUAL "musl")

cmake/targets/BuildLolHtml.cmake

@@ -4,7 +4,7 @@ register_repository(
   REPOSITORY
     cloudflare/lol-html
   COMMIT
-    4f8becea13a0021c8b71abd2dcc5899384973b66
+    67f1d4ffd6b74db7e053fb129dcce620193c180d
 )
 
 set(LOLHTML_CWD ${VENDOR_PATH}/lolhtml/c-api)

cmake/tools/SetupBuildkite.cmake

@@ -120,6 +120,9 @@ foreach(i RANGE ${BUILDKITE_JOBS_MAX_INDEX})
     endif()
 
     if(BUILDKITE)
+      if(BUILDKITE_ARTIFACT_PATH STREQUAL "libbun-profile.a")
+        set(BUILDKITE_ARTIFACT_PATH libbun-profile.a.gz)
+      endif()
       set(BUILDKITE_DOWNLOAD_COMMAND buildkite-agent artifact download ${BUILDKITE_ARTIFACT_PATH} . --build ${BUILDKITE_BUILD_UUID} --step ${BUILDKITE_JOB_ID})
     else()
       set(BUILDKITE_DOWNLOAD_COMMAND curl -L -o ${BUILDKITE_ARTIFACT_PATH} ${BUILDKITE_ARTIFACTS_URL}/${BUILDKITE_ARTIFACT_ID})
@@ -135,6 +138,20 @@ foreach(i RANGE ${BUILDKITE_JOBS_MAX_INDEX})
       OUTPUT
         ${BUILD_PATH}/${BUILDKITE_ARTIFACT_PATH}
     )
+    if(BUILDKITE_ARTIFACT_PATH STREQUAL "libbun-profile.a.gz")
+      add_custom_command(
+        COMMENT
+          "Unpacking libbun-profile.a.gz"
+        VERBATIM COMMAND
+          gunzip libbun-profile.a.gz
+        WORKING_DIRECTORY
+          ${BUILD_PATH}
+        OUTPUT
+          ${BUILD_PATH}/libbun-profile.a
+        DEPENDS
+          ${BUILD_PATH}/libbun-profile.a.gz
+      )
+    endif()
   endforeach()
 
   list(APPEND BUILDKITE_JOBS_MATCH ${BUILDKITE_JOB_NAME})

cmake/tools/SetupGit.cmake

@@ -36,7 +36,8 @@ endif()
 string(REPLACE "\n" ";" GIT_CHANGED_SOURCES "${GIT_DIFF}")
 
 if(CI)
-  setx(GIT_CHANGED_SOURCES ${GIT_CHANGED_SOURCES})
+  set(GIT_CHANGED_SOURCES "${GIT_CHANGED_SOURCES}")
+  message(STATUS "Set GIT_CHANGED_SOURCES: ${GIT_CHANGED_SOURCES}")
 endif()
 
 list(TRANSFORM GIT_CHANGED_SOURCES PREPEND ${CWD}/)

cmake/tools/SetupLLVM.cmake

@@ -12,7 +12,7 @@ if(NOT ENABLE_LLVM)
   return()
 endif()
 
-set(DEFAULT_LLVM_VERSION "18.1.8")
+set(DEFAULT_LLVM_VERSION "19.1.7")
 
 optionx(LLVM_VERSION STRING "The version of LLVM to use" DEFAULT ${DEFAULT_LLVM_VERSION})
 

cmake/tools/SetupWebKit.cmake

@@ -2,7 +2,7 @@ option(WEBKIT_VERSION "The version of WebKit to use")
 option(WEBKIT_LOCAL "If a local version of WebKit should be used instead of downloading")
 
 if(NOT WEBKIT_VERSION)
-  set(WEBKIT_VERSION 2be7f2f098210ce560f72ef95d93b008bc8eaaa1)
+  set(WEBKIT_VERSION 91bf2baced1b1309c7e05f19177c97fefec20976)
 endif()
 
 string(SUBSTRING ${WEBKIT_VERSION} 0 16 WEBKIT_VERSION_PREFIX)

cmake/tools/SetupZig.cmake

@@ -20,7 +20,7 @@ else()
   unsupported(CMAKE_SYSTEM_NAME)
 endif()
 
-set(ZIG_COMMIT "bb9d6ab2c0bbbf20cc24dad03e88f3b3ffdb7de7")
+set(ZIG_COMMIT "cd1995944508e4c946deb75bd70947d302e0db37")
 optionx(ZIG_TARGET STRING "The zig target to use" DEFAULT ${DEFAULT_ZIG_TARGET})
 
 if(CMAKE_BUILD_TYPE STREQUAL "Release")

docs/api/node-api.md

@@ -12,5 +12,3 @@ Alternatively, use `process.dlopen`:
 let mod = { exports: {} };
 process.dlopen(mod, "./my-node-module.node");
 ```
-
-Bun polyfills the [`detect-libc`](https://npmjs.com/package/detect-libc) package, which is used by many Node-API modules to detect which `.node` binding to `require`.

docs/api/s3.md

@@ -715,7 +715,7 @@ await S3Client.delete("my-file.txt", credentials);
 await S3Client.unlink("my-file.txt", credentials);
 ```
 
-## s3:// protocol
+## `s3://` protocol
 
 To make it easier to use the same code for local files and S3 files, the `s3://` protocol is supported in `fetch` and `Bun.file()`.
 

docs/api/spawn.md

@@ -77,6 +77,16 @@ console.log(text); // "const input = "hello world".repeat(400); ..."
 
 ---
 
+- `ReadableStream`
+- Use a readable stream as input.
+
+---
+
+- `Blob`
+- Use a blob as input.
+
+---
+
 - `number`
 - Read from the file with a given file descriptor.
 
@@ -129,13 +139,13 @@ Configure the output stream by passing one of the following values to `stdout/st
 
 ---
 
-- `Bun.file()`
-- Write to the specified file.
+- `"ignore"`
+- Discard the output.
 
 ---
 
-- `null`
-- Write to `/dev/null`.
+- `Bun.file()`
+- Write to the specified file.
 
 ---
 
@@ -174,7 +184,8 @@ const proc = Bun.spawn(["bun", "--version"]);
 proc.kill();
 proc.killed; // true
 
-proc.kill(); // specify an exit code
+proc.kill(15); // specify a signal code
+proc.kill("SIGTERM"); // specify a signal name
 ```
 
 The parent `bun` process will not terminate until all child processes have exited. Use `proc.unref()` to detach the child process from the parent.
@@ -184,6 +195,64 @@ const proc = Bun.spawn(["bun", "--version"]);
 proc.unref();
 ```
 
+## Resource usage
+
+You can get information about the process's resource usage after it has exited:
+
+```ts
+const proc = Bun.spawn(["bun", "--version"]);
+await proc.exited;
+
+const usage = proc.resourceUsage();
+console.log(`Max memory used: ${usage.maxRSS} bytes`);
+console.log(`CPU time (user): ${usage.cpuTime.user} µs`);
+console.log(`CPU time (system): ${usage.cpuTime.system} µs`);
+```
+
+## Using AbortSignal
+
+You can abort a subprocess using an `AbortSignal`:
+
+```ts
+const controller = new AbortController();
+const { signal } = controller;
+
+const proc = Bun.spawn({
+  cmd: ["sleep", "100"],
+  signal,
+});
+
+// Later, to abort the process:
+controller.abort();
+```
+
+## Using timeout and killSignal
+
+You can set a timeout for a subprocess to automatically terminate after a specific duration:
+
+```ts
+// Kill the process after 5 seconds
+const proc = Bun.spawn({
+  cmd: ["sleep", "10"],
+  timeout: 5000, // 5 seconds in milliseconds
+});
+
+await proc.exited; // Will resolve after 5 seconds
+```
+
+By default, timed-out processes are killed with the `SIGTERM` signal. You can specify a different signal with the `killSignal` option:
+
+```ts
+// Kill the process with SIGKILL after 5 seconds
+const proc = Bun.spawn({
+  cmd: ["sleep", "10"],
+  timeout: 5000,
+  killSignal: "SIGKILL", // Can be string name or signal number
+});
+```
+
+The `killSignal` option also controls which signal is sent when an AbortSignal is aborted.
+
 ## Inter-process communication (IPC)
 
 Bun supports direct inter-process communication channel between two `bun` processes. To receive messages from a spawned Bun subprocess, specify an `ipc` handler.
@@ -233,11 +302,17 @@ process.send("Hello from child as string");
 process.send({ message: "Hello from child as object" });
 ```
 
-The `ipcMode` option controls the underlying communication format between the two processes:
+The `serialization` option controls the underlying communication format between the two processes:
 
 - `advanced`: (default) Messages are serialized using the JSC `serialize` API, which supports cloning [everything `structuredClone` supports](https://developer.mozilla.org/en-US/docs/Web/API/Web_Workers_API/Structured_clone_algorithm). This does not support transferring ownership of objects.
 - `json`: Messages are serialized using `JSON.stringify` and `JSON.parse`, which does not support as many object types as `advanced` does.
 
+To disconnect the IPC channel from the parent process, call:
+
+```ts
+childProc.disconnect();
+```
+
 ### IPC between Bun & Node.js
 
 To use IPC between a `bun` process and a Node.js process, set `serialization: "json"` in `Bun.spawn`. This is because Node.js and Bun use different JavaScript engines with different object serialization formats.
@@ -310,7 +385,7 @@ spawnSync echo hi    1.47 ms/iter     (1.14 ms … 2.64 ms)   1.57 ms   2.37 ms
 
 ## Reference
 
-A simple reference of the Spawn API and types are shown below. The real types have complex generics to strongly type the `Subprocess` streams with the options passed to `Bun.spawn` and `Bun.spawnSync`. For full details, find these types as defined [bun.d.ts](https://github.com/oven-sh/bun/blob/main/packages/bun-types/bun.d.ts).
+A reference of the Spawn API and types are shown below. The real types have complex generics to strongly type the `Subprocess` streams with the options passed to `Bun.spawn` and `Bun.spawnSync`. For full details, find these types as defined [bun.d.ts](https://github.com/oven-sh/bun/blob/main/packages/bun-types/bun.d.ts).
 
 ```ts
 interface Bun {
@@ -329,16 +404,25 @@ interface Bun {
 namespace SpawnOptions {
   interface OptionsObject {
     cwd?: string;
-    env?: Record<string, string>;
-    stdin?: SpawnOptions.Readable;
-    stdout?: SpawnOptions.Writable;
-    stderr?: SpawnOptions.Writable;
-    onExit?: (
-      proc: Subprocess,
+    env?: Record<string, string | undefined>;
+    stdio?: [Writable, Readable, Readable];
+    stdin?: Writable;
+    stdout?: Readable;
+    stderr?: Readable;
+    onExit?(
+      subprocess: Subprocess,
       exitCode: number | null,
-      signalCode: string | null,
-      error: Error | null,
-    ) => void;
+      signalCode: number | null,
+      error?: ErrorLike,
+    ): void | Promise<void>;
+    ipc?(message: any, subprocess: Subprocess): void;
+    serialization?: "json" | "advanced";
+    windowsHide?: boolean;
+    windowsVerbatimArguments?: boolean;
+    argv0?: string;
+    signal?: AbortSignal;
+    timeout?: number;
+    killSignal?: string | number;
   }
 
   type Readable =
@@ -366,39 +450,62 @@ namespace SpawnOptions {
     | Request;
 }
 
-interface Subprocess<Stdin, Stdout, Stderr> {
+interface Subprocess extends AsyncDisposable {
+  readonly stdin: FileSink | number | undefined;
+  readonly stdout: ReadableStream<Uint8Array> | number | undefined;
+  readonly stderr: ReadableStream<Uint8Array> | number | undefined;
+  readonly readable: ReadableStream<Uint8Array> | number | undefined;
   readonly pid: number;
-  // the exact stream types here are derived from the generic parameters
-  readonly stdin: number | ReadableStream | FileSink | undefined;
-  readonly stdout: number | ReadableStream | undefined;
-  readonly stderr: number | ReadableStream | undefined;
-
   readonly exited: Promise<number>;
-
-  readonly exitCode: number | undefined;
-  readonly signalCode: Signal | null;
+  readonly exitCode: number | null;
+  readonly signalCode: NodeJS.Signals | null;
   readonly killed: boolean;
 
+  kill(exitCode?: number | NodeJS.Signals): void;
   ref(): void;
   unref(): void;
-  kill(code?: number): void;
+
+  send(message: any): void;
+  disconnect(): void;
+  resourceUsage(): ResourceUsage | undefined;
 }
 
-interface SyncSubprocess<Stdout, Stderr> {
-  readonly pid: number;
-  readonly success: boolean;
-  // the exact buffer types here are derived from the generic parameters
-  readonly stdout: Buffer | undefined;
-  readonly stderr: Buffer | undefined;
+interface SyncSubprocess {
+  stdout: Buffer | undefined;
+  stderr: Buffer | undefined;
+  exitCode: number;
+  success: boolean;
+  resourceUsage: ResourceUsage;
+  signalCode?: string;
+  exitedDueToTimeout?: true;
+  pid: number;
 }
 
-type ReadableSubprocess = Subprocess<any, "pipe", "pipe">;
-type WritableSubprocess = Subprocess<"pipe", any, any>;
-type PipedSubprocess = Subprocess<"pipe", "pipe", "pipe">;
-type NullSubprocess = Subprocess<null, null, null>;
+interface ResourceUsage {
+  contextSwitches: {
+    voluntary: number;
+    involuntary: number;
+  };
 
-type ReadableSyncSubprocess = SyncSubprocess<"pipe", "pipe">;
-type NullSyncSubprocess = SyncSubprocess<null, null>;
+  cpuTime: {
+    user: number;
+    system: number;
+    total: number;
+  };
+  maxRSS: number;
+
+  messages: {
+    sent: number;
+    received: number;
+  };
+  ops: {
+    in: number;
+    out: number;
+  };
+  shmSize: number;
+  signalCount: number;
+  swapCount: number;
+}
 
 type Signal =
   | "SIGABRT"

docs/api/tcp.md

@@ -11,7 +11,7 @@ Bun.listen({
   socket: {
     data(socket, data) {}, // message received from client
     open(socket) {}, // socket opened
-    close(socket) {}, // socket closed
+    close(socket, error) {}, // socket closed
     drain(socket) {}, // socket ready for more data
     error(socket, error) {}, // error handler
   },
@@ -30,7 +30,7 @@ Bun.listen({
     open(socket) {},
     data(socket, data) {},
     drain(socket) {},
-    close(socket) {},
+    close(socket, error) {},
     error(socket, error) {},
   },
 });
@@ -122,7 +122,7 @@ const socket = await Bun.connect({
   socket: {
     data(socket, data) {},
     open(socket) {},
-    close(socket) {},
+    close(socket, error) {},
     drain(socket) {},
     error(socket, error) {},
 

docs/project/building-windows.md

@@ -60,7 +60,7 @@ Visual Studio can be installed graphically using the wizard or through WinGet:
 
 After Visual Studio, you need the following:
 
-- LLVM 18.1.8
+- LLVM 19.1.7
 - Go
 - Rust
 - NASM
@@ -81,7 +81,7 @@ After Visual Studio, you need the following:
 > irm https://get.scoop.sh | iex
 > scoop install nodejs-lts go rust nasm ruby perl ccache
 # scoop seems to be buggy if you install llvm and the rest at the same time
-> scoop install llvm@18.1.8
+> scoop install llvm@19.1.7
 ```
 
 {% /codetabs %}

docs/runtime/nodejs-apis.md

@@ -174,7 +174,7 @@ Some methods are not optimized yet.
 
 ### [`node:test`](https://nodejs.org/api/test.html)
 
-🔴 Not implemented. Use [`bun:test`](https://bun.sh/docs/cli/test) instead.
+🟡 Partly implemented. Missing mocks, snapshots, timers. Use [`bun:test`](https://bun.sh/docs/cli/test) instead.
 
 ### [`node:trace_events`](https://nodejs.org/api/tracing.html)
 
@@ -346,7 +346,7 @@ The table below lists all globals implemented by Node.js and Bun's current compa
 
 ### [`process`](https://nodejs.org/api/process.html)
 
-🟡 Mostly implemented. `process.binding` (internal Node.js bindings some packages rely on) is partially implemented. `process.title` is a currently a no-op on macOS & Linux. `getActiveResourcesInfo` `setActiveResourcesInfo`, `getActiveResources` and `setSourceMapsEnabled` are stubs. Newer APIs like `process.loadEnvFile` and `process.getBuiltinModule` are not implemented yet.
+🟡 Mostly implemented. `process.binding` (internal Node.js bindings some packages rely on) is partially implemented. `process.title` is currently a no-op on macOS & Linux. `getActiveResourcesInfo` `setActiveResourcesInfo`, `getActiveResources` and `setSourceMapsEnabled` are stubs. Newer APIs like `process.loadEnvFile` and `process.getBuiltinModule` are not implemented yet.
 
 ### [`queueMicrotask()`](https://developer.mozilla.org/en-US/docs/Web/API/queueMicrotask)
 

docs/runtime/plugins.md

@@ -329,7 +329,7 @@ await Bun.build({
 
 {% callout %}
 
-**NOTE**: Plugin lifcycle callbacks (`onStart()`, `onResolve()`, etc.) do not have the ability to modify the `build.config` object in the `setup()` function. If you want to mutate `build.config`, you must do so directly in the `setup()` function:
+**NOTE**: Plugin lifecycle callbacks (`onStart()`, `onResolve()`, etc.) do not have the ability to modify the `build.config` object in the `setup()` function. If you want to mutate `build.config`, you must do so directly in the `setup()` function:
 
 ```ts
 await Bun.build({
@@ -400,7 +400,7 @@ type Loader = "js" | "jsx" | "ts" | "tsx" | "css" | "json" | "toml" | "object";
 
 ### Namespaces
 
-`onLoad` and `onResolve` accept an optional `namespace` string. What is a namespaace?
+`onLoad` and `onResolve` accept an optional `namespace` string. What is a namespace?
 
 Every module has a namespace. Namespaces are used to prefix the import in transpiled code; for instance, a loader with a `filter: /\.yaml$/` and `namespace: "yaml:"` will transform an import from `./myfile.yaml` into `yaml:./myfile.yaml`.
 

misctools/lldb/lldb_commands

@@ -1,13 +0,0 @@
-# Tell LLDB what to do when the debugged process receives SIGPWR: pass it through to the process
-# (-p), but do not stop the process (-s) or notify the user (-n).
-#
-# JSC's garbage collector sends this signal (as configured by Bun WebKit in
-# Thread::initializePlatformThreading() in ThreadingPOSIX.cpp) to the JS thread to suspend or resume
-# it. So stopping the process would just create noise when debugging any long-running script.
-process handle -p true -s false -n false SIGPWR
-
-command script import misctools/lldb/lldb_pretty_printers.py
-type category enable zig.lang
-type category enable zig.std
-
-command script import misctools/lldb/lldb_webkit.py

misctools/lldb/lldb_webkit.py

@@ -329,7 +329,7 @@ def btjs(debugger, command, result, internal_dict):
     addressFormat = '#0{width}x'.format(width=target.GetAddressByteSize() * 2 + 2)
     process = target.GetProcess()
     thread = process.GetSelectedThread()
-    jscModule = target.module["JavaScriptCore"]
+    jscModule = target.module["JavaScriptCore"] or target.module["bun"] or target.module["bun-debug"]
 
     if jscModule.FindSymbol("JSC::CallFrame::describeFrame").GetSize() or jscModule.FindSymbol("_ZN3JSC9CallFrame13describeFrameEv").GetSize():
         annotateJSFrames = True

package.json

@@ -1,7 +1,7 @@
 {
   "private": true,
   "name": "bun",
-  "version": "1.2.5",
+  "version": "1.2.6",
   "workspaces": [
     "./packages/bun-types"
   ],

packages/bun-plugin-svelte/README.md

@@ -8,7 +8,7 @@ The official [Svelte](https://svelte.dev/) plugin for [Bun](https://bun.sh/).
 ## Installation
 
 ```sh
-bun add -D bun-plugin-svelte
+$ bun add -D bun-plugin-svelte
 ```
 
 ## Dev Server Usage
@@ -16,52 +16,25 @@ bun add -D bun-plugin-svelte
 `bun-plugin-svelte` integrates with Bun's [Fullstack Dev Server](https://bun.sh/docs/bundler/fullstack), giving you
 HMR when developing your Svelte app.
 
-```html
-<!-- index.html -->
-<html>
-  <head>
-    <script type="module" src="./index.ts"></script>
-  </head>
-  <body>
-    <div id="root"></div>
-  </body>
-</html>
+Start by registering it in your [bunfig.toml](https://bun.sh/docs/runtime/bunfig):
+
+```toml
+[serve.static]
+plugins = ["bun-plugin-svelte"]
 ```
 
-```ts
-// index.ts
+Then start your dev server:
 
-import { mount, unmount } from "svelte";
-import App from "./App.svelte";
-
-// mount the application entrypoint to the DOM
-const root = document.getElementById("root")!;
-const app = mount(App, { target: root });
+```
+$ bun index.html
 ```
 
-```svelte
-<!-- App.svelte -->
-
-<script lang="ts">
-  // out-of-the-box typescript support
-  let name: string = "Bun";
-</script>
-
-<main class="app">
-  <h1>Cookin up apps with {name}</h1>
-</main>
-
-<style>
-  h1 {
-      color: #ff3e00;
-      text-align: center;
-      font-size: 2em;
-  }
-</style>
-```
+See the [example](https://github.com/oven-sh/bun/tree/main/packages/bun-plugin-svelte/example) for a complete example.
 
 ## Bundler Usage
 
+`bun-plugin-svelte` lets you bundle Svelte components with [`Bun.build`](https://bun.sh/docs/bundler).
+
 ```ts
 // build.ts
 // to use: bun run build.ts
@@ -70,7 +43,7 @@ import { SveltePlugin } from "bun-plugin-svelte"; // NOTE: not published to npm
 Bun.build({
   entrypoints: ["src/index.ts"],
   outdir: "dist",
-  target: "browser", // use "bun" or "node" to use Svelte components server-side
+  target: "browser",
   sourcemap: true, // sourcemaps not yet supported
   plugins: [
     SveltePlugin({
@@ -84,3 +57,13 @@ Bun.build({
 
 `bun-plugin-svelte` does not yet support server-side imports (e.g. for SSR).
 This will be added in the near future.
+
+## Not Yet Supported
+
+Support for these features will be added in the near future
+
+- Server-side imports/rendering
+- Source maps
+- CSS extensions (e.g. tailwind) in `<style>` blocks
+- TypeScript-specific features (e.g. enums and namespaces). If you're using
+  TypeScript 5.8, consider enabling [`--erasableSyntaxOnly`](https://devblogs.microsoft.com/typescript/announcing-typescript-5-8-beta/#the---erasablesyntaxonly-option)

packages/bun-plugin-svelte/example/App.svelte

@@ -0,0 +1,311 @@
+<script lang="ts">
+  import FeatureCard from "./FeatureCard.svelte";
+
+  const links = [
+    { text: "Bun Documentation", url: "https://bun.sh/docs" },
+    { text: "Svelte Documentation", url: "https://svelte.dev/docs" },
+    { text: "GitHub", url: "https://github.com/oven-sh/bun/tree/main/packages/bun-plugin-svelte" },
+  ];
+</script>
+
+<main>
+  <div class="hero">
+    <div class="logo-container">
+      <a href="https://bun.sh" class="bun-logo">
+        <img
+          src="https://github.com/user-attachments/assets/50282090-adfd-4ddb-9e27-c30753c6b161"
+          alt="Bun Logo"
+          height="42"
+        />
+      </a>
+    </div>
+    <h1><span class="highlight">bun-plugin-svelte</span></h1>
+    <p class="tagline">The official Svelte plugin for <a href="https://bun.sh" target="_blank">Bun</a></p>
+
+    <div class="cta-buttons">
+      <a href="https://bun.sh/docs/bundler/html" class="button primary">🚀 Get Started</a>
+      <a href="https://github.com/oven-sh/bun/tree/main/packages/bun-plugin-svelte/example" class="button secondary"
+        >👀 View Examples</a
+      >
+    </div>
+  </div>
+
+  <section class="usage">
+    <h2>🏃‍➡️ Quick Start</h2>
+
+    <div class="flex-grid">
+      <div>
+        <h3>1. Install from <a href="https://npmjs.com/package/bun-plugin-svelte" target="_blank">NPM</a></h3>
+        <pre><code class="language-bash">bun add -D bun-plugin-svelte</code></pre>
+      </div>
+      <div>
+        <h3>2. Add it to your <a href="https://bun.sh/docs/runtime/bunfig" target="_blank">bunfig.toml</a></h3>
+        <pre><code class="language-toml">
+[serve.static]
+plugins = ["bun-plugin-svelte"];
+        </code></pre>
+      </div>
+    </div>
+  </section>
+
+  <section class="features">
+    <h2>✨ Features</h2>
+    <div class="feature-grid">
+      <FeatureCard title="🔥 HMR Support" link="https://bun.sh/docs/bundler/html">
+        Integrates with Bun's Fullstack Dev Server for hot module replacement
+      </FeatureCard>
+      <FeatureCard title="📦 Bundling" link="https://bun.sh/docs/bundler">
+        Bundle Svelte components with <a href="https://bun.sh/docs/bundler">Bun.build</a>
+      </FeatureCard>
+    </div>
+
+    <section class="resources">
+      <h2>📖 Resources</h2>
+      <ul class="resource-links">
+        {#each links as link}
+          <li><a href={link.url} target="_blank" rel="noopener noreferrer">{link.text}</a></li>
+        {/each}
+      </ul>
+    </section>
+
+    <footer>
+      <p>Made with ❤️ by the Bun team</p>
+    </footer>
+  </section>
+</main>
+
+<style>
+  :global(body) {
+    margin: 0;
+    padding: 0;
+    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Oxygen, Ubuntu, Cantarell, "Open Sans",
+      "Helvetica Neue", sans-serif;
+    background-color: #f9f9f9;
+    color: #333;
+  }
+  :global(a) {
+    color: #ff3e00;
+    text-decoration: none;
+    position: relative;
+  }
+
+  :global(a::after) {
+    content: "";
+    position: absolute;
+    width: 100%;
+    height: 1px;
+    bottom: 0;
+    left: 0;
+    background-color: #ff3e00;
+    transform: scaleX(0);
+    transform-origin: bottom right;
+    transition: transform 0.3s ease-out;
+  }
+
+  :global(a:hover::after) {
+    transform: scaleX(1);
+    transform-origin: bottom left;
+  }
+
+  :global(a:visited) {
+    color: #ff3e00;
+  }
+
+  :global(pre > code.hljs) {
+    padding: 0;
+  }
+
+  main {
+    max-width: 1200px;
+    margin: 0 auto;
+    padding: 2rem;
+  }
+
+  .hero {
+    text-align: center;
+    padding: 3rem 1rem;
+    margin-bottom: 2rem;
+    display: flex;
+    flex-direction: column;
+  }
+
+  .logo-container {
+    margin-bottom: 1.5rem;
+    margin: auto 25%;
+  }
+
+  .bun-logo {
+    display: block;
+    transition: transform 0.3s ease;
+  }
+
+  .bun-logo:hover {
+    transform: scale(1.05);
+  }
+
+  .bun-logo img {
+    max-width: 33vw;
+    height: auto;
+  }
+
+  h1 {
+    font-size: 2.5rem;
+    margin-bottom: 0.5rem;
+  }
+
+  .highlight {
+    color: #ff3e00;
+    font-weight: bold;
+  }
+
+  /* Don't apply the underline effect to buttons and resource links */
+  .button::after,
+  .resource-links li a::after,
+  .bun-logo::after {
+    display: none;
+  }
+
+  .tagline {
+    font-size: 1.2rem;
+    color: #666;
+    margin-bottom: 2rem;
+  }
+
+  .cta-buttons {
+    display: flex;
+    justify-content: center;
+    gap: 1rem;
+    margin-bottom: 2rem;
+  }
+
+  .button {
+    display: inline-block;
+    padding: 0.8rem 1.5rem;
+    border-radius: 4px;
+    text-decoration: none;
+    font-weight: 600;
+    transition: all 0.2s ease;
+  }
+
+  .button.primary {
+    background-color: #ff3e00;
+    color: white;
+    box-shadow: 0 2px 10px rgba(255, 62, 0, 0.2);
+  }
+
+  .button.primary:hover {
+    background-color: #e63600;
+    transform: translateY(-2px);
+    box-shadow: 0 4px 12px rgba(255, 62, 0, 0.3);
+  }
+
+  .button.secondary {
+    background-color: #f0f0f0;
+    color: #333;
+    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
+  }
+
+  .button.secondary:hover {
+    background-color: #e6e6e6;
+    transform: translateY(-2px);
+    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
+  }
+
+  section {
+    margin-bottom: 3rem;
+    padding: 2rem;
+    background-color: white;
+    border-radius: 8px;
+    box-shadow: 0 2px 15px rgba(0, 0, 0, 0.05);
+  }
+
+  h2 {
+    font-size: 1.8rem;
+    margin-bottom: 1.5rem;
+    color: #333;
+    border-bottom: 2px solid #f0f0f0;
+    padding-bottom: 0.5rem;
+  }
+
+  .flex-grid {
+    display: flex;
+    gap: 1.5rem;
+  }
+  .flex-grid > div {
+    flex: 1;
+  }
+
+  .feature-grid {
+    display: grid;
+    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
+    gap: 1.5rem;
+    margin-bottom: 2rem;
+  }
+
+  pre {
+    background-color: #f5f5f5;
+    padding: 1rem;
+    border-radius: 4px;
+    overflow-x: auto;
+    font-family: "SFMono-Regular", Consolas, "Liberation Mono", Menlo, monospace;
+    font-size: 0.9rem;
+    line-height: 1.5;
+  }
+
+  code {
+    color: #333;
+  }
+
+  .resource-links {
+    list-style: none;
+    padding: 0;
+    display: flex;
+    flex-wrap: wrap;
+    gap: 1rem;
+  }
+
+  .resource-links li a {
+    display: inline-block;
+    padding: 0.5rem 1rem;
+    background-color: #f5f5f5;
+    color: #333;
+    text-decoration: none;
+    border-radius: 4px;
+    transition: all 0.2s ease;
+  }
+
+  .resource-links li a:hover {
+    background-color: #ff3e00;
+    color: white;
+    transform: translateY(-2px);
+  }
+
+  footer {
+    text-align: center;
+    padding: 2rem 0;
+    color: #666;
+    font-size: 0.9rem;
+  }
+
+  @media (max-width: 768px) {
+    .feature-grid {
+      grid-template-columns: 1fr;
+    }
+
+    .cta-buttons {
+      flex-direction: column;
+      align-items: center;
+    }
+
+    .button {
+      width: 100%;
+      max-width: 300px;
+      margin-bottom: 0.5rem;
+      text-align: center;
+    }
+
+    .resource-links {
+      flex-direction: column;
+    }
+  }
+</style>

packages/bun-plugin-svelte/example/FeatureCard.svelte

@@ -0,0 +1,28 @@
+<script lang="ts">
+  let { title, link, children } = $props();
+</script>
+
+<div class="feature-card">
+  <h3>
+    <a href={link}>
+      {title}
+    </a>
+  </h3>
+  <p>
+    {@render children()}
+  </p>
+</div>
+
+<style>
+  .feature-card {
+    padding: 1rem;
+    border-radius: 0.5rem;
+    background-color: #fff;
+    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
+    transition: transform 0.3s ease;
+  }
+
+  .feature-card h3 {
+    margin-bottom: 0.5rem;
+  }
+</style>

packages/bun-plugin-svelte/example/bunfig.toml

@@ -0,0 +1,2 @@
+[serve.static]
+plugins = ["bun-plugin-svelte"]

packages/bun-plugin-svelte/example/index.html

@@ -0,0 +1,25 @@
+<html>
+  <head>
+    <script type="module" src="./index.ts"></script>
+
+    <link rel="prefetch" href="https://bun.sh/docs/bundler/plugins" />
+    <link rel="preconnect" href="https://bun.sh" />
+    <link rel="preconnect" href="https://github.com" />
+
+    <link
+      rel="stylesheet"
+      href="https://cdn.jsdelivr.net/gh/highlightjs/cdn-release@11.9.0/build/styles/default.min.css"
+    />
+    <script src="https://cdn.jsdelivr.net/gh/highlightjs/cdn-release@11.9.0/build/highlight.min.js"></script>
+
+    <script src="https://cdn.jsdelivr.net/gh/highlightjs/cdn-release@11.9.0/build/languages/toml.min.js"></script>
+
+    <script>
+      hljs.highlightAll();
+    </script>
+  </head>
+
+  <body>
+    <div id="root"></div>
+  </body>
+</html>

packages/bun-plugin-svelte/example/index.ts

@@ -0,0 +1,29 @@
+import { mount, unmount } from "svelte";
+import App from "./App.svelte";
+
+declare global {
+  var didMount: boolean | undefined;
+  var hljs: any;
+}
+
+let app: Record<string, any> | undefined;
+
+// mount the application entrypoint to the DOM on first load. On subsequent hot
+// updates, the app will be unmounted and re-mounted via the accept handler.
+
+const root = document.getElementById("root")!;
+if (!globalThis.didMount) {
+  app = mount(App, { target: root });
+}
+globalThis.didMount = true;
+
+if (import.meta.hot) {
+  import.meta.hot.accept(async () => {
+    // avoid unmounting twice when another update gets accepted while outros are playing
+    if (!app) return;
+    const prevApp = app;
+    app = undefined;
+    await unmount(prevApp, { outro: true });
+    app = mount(App, { target: root });
+  });
+}

packages/bun-plugin-svelte/package.json

@@ -1,6 +1,14 @@
 {
   "name": "bun-plugin-svelte",
-  "version": "0.0.1",
+  "version": "0.0.5",
+  "description": "Official Svelte plugin for Bun",
+  "repository": {
+    "type": "git",
+    "url": "https://github.com/oven-sh/bun",
+    "directory": "packages/bun-plugin-svelte"
+  },
+  "homepage": "https://bun.sh",
+  "license": "MIT",
   "type": "module",
   "module": "src/index.ts",
   "index": "src/index.ts",
@@ -8,16 +16,18 @@
     ".": "./src/index.ts"
   },
   "scripts": {
+    "example": "bun --config=./example/bunfig.toml example/index.html",
     "lint": "oxlint .",
+    "fmt": "prettier --write .",
     "check:types": "tsc --noEmit",
     "build:types": "tsc --emitDeclarationOnly --declaration --declarationDir ./dist"
   },
   "devDependencies": {
     "bun-types": "canary",
-    "svelte": "^5.20.4"
+    "svelte": "^5.20.4",
+    "@threlte/core": "8.0.1"
   },
   "peerDependencies": {
-    "typescript": "^5",
     "svelte": "^5"
   },
   "files": [

packages/bun-plugin-svelte/src/index.ts

@@ -1,7 +1,13 @@
 import type { BunPlugin, BuildConfig, OnLoadResult } from "bun";
 import { basename } from "node:path";
 import { compile, compileModule } from "svelte/compiler";
-import { getBaseCompileOptions, validateOptions, type SvelteOptions, hash } from "./options";
+import {
+  getBaseCompileOptions,
+  validateOptions,
+  type SvelteOptions,
+  hash,
+  getBaseModuleCompileOptions,
+} from "./options";
 
 const kEmptyObject = Object.create(null);
 const virtualNamespace = "bun-svelte";
@@ -23,38 +29,52 @@ function SveltePlugin(options: SvelteOptions = kEmptyObject as SvelteOptions): B
   return {
     name: "bun-plugin-svelte",
     setup(builder) {
+      // resolve "svelte" export conditions
+      //
+      // FIXME: the dev server does not currently respect bundler configs; it
+      // just passes a fake one to plugins and then never uses it. we need to to
+      // update it to ~not~ do this.
+      if (builder?.config) {
+        var conditions = builder.config.conditions ?? [];
+        if (typeof conditions === "string") {
+          conditions = [conditions];
+        }
+        conditions.push("svelte");
+        builder.config.conditions = conditions;
+      }
+
       const { config = kEmptyObject as Partial<BuildConfig> } = builder;
       const baseCompileOptions = getBaseCompileOptions(options ?? (kEmptyObject as Partial<SvelteOptions>), config);
+      const baseModuleCompileOptions = getBaseModuleCompileOptions(
+        options ?? (kEmptyObject as Partial<SvelteOptions>),
+        config,
+      );
+
+      const ts = new Bun.Transpiler({
+        loader: "ts",
+        target: config.target,
+      });
 
       builder
-        .onLoad({ filter: /\.svelte(?:\.[tj]s)?$/ }, async args => {
+        .onLoad({ filter: /\.svelte$/ }, async function onLoadSvelte(args) {
           const { path } = args;
 
-          var isModule = false;
-
-          switch (path.substring(path.length - 2)) {
-            case "js":
-            case "ts":
-              isModule = true;
-              break;
-          }
-
           const sourceText = await Bun.file(path).text();
 
           const side =
             args && "side" in args // "side" only passed when run from dev server
               ? (args as { side: "client" | "server" }).side
               : "server";
-          const hmr = Boolean((args as { hmr?: boolean })["hmr"] ?? process.env.NODE_ENV !== "production");
           const generate = baseCompileOptions.generate ?? side;
 
-          const compileFn = isModule ? compileModule : compile;
-          const result = compileFn(sourceText, {
+          const hmr = Boolean((args as { hmr?: boolean })["hmr"] ?? process.env.NODE_ENV !== "production");
+          const result = compile(sourceText, {
             ...baseCompileOptions,
             generate,
             filename: args.path,
             hmr,
           });
+
           var { js, css } = result;
           if (css?.code && generate != "server") {
             const uid = `${basename(path)}-${hash(path)}-style`.replaceAll(`"`, `'`);
@@ -65,11 +85,37 @@ function SveltePlugin(options: SvelteOptions = kEmptyObject as SvelteOptions): B
 
           return {
             contents: result.js.code,
-            loader: "js",
+            loader: "ts",
           } satisfies OnLoadResult;
           // TODO: allow plugins to return multiple results.
           // TODO: support layered sourcemaps
         })
+        .onLoad({ filter: /\.svelte.[tj]s$/ }, async function onLoadSvelteModule(args) {
+          const { path } = args;
+
+          const side =
+            args && "side" in args // "side" only passed when run from dev server
+              ? (args as { side: "client" | "server" }).side
+              : "server";
+          const generate = baseModuleCompileOptions.generate ?? side;
+
+          var sourceText = await Bun.file(path).text();
+          if (path.endsWith(".ts")) {
+            sourceText = await ts.transform(sourceText);
+          }
+          const result = compileModule(sourceText, {
+            ...baseModuleCompileOptions,
+            generate,
+            filename: args.path,
+          });
+
+          // NOTE: we assume js/ts modules won't have CSS blocks in them, so no
+          // virtual modules get created.
+          return {
+            contents: result.js.code,
+            loader: "js",
+          };
+        })
         .onResolve({ filter: /^bun-svelte:/ }, args => {
           return {
             path: args.path,

packages/bun-plugin-svelte/src/options.ts

@@ -1,6 +1,6 @@
 import { strict as assert } from "node:assert";
-import type { BuildConfig } from "bun";
-import type { CompileOptions } from "svelte/compiler";
+import { type BuildConfig } from "bun";
+import type { CompileOptions, ModuleCompileOptions } from "svelte/compiler";
 
 export interface SvelteOptions {
   /**
@@ -44,8 +44,8 @@ export function validateOptions(options: unknown): asserts options is SvelteOpti
  * @internal
  */
 export function getBaseCompileOptions(pluginOptions: SvelteOptions, config: Partial<BuildConfig>): CompileOptions {
-  let { forceSide, development = false } = pluginOptions;
-  const { minify = false, target } = config;
+  let { development = false } = pluginOptions;
+  const { minify = false } = config;
 
   const shouldMinify = Boolean(minify);
   const {
@@ -60,6 +60,38 @@ export function getBaseCompileOptions(pluginOptions: SvelteOptions, config: Part
         identifiers: shouldMinify,
       };
 
+  const generate = generateSide(pluginOptions, config);
+
+  return {
+    css: "external",
+    generate,
+    preserveWhitespace: !minifyWhitespace,
+    preserveComments: !shouldMinify,
+    dev: development,
+    cssHash({ css }) {
+      // same prime number seed used by svelte/compiler.
+      // TODO: ensure this provides enough entropy
+      return `svelte-${hash(css)}`;
+    },
+  };
+}
+
+export function getBaseModuleCompileOptions(
+  pluginOptions: SvelteOptions,
+  config: Partial<BuildConfig>,
+): ModuleCompileOptions {
+  const { development = false } = pluginOptions;
+  const generate = generateSide(pluginOptions, config);
+  return {
+    dev: development,
+    generate,
+  };
+}
+
+function generateSide(pluginOptions: SvelteOptions, config: Partial<BuildConfig>) {
+  let { forceSide } = pluginOptions;
+  const { target } = config;
+
   if (forceSide == null && typeof target === "string") {
     switch (target) {
       case "browser":
@@ -73,19 +105,7 @@ export function getBaseCompileOptions(pluginOptions: SvelteOptions, config: Part
       // warn? throw?
     }
   }
-
-  return {
-    css: "external",
-    generate: forceSide,
-    preserveWhitespace: !minifyWhitespace,
-    preserveComments: !shouldMinify,
-    dev: development,
-    cssHash({ css }) {
-      // same prime number seed used by svelte/compiler.
-      // TODO: ensure this provides enough entropy
-      return `svelte-${hash(css)}`;
-    },
-  };
+  return forceSide;
 }
 
 export const hash = (content: string): string => Bun.hash(content, 5381).toString(36);

packages/bun-plugin-svelte/test/fixtures/svelte-export-condition.svelte

@@ -0,0 +1,17 @@
+<script>
+  import { Canvas } from "@threlte/core";
+  let name = "Bun";
+</script>
+
+<main class="app">
+  <h1>Cookin up apps with {name}</h1>
+  <Canvas />
+</main>
+
+<style>
+  h1 {
+    color: #ff3e00;
+    text-align: center;
+    font-size: 2em;
+  }
+</style>

packages/bun-plugin-svelte/test/fixtures/todo-cjs.svelte.ts

@@ -0,0 +1,15 @@
+class Todo {
+  title: string | undefined = $state();
+  done: boolean = $state(false);
+  createdAt: Date = $state(new Date());
+
+  constructor(title: string) {
+    this.title = title;
+  }
+
+  public toggle(): void {
+    this.done = !this.done;
+  }
+}
+
+module.exports = Todo;

packages/bun-plugin-svelte/test/fixtures/todo.svelte.ts

@@ -0,0 +1,13 @@
+export class Todo {
+  title: string | undefined = $state();
+  done: boolean = $state(false);
+  createdAt: Date = $state(new Date());
+
+  constructor(title: string) {
+    this.title = title;
+  }
+
+  public toggle(): void {
+    this.done = !this.done;
+  }
+}

packages/bun-plugin-svelte/test/fixtures/with-cjs.svelte

@@ -0,0 +1,25 @@
+<script lang="ts">
+  const Todo = require("./todo-cjs.svelte.ts");
+
+  let name = "World";
+  let todo: Todo = $state(new Todo("Hello World!"));
+</script>
+
+<main class="app">
+  <h1>Hello {todo.title}!</h1>
+  <!-- clicking calls toggle -->
+  <input type="checkbox" bind:checked={todo.done} />
+  <button onclick={todo.toggle}>Toggle</button>
+</main>
+
+<style>
+  h1 {
+    color: #ff3e00;
+    text-align: center;
+    font-size: 2em;
+    font-weight: 100;
+  }
+  .app {
+    box-sizing: border-box;
+  }
+</style>

packages/bun-plugin-svelte/test/fixtures/with-modules.svelte

@@ -0,0 +1,25 @@
+<script lang="ts">
+  import { Todo } from "./todo.svelte";
+
+  let name = "World";
+  let todo: Todo = $state(new Todo("Hello World!"));
+</script>
+
+<main class="app">
+  <h1>Hello {todo.title}!</h1>
+  <!-- clicking calls toggle -->
+  <input type="checkbox" bind:checked={todo.done} />
+  <button onclick={todo.toggle}>Toggle</button>
+</main>
+
+<style>
+  h1 {
+    color: #ff3e00;
+    text-align: center;
+    font-size: 2em;
+    font-weight: 100;
+  }
+  .app {
+    box-sizing: border-box;
+  }
+</style>

packages/bun-plugin-svelte/test/index.test.ts

@@ -4,6 +4,7 @@ import fs from "node:fs";
 import os from "node:os";
 import { render } from "svelte/server";
 import { SveltePlugin } from "../src";
+import type { BuildOutput } from "bun";
 
 const fixturePath = (...segs: string[]) => path.join(import.meta.dirname, "fixtures", ...segs);
 
@@ -32,6 +33,55 @@ it("hello world component", async () => {
   expect(res.success).toBeTrue();
 });
 
+describe("when importing `.svelte.ts` files with ESM", () => {
+  let res: BuildOutput;
+
+  beforeAll(async () => {
+    res = await Bun.build({
+      entrypoints: [fixturePath("with-modules.svelte")],
+      outdir,
+      plugins: [SveltePlugin()],
+    });
+  });
+
+  it("builds successfully", () => {
+    expect(res.success).toBeTrue();
+  });
+
+  it(`handles "svelte" export condition`, async () => {
+    const res = await Bun.build({
+      entrypoints: [fixturePath("svelte-export-condition.svelte")],
+      outdir,
+      plugins: [SveltePlugin()],
+    });
+    expect(res.success).toBeTrue();
+  });
+});
+
+describe("when importing `.svelte.ts` files with CJS", () => {
+  let res: BuildOutput;
+
+  beforeAll(async () => {
+    res = await Bun.build({
+      entrypoints: [fixturePath("with-cjs.svelte")],
+      outdir,
+      plugins: [SveltePlugin()],
+    });
+  });
+
+  it("builds successfully", () => {
+    expect(res.success).toBeTrue();
+  });
+
+  it("does not double-wrap the module with function(module, exports, __filename, __dirname)", async () => {
+    const ts = res.outputs.find(output => output.loader === "ts");
+    expect(ts).toBeDefined();
+    const code = await ts!.text();
+    expect(code).toContain("require_todo_cjs_svelte");
+    expect(code).toContain("var require_todo_cjs_svelte = __commonJS((exports, module) => {\n");
+  });
+});
+
 describe("Bun.build", () => {
   it.each(["node", "bun"] as const)('Generates server-side code when targeting "node" or "bun"', async target => {
     const res = await Bun.build({

packages/bun-types/bun.d.ts

@@ -1,74 +1,3 @@
-declare class _ShellError extends Error implements ShellOutput {
-  readonly stdout: Buffer;
-  readonly stderr: Buffer;
-  readonly exitCode: number;
-
-  /**
-   * Read from stdout as a string
-   *
-   * @param encoding - The encoding to use when decoding the output
-   * @returns Stdout as a string with the given encoding
-   * @example
-   *
-   * ## Read as UTF-8 string
-   *
-   * ```ts
-   * const output = await $`echo hello`;
-   * console.log(output.text()); // "hello\n"
-   * ```
-   *
-   * ## Read as base64 string
-   *
-   * ```ts
-   * const output = await $`echo ${atob("hello")}`;
-   * console.log(output.text("base64")); // "hello\n"
-   * ```
-   *
-   */
-  text(encoding?: BufferEncoding): string;
-
-  /**
-   * Read from stdout as a JSON object
-   *
-   * @returns Stdout as a JSON object
-   * @example
-   *
-   * ```ts
-   * const output = await $`echo '{"hello": 123}'`;
-   * console.log(output.json()); // { hello: 123 }
-   * ```
-   *
-   */
-  json(): any;
-
-  /**
-   * Read from stdout as an ArrayBuffer
-   *
-   * @returns Stdout as an ArrayBuffer
-   * @example
-   *
-   * ```ts
-   * const output = await $`echo hello`;
-   * console.log(output.arrayBuffer()); // ArrayBuffer { byteLength: 6 }
-   * ```
-   */
-  arrayBuffer(): ArrayBuffer;
-
-  /**
-   * Read from stdout as a Blob
-   *
-   * @returns Stdout as a blob
-   * @example
-   * ```ts
-   * const output = await $`echo hello`;
-   * console.log(output.blob()); // Blob { size: 6, type: "" }
-   * ```
-   */
-  blob(): Blob;
-
-  bytes(): Uint8Array;
-}
-
 /**
  * Bun.js runtime APIs
  *
@@ -185,6 +114,77 @@ declare module "bun" {
     | SpawnOptions.Writable
     | ReadableStream;
 
+  class ShellError extends Error implements ShellOutput {
+    readonly stdout: Buffer;
+    readonly stderr: Buffer;
+    readonly exitCode: number;
+
+    /**
+     * Read from stdout as a string
+     *
+     * @param encoding - The encoding to use when decoding the output
+     * @returns Stdout as a string with the given encoding
+     * @example
+     *
+     * ## Read as UTF-8 string
+     *
+     * ```ts
+     * const output = await $`echo hello`;
+     * console.log(output.text()); // "hello\n"
+     * ```
+     *
+     * ## Read as base64 string
+     *
+     * ```ts
+     * const output = await $`echo ${atob("hello")}`;
+     * console.log(output.text("base64")); // "hello\n"
+     * ```
+     *
+     */
+    text(encoding?: BufferEncoding): string;
+
+    /**
+     * Read from stdout as a JSON object
+     *
+     * @returns Stdout as a JSON object
+     * @example
+     *
+     * ```ts
+     * const output = await $`echo '{"hello": 123}'`;
+     * console.log(output.json()); // { hello: 123 }
+     * ```
+     *
+     */
+    json(): any;
+
+    /**
+     * Read from stdout as an ArrayBuffer
+     *
+     * @returns Stdout as an ArrayBuffer
+     * @example
+     *
+     * ```ts
+     * const output = await $`echo hello`;
+     * console.log(output.arrayBuffer()); // ArrayBuffer { byteLength: 6 }
+     * ```
+     */
+    arrayBuffer(): ArrayBuffer;
+
+    /**
+     * Read from stdout as a Blob
+     *
+     * @returns Stdout as a blob
+     * @example
+     * ```ts
+     * const output = await $`echo hello`;
+     * console.log(output.blob()); // Blob { size: 6, type: "" }
+     * ```
+     */
+    blob(): Blob;
+
+    bytes(): Uint8Array;
+  }
+
   class ShellPromise extends Promise<ShellOutput> {
     get stdin(): WritableStream;
     /**
@@ -304,12 +304,12 @@ declare module "bun" {
     new (): Shell;
   }
 
-  type ShellError = _ShellError;
-
   export interface Shell {
     (strings: TemplateStringsArray, ...expressions: ShellExpression[]): ShellPromise;
 
-    readonly ShellError: typeof _ShellError;
+    readonly Shell: ShellConstructor;
+    readonly ShellError: typeof ShellError;
+    readonly ShellPromise: typeof ShellPromise;
 
     /**
      * Perform bash-like brace expansion on the given pattern.
@@ -362,9 +362,6 @@ declare module "bun" {
      * Configure whether or not the shell should throw an exception on non-zero exit codes.
      */
     throws(shouldThrow: boolean): this;
-
-    readonly ShellPromise: typeof ShellPromise;
-    readonly Shell: ShellConstructor;
   }
 
   export interface ShellOutput {
@@ -2309,10 +2306,68 @@ declare module "bun" {
    */
   interface SavepointSQL extends SQL {}
 
+  type CSRFAlgorithm = "blake2b256" | "blake2b512" | "sha256" | "sha384" | "sha512" | "sha512-256";
+  interface CSRFGenerateOptions {
+    /**
+     * The number of milliseconds until the token expires. 0 means the token never expires.
+     * @default 24 * 60 * 60 * 1000 (24 hours)
+     */
+    expiresIn?: number;
+    /**
+     * The encoding of the token.
+     * @default "base64url"
+     */
+    encoding?: "base64" | "base64url" | "hex";
+    /**
+     * The algorithm to use for the token.
+     * @default "sha256"
+     */
+    algorithm?: CSRFAlgorithm;
+  }
+
+  interface CSRFVerifyOptions {
+    /**
+     * The secret to use for the token. If not provided, a random default secret will be generated in memory and used.
+     */
+    secret?: string;
+    /**
+     * The encoding of the token.
+     * @default "base64url"
+     */
+    encoding?: "base64" | "base64url" | "hex";
+    /**
+     * The algorithm to use for the token.
+     * @default "sha256"
+     */
+    algorithm?: CSRFAlgorithm;
+    /**
+     * The number of milliseconds until the token expires. 0 means the token never expires.
+     * @default 24 * 60 * 60 * 1000 (24 hours)
+     */
+    maxAge?: number;
+  }
+  interface CSRF {
+    /**
+     * Generate a CSRF token.
+     * @param secret The secret to use for the token. If not provided, a random default secret will be generated in memory and used.
+     * @param options The options for the token.
+     * @returns The generated token.
+     */
+    generate(secret?: string, options?: CSRFGenerateOptions): string;
+    /**
+     * Verify a CSRF token.
+     * @param token The token to verify.
+     * @param options The options for the token.
+     * @returns True if the token is valid, false otherwise.
+     */
+    verify(token: string, options?: CSRFVerifyOptions): boolean;
+  }
+
   var sql: SQL;
   var postgres: SQL;
   var SQL: SQL;
 
+  var CSRF: CSRF;
   /**
    *   This lets you use macros as regular imports
    *   @example
@@ -2657,7 +2712,7 @@ declare module "bun" {
     loader?: { [k in string]: Loader };
     /**
      * Specifies if and how to generate source maps.
-     * 
+     *
      * - `"none"` - No source maps are generated
      * - `"linked"` - A separate `*.ext.map` file is generated alongside each
      *   `*.ext` file. A `//# sourceMappingURL` comment is added to the output
@@ -2665,11 +2720,11 @@ declare module "bun" {
      * - `"inline"` - an inline source map is appended to the output file.
      * - `"external"` - Generate a separate source map file for each input file.
      *   No `//# sourceMappingURL` comment is added to the output file.
-     * 
+     *
      * `true` and `false` are aliasees for `"inline"` and `"none"`, respectively.
-     * 
+     *
      * @default "none"
-     * 
+     *
      * @see {@link outdir} required for `"linked"` maps
      * @see {@link publicPath} to customize the base url of linked source maps
      */
@@ -2704,10 +2759,10 @@ declare module "bun" {
     env?: "inline" | "disable" | `${string}*`;
     /**
      * Whether to enable minification.
-     * 
+     *
      * Use `true`/`false` to enable/disable all minification options. Alternatively,
      * you can pass an object for granular control over certain minifications.
-     * 
+     *
      * @default false
      */
     minify?:
@@ -3705,6 +3760,7 @@ declare module "bun" {
 
   interface BunRequest<T extends string = string> extends Request {
     params: RouterTypes.ExtractRouteParams<T>;
+    readonly cookies: CookieMap;
   }
 
   interface GenericServeOptions {
@@ -4265,17 +4321,7 @@ declare module "bun" {
      * Passing other options such as `port` or `hostname` won't do anything.
      */
     reload<T, R extends { [K in keyof R]: RouterTypes.RouteValue<K & string> }>(
-      options: (
-        | (Omit<ServeOptions, "fetch"> & {
-            routes: R;
-            fetch?: (this: Server, request: Request, server: Server) => Response | Promise<Response>;
-          })
-        | (Omit<ServeOptions, "routes"> & {
-            routes?: never;
-            fetch: (this: Server, request: Request, server: Server) => Response | Promise<Response>;
-          })
-        | WebSocketServeOptions<T>
-      ) & {
+      options: ServeFunctionOptions<T, R> & {
         /**
          * @deprecated Use `routes` instead in new code. This will continue to work for awhile though.
          */
@@ -4653,17 +4699,7 @@ declare module "bun" {
     @param options.routes - Route definitions mapping paths to handlers
     */
   function serve<T, R extends { [K in keyof R]: RouterTypes.RouteValue<K & string> }>(
-    options: (
-      | (DistributedOmit<Serve, "fetch"> & {
-          routes: R;
-          fetch?: (this: Server, request: Request, server: Server) => Response | Promise<Response>;
-        })
-      | (DistributedOmit<Serve, "routes"> & {
-          routes?: never;
-          fetch: (this: Server, request: Request, server: Server) => Response | Promise<Response>;
-        })
-      | WebSocketServeOptions<T>
-    ) & {
+    options: ServeFunctionOptions<T, R> & {
       /**
        * @deprecated Use `routes` instead in new code. This will continue to work for a while though.
        */
@@ -4671,6 +4707,32 @@ declare module "bun" {
     },
   ): Server;
 
+  type ServeFunctionOptions<T, R extends { [K in keyof R]: RouterTypes.RouteValue<K & string> }> =
+    | (DistributedOmit<Exclude<Serve<T>, WebSocketServeOptions<T>>, "fetch"> & {
+        routes: R;
+        fetch?: (this: Server, request: Request, server: Server) => Response | Promise<Response>;
+      })
+    | (DistributedOmit<Exclude<Serve<T>, WebSocketServeOptions<T>>, "routes"> & {
+        routes?: never;
+        fetch: (this: Server, request: Request, server: Server) => Response | Promise<Response>;
+      })
+    | (WebSocketServeOptions<T> & {
+        routes: R;
+        fetch?: (
+          this: Server,
+          request: Request,
+          server: Server,
+        ) => Response | Promise<Response | void | undefined> | void | undefined;
+      })
+    | (WebSocketServeOptions<T> & {
+        routes?: never;
+        fetch: (
+          this: Server,
+          request: Request,
+          server: Server,
+        ) => Response | Promise<Response | void | undefined> | void | undefined;
+      });
+
   /**
    * [`Blob`](https://developer.mozilla.org/en-US/docs/Web/API/Blob) powered by the fastest system calls available for operating on files.
    *
@@ -6239,7 +6301,7 @@ declare module "bun" {
      * @param socket
      */
     open?(socket: Socket<Data>): void | Promise<void>;
-    close?(socket: Socket<Data>): void | Promise<void>;
+    close?(socket: Socket<Data>, error?: Error): void | Promise<void>;
     error?(socket: Socket<Data>, error: Error): void | Promise<void>;
     data?(socket: Socket<Data>, data: BinaryTypeList[DataBinaryType]): void | Promise<void>;
     drain?(socket: Socket<Data>): void | Promise<void>;
@@ -6638,7 +6700,8 @@ declare module "bun" {
        * This is useful for aborting a subprocess when some other part of the
        * program is aborted, such as a `fetch` response.
        *
-       * Internally, this works by calling `subprocess.kill(1)`.
+       * If the signal is aborted, the process will be killed with the signal
+       * specified by `killSignal` (defaults to SIGTERM).
        *
        * @example
        * ```ts
@@ -6657,6 +6720,41 @@ declare module "bun" {
        * ```
        */
       signal?: AbortSignal;
+
+      /**
+       * The maximum amount of time the process is allowed to run in milliseconds.
+       *
+       * If the timeout is reached, the process will be killed with the signal
+       * specified by `killSignal` (defaults to SIGTERM).
+       *
+       * @example
+       * ```ts
+       * // Kill the process after 5 seconds
+       * const subprocess = Bun.spawn({
+       *   cmd: ["sleep", "10"],
+       *   timeout: 5000,
+       * });
+       * await subprocess.exited; // Will resolve after 5 seconds
+       * ```
+       */
+      timeout?: number;
+
+      /**
+       * The signal to use when killing the process after a timeout or when the AbortSignal is aborted.
+       *
+       * @default "SIGTERM" (signal 15)
+       *
+       * @example
+       * ```ts
+       * // Kill the process with SIGKILL after 5 seconds
+       * const subprocess = Bun.spawn({
+       *   cmd: ["sleep", "10"],
+       *   timeout: 5000,
+       *   killSignal: "SIGKILL",
+       * });
+       * ```
+       */
+      killSignal?: string | number;
     }
 
     type OptionsToSubprocess<Opts extends OptionsObject> =
@@ -6902,6 +7000,8 @@ declare module "bun" {
     resourceUsage: ResourceUsage;
 
     signalCode?: string;
+    exitedDueToTimeout?: true;
+    pid: number;
   }
 
   /**
@@ -7429,4 +7529,86 @@ declare module "bun" {
     | [pkg: string, info: BunLockFilePackageInfo, bunTag: string]
     /** root */
     | [pkg: string, info: Pick<BunLockFileBasePackageInfo, "bin" | "binDir">];
+
+  interface CookieInit {
+    name?: string;
+    value?: string;
+    domain?: string;
+    path?: string;
+    expires?: number | Date;
+    secure?: boolean;
+    sameSite?: CookieSameSite;
+    httpOnly?: boolean;
+    partitioned?: boolean;
+    maxAge?: number;
+  }
+
+  interface CookieStoreDeleteOptions {
+    name: string;
+    domain?: string | null;
+    path?: string;
+  }
+
+  interface CookieStoreGetOptions {
+    name?: string;
+    url?: string;
+  }
+
+  type CookieSameSite = "strict" | "lax" | "none";
+
+  class Cookie {
+    constructor(name: string, value: string, options?: CookieInit);
+    constructor(cookieString: string);
+    constructor(cookieObject?: CookieInit);
+
+    name: string;
+    value: string;
+    domain?: string;
+    path: string;
+    expires?: number;
+    secure: boolean;
+    sameSite: CookieSameSite;
+    partitioned: boolean;
+    maxAge?: number;
+    httpOnly: boolean;
+
+    isExpired(): boolean;
+
+    toString(): string;
+    toJSON(): CookieInit;
+
+    static parse(cookieString: string): Cookie;
+    static from(name: string, value: string, options?: CookieInit): Cookie;
+    static serialize(...cookies: Cookie[]): string;
+  }
+
+  class CookieMap implements Iterable<[string, Cookie]> {
+    constructor(init?: string[][] | Record<string, string> | string);
+
+    get(name: string): Cookie | null;
+    get(options?: CookieStoreGetOptions): Cookie | null;
+
+    getAll(name: string): Cookie[];
+    getAll(options?: CookieStoreGetOptions): Cookie[];
+
+    has(name: string, value?: string): boolean;
+
+    set(name: string, value: string): void;
+    set(options: CookieInit): void;
+
+    delete(name: string): void;
+    delete(options: CookieStoreDeleteOptions): void;
+
+    toString(): string;
+
+    toJSON(): Record<string, ReturnType<Cookie["toJSON"]>>;
+    readonly size: number;
+
+    entries(): IterableIterator<[string, Cookie]>;
+    keys(): IterableIterator<string>;
+    values(): IterableIterator<Cookie>;
+    forEach(callback: (value: Cookie, key: string, map: CookieMap) => void, thisArg?: any): void;
+
+    [Symbol.iterator](): IterableIterator<[string, Cookie]>;
+  }
 }

packages/bun-types/devserver.d.ts

@@ -1,6 +1,24 @@
 export {};
 
 declare global {
+  namespace Bun {
+    type HMREventNames =
+      | "bun:ready"
+      | "bun:beforeUpdate"
+      | "bun:afterUpdate"
+      | "bun:beforeFullReload"
+      | "bun:beforePrune"
+      | "bun:invalidate"
+      | "bun:error"
+      | "bun:ws:disconnect"
+      | "bun:ws:connect";
+
+    /**
+     * The event names for the dev server
+     */
+    type HMREvent = `bun:${HMREventNames}` | (string & {});
+  }
+
   interface ImportMeta {
     /**
      * Hot module replacement APIs. This value is `undefined` in production and
@@ -32,8 +50,6 @@ declare global {
        *
        * In production, `data` is inlined to be `{}`. This is handy because Bun
        * knows it can minify `{}.prop ??= value` into `value` in production.
-       *
-       *
        */
       data: any;
 
@@ -128,6 +144,49 @@ declare global {
        * @deprecated
        */
       decline(): void;
+
+      // NOTE TO CONTRIBUTORS ////////////////////////////////////////
+      //     Callback is currently never called for `.prune()`      //
+      //     so the types are commented out until we support it.    //
+      ////////////////////////////////////////////////////////////////
+      // /**
+      //  * Attach a callback that is called when the module is removed from the module graph.
+      //  *
+      //  * This can be used to clean up resources that were created when the module was loaded.
+      //  * Unlike `import.meta.hot.dispose()`, this pairs much better with `accept` and `data` to manage stateful resources.
+      //  *
+      //  * @example
+      //  * ```ts
+      //  * export const ws = (import.meta.hot.data.ws ??= new WebSocket(location.origin));
+      //  *
+      //  * import.meta.hot.prune(() => {
+      //  *   ws.close();
+      //  * });
+      //  * ```
+      //  */
+      // prune(callback: () => void): void;
+
+      /**
+       * Listen for an event from the dev server
+       *
+       * For compatibility with Vite, event names are also available via vite:* prefix instead of bun:*.
+       *
+       * https://bun.sh/docs/bundler/hmr#import-meta-hot-on-and-off
+       * @param event The event to listen to
+       * @param callback The callback to call when the event is emitted
+       */
+      on(event: Bun.HMREvent, callback: () => void): void;
+
+      /**
+       * Stop listening for an event from the dev server
+       *
+       * For compatibility with Vite, event names are also available via vite:* prefix instead of bun:*.
+       *
+       * https://bun.sh/docs/bundler/hmr#import-meta-hot-on-and-off
+       * @param event The event to stop listening to
+       * @param callback The callback to stop listening to
+       */
+      off(event: Bun.HMREvent, callback: () => void): void;
     };
   }
 }

packages/bun-types/globals.d.ts

@@ -76,6 +76,17 @@ declare global {
       revision: string;
       reallyExit(code?: number): never;
       dlopen(module: { exports: any }, filename: string, flags?: number): void;
+      _exiting: boolean;
+      noDeprecation: boolean;
+
+      binding(m: string): object;
+      binding(m: "constants"): {
+        os: typeof import("node:os").constants;
+        fs: typeof import("node:fs").constants;
+        crypto: typeof import("node:crypto").constants;
+        zlib: typeof import("node:zlib").constants;
+        trace: typeof import("node:trace").constants;
+      };
     }
   }
 
@@ -1765,6 +1776,71 @@ declare global {
      */
     bytes(): Promise<Uint8Array>;
   }
-
   var Blob: typeof Blob;
+
+  interface Uint8Array {
+    /**
+     * Convert the Uint8Array to a base64 encoded string
+     * @returns The base64 encoded string representation of the Uint8Array
+     */
+    toBase64(options?: { alphabet?: "base64" | "base64url"; omitPadding?: boolean }): string;
+
+    /**
+     * Set the contents of the Uint8Array from a base64 encoded string
+     * @param base64 The base64 encoded string to decode into the array
+     * @param offset Optional starting index to begin setting the decoded bytes (default: 0)
+     */
+    setFromBase64(
+      base64: string,
+      offset?: number,
+    ): {
+      /**
+       * The number of bytes read from the base64 string
+       */
+      read: number;
+      /**
+       * The number of bytes written to the Uint8Array
+       * Will never be greater than the `.byteLength` of this Uint8Array
+       */
+      written: number;
+    };
+
+    /**
+     * Convert the Uint8Array to a hex encoded string
+     * @returns The hex encoded string representation of the Uint8Array
+     */
+    toHex(): string;
+
+    /**
+     * Set the contents of the Uint8Array from a hex encoded string
+     * @param hex The hex encoded string to decode into the array. The string must have
+     * an even number of characters, be valid hexadecimal characters and contain no whitespace.
+     */
+    setFromHex(hex: string): {
+      /**
+       * The number of bytes read from the hex string
+       */
+      read: number;
+      /**
+       * The number of bytes written to the Uint8Array
+       * Will never be greater than the `.byteLength` of this Uint8Array
+       */
+      written: number;
+    };
+  }
+
+  interface Uint8ArrayConstructor {
+    /**
+     * Create a new Uint8Array from a base64 encoded string
+     * @param base64 The base64 encoded string to convert to a Uint8Array
+     * @returns A new Uint8Array containing the decoded data
+     */
+    fromBase64(
+      base64: string,
+      options?: {
+        alphabet?: "base64" | "base64url";
+        lastChunkHandling?: "loose" | "strict" | "stop-before-partial";
+      },
+    ): Uint8Array;
+  }
 }

packages/bun-types/sqlite.d.ts

@@ -477,6 +477,79 @@ declare module "bun:sqlite" {
      */
     static deserialize(serialized: NodeJS.TypedArray | ArrayBufferLike, isReadOnly?: boolean): Database;
 
+    /**
+     * Load a serialized SQLite3 database. This version enables you to specify
+     * additional options such as `strict` to put the database into strict mode.
+     *
+     * Internally, this calls `sqlite3_deserialize`.
+     *
+     * @param serialized Data to load
+     * @returns `Database` instance
+     *
+     * @example
+     * ```ts
+     * test("supports serialize/deserialize", () => {
+     *     const db = Database.open(":memory:");
+     *     db.exec("CREATE TABLE test (id INTEGER PRIMARY KEY, name TEXT)");
+     *     db.exec('INSERT INTO test (name) VALUES ("Hello")');
+     *     db.exec('INSERT INTO test (name) VALUES ("World")');
+     *
+     *     const input = db.serialize();
+     *     const db2 = Database.deserialize(input, { strict: true });
+     *
+     *     const stmt = db2.prepare("SELECT * FROM test");
+     *     expect(JSON.stringify(stmt.get())).toBe(
+     *       JSON.stringify({
+     *         id: 1,
+     *         name: "Hello",
+     *       }),
+     *     );
+     *
+     *     expect(JSON.stringify(stmt.all())).toBe(
+     *       JSON.stringify([
+     *         {
+     *           id: 1,
+     *           name: "Hello",
+     *         },
+     *         {
+     *           id: 2,
+     *           name: "World",
+     *         },
+     *       ]),
+     *     );
+     *     db2.exec("insert into test (name) values ($foo)", { foo: "baz" });
+     *     expect(JSON.stringify(stmt.all())).toBe(
+     *       JSON.stringify([
+     *         {
+     *           id: 1,
+     *           name: "Hello",
+     *         },
+     *         {
+     *           id: 2,
+     *           name: "World",
+     *         },
+     *         {
+     *           id: 3,
+     *           name: "baz",
+     *         },
+     *       ]),
+     *     );
+     *
+     *     const db3 = Database.deserialize(input, { readonly: true, strict: true });
+     *     try {
+     *       db3.exec("insert into test (name) values ($foo)", { foo: "baz" });
+     *       throw new Error("Expected error");
+     *     } catch (e) {
+     *       expect(e.message).toBe("attempt to write a readonly database");
+     *     }
+     * });
+     * ```
+     */
+    static deserialize(
+      serialized: NodeJS.TypedArray | ArrayBufferLike,
+      options?: { readonly?: boolean; strict?: boolean; safeIntegers?: boolean },
+    ): Database;
+
     /**
      * See `sqlite3_file_control` for more information.
      * @link https://www.sqlite.org/c3ref/file_control.html

packages/bun-usockets/src/context.c

@@ -72,7 +72,7 @@ void us_socket_context_close(int ssl, struct us_socket_context_t *context) {
     while (ls) {
         struct us_listen_socket_t *nextLS = (struct us_listen_socket_t *) ls->s.next;
         us_listen_socket_close(ssl, ls);
-        
+
         ls = nextLS;
     }
 
@@ -310,7 +310,7 @@ struct us_bun_verify_error_t us_socket_verify_error(int ssl, struct us_socket_t
         }
     #endif
 
-    return (struct us_bun_verify_error_t) { .error = 0, .code = NULL, .reason = NULL };    
+    return (struct us_bun_verify_error_t) { .error = 0, .code = NULL, .reason = NULL };
 }
 
 void us_internal_socket_context_free(int ssl, struct us_socket_context_t *context) {
@@ -337,7 +337,7 @@ void us_socket_context_ref(int ssl, struct us_socket_context_t *context) {
 }
 void us_socket_context_unref(int ssl, struct us_socket_context_t *context) {
     uint32_t ref_count = context->ref_count;
-    context->ref_count--;    
+    context->ref_count--;
     if (ref_count == 1) {
         us_internal_socket_context_free(ssl, context);
     }
@@ -520,7 +520,7 @@ void *us_socket_context_connect(int ssl, struct us_socket_context_t *context, co
     }
 
     struct us_connecting_socket_t *c = us_calloc(1, sizeof(struct us_connecting_socket_t) + socket_ext_size);
-    c->socket_ext_size = socket_ext_size;  
+    c->socket_ext_size = socket_ext_size;
     c->options = options;
     c->ssl = ssl > 0;
     c->timeout = 255;
@@ -641,9 +641,9 @@ void us_internal_socket_after_open(struct us_socket_t *s, int error) {
 
         /* Emit error, close without emitting on_close */
 
-        /* There are two possible states here: 
-            1. It's a us_connecting_socket_t*. DNS resolution failed, or a connection failed. 
-            2. It's a us_socket_t* 
+        /* There are two possible states here:
+            1. It's a us_connecting_socket_t*. DNS resolution failed, or a connection failed.
+            2. It's a us_socket_t*
 
             We differentiate between these two cases by checking if the connect_state is null.
         */
@@ -887,7 +887,7 @@ void us_socket_context_on_connect_error(int ssl, struct us_socket_context_t *con
         return;
     }
 #endif
-    
+
     context->on_connect_error = on_connect_error;
 }
 
@@ -898,7 +898,7 @@ void us_socket_context_on_socket_connect_error(int ssl, struct us_socket_context
         return;
     }
 #endif
-    
+
     context->on_socket_connect_error = on_connect_error;
 }
 

packages/bun-usockets/src/eventing/epoll_kqueue.c

@@ -270,7 +270,6 @@ void us_loop_run_bun_tick(struct us_loop_t *loop, const struct timespec* timeout
 
     /* Fetch ready polls */
 #ifdef LIBUS_USE_EPOLL
-    
     loop->num_ready_polls = bun_epoll_pwait2(loop->fd, loop->ready_polls, 1024, timeout);
 #else
     do {

packages/bun-usockets/src/socket.c

@@ -22,7 +22,6 @@
 #include <string.h>
 #include <stdint.h>
 #include <errno.h>
-
 #ifndef WIN32
 #include <fcntl.h>
 #endif
@@ -168,13 +167,17 @@ void us_connecting_socket_close(int ssl, struct us_connecting_socket_t *c) {
     if (!c->pending_resolve_callback) {
         us_connecting_socket_free(ssl, c);
     }
-} 
+}
 
 struct us_socket_t *us_socket_close(int ssl, struct us_socket_t *s, int code, void *reason) {
     if(ssl) {
         return (struct us_socket_t *)us_internal_ssl_socket_close((struct us_internal_ssl_socket_t *) s, code, reason);
     }
+
     if (!us_socket_is_closed(0, s)) {
+        /* make sure the context is alive until the callback ends */
+        us_socket_context_ref(ssl, s->context);
+
         if (s->low_prio_state == 1) {
             /* Unlink this socket from the low-priority queue */
             if (!s->prev) s->context->loop->data.low_prio_head = s->next;
@@ -186,7 +189,6 @@ struct us_socket_t *us_socket_close(int ssl, struct us_socket_t *s, int code, vo
             s->next = 0;
             s->low_prio_state = 0;
             us_socket_context_unref(ssl, s->context);
-
         } else {
             us_internal_socket_context_unlink_socket(ssl, s->context, s);
         }
@@ -207,18 +209,27 @@ struct us_socket_t *us_socket_close(int ssl, struct us_socket_t *s, int code, vo
 
         bsd_close_socket(us_poll_fd((struct us_poll_t *) s));
 
-        /* Link this socket to the close-list and let it be deleted after this iteration */
-        s->next = s->context->loop->data.closed_head;
-        s->context->loop->data.closed_head = s;
 
         /* Any socket with prev = context is marked as closed */
         s->prev = (struct us_socket_t *) s->context;
 
+        /* mark it as closed and call the callback */
+        struct us_socket_t *res = s;
         if (!(us_internal_poll_type(&s->p) & POLL_TYPE_SEMI_SOCKET)) {
-            return s->context->on_close(s, code, reason);
+            res = s->context->on_close(s, code, reason);
         }
-        
+
+        /* Link this socket to the close-list and let it be deleted after this iteration */
+        s->next = s->context->loop->data.closed_head;
+        s->context->loop->data.closed_head = s;
+
+        /* unref the context after the callback ends */
+        us_socket_context_unref(ssl, s->context);
+
+        /* preserve the return value from on_close if its called */
+        return res;
     }
+
     return s;
 }
 
@@ -435,18 +446,18 @@ int us_connecting_socket_get_error(int ssl, struct us_connecting_socket_t *c) {
     return c->error;
 }
 
-/* 
+/*
     Note: this assumes that the socket is non-TLS and will be adopted and wrapped with a new TLS context
           context ext will not be copied to the new context, new context will contain us_wrapped_socket_context_t on ext
 */
 struct us_socket_t *us_socket_wrap_with_tls(int ssl, struct us_socket_t *s, struct us_bun_socket_context_options_t options, struct us_socket_events_t events, int socket_ext_size) {
     // only accepts non-TLS sockets
     if (ssl) {
-        return NULL; 
+        return NULL;
     }
 
     return(struct us_socket_t *) us_internal_ssl_socket_wrap_with_tls(s, options, events, socket_ext_size);
-}  
+}
 
 // if a TLS socket calls this, it will start SSL call open event and TLS handshake if required
 // will have no effect if the socket is closed or is not TLS
@@ -503,9 +514,14 @@ void us_socket_nodelay(struct us_socket_t *s, int enabled) {
     }
 }
 
+/// Returns 0 on success. Returned error values depend on the platform.
+/// - on posix, returns `errno`
+/// - on windows, when libuv is used, returns a UV err code
+/// - on windows, LIBUS_USE_LIBUV is set, returns `WSAGetLastError()`
+/// - on windows, otherwise returns result of `WSAGetLastError`
 int us_socket_keepalive(us_socket_r s, int enabled, unsigned int delay){
     if (!us_socket_is_shut_down(0, s)) {
-        bsd_socket_keepalive(us_poll_fd((struct us_poll_t *) s), enabled, delay);
+        return bsd_socket_keepalive(us_poll_fd((struct us_poll_t *) s), enabled, delay);
     }
     return 0;
 }
@@ -544,4 +560,4 @@ void us_socket_resume(int ssl, struct us_socket_t *s) {
     }
     // we are readable and writable so we resume everything
     us_poll_change(&s->p, s->context->loop, LIBUS_SOCKET_READABLE | LIBUS_SOCKET_WRITABLE);
-  }
+  }

packages/bun-uws/src/App.h

@@ -189,6 +189,10 @@ public:
      * This function should probably be optimized a lot in future releases,
      * it could be O(1) with a hash map of fullnames and their counts. */
     unsigned int numSubscribers(std::string_view topic) {
+        if (!topicTree) {
+            return 0;
+        }
+
         Topic *t = topicTree->lookupTopic(topic);
         if (t) {
             return (unsigned int) t->size();
@@ -408,14 +412,14 @@ public:
         webSocketContext->getExt()->messageHandler = std::move(behavior.message);
         webSocketContext->getExt()->drainHandler = std::move(behavior.drain);
         webSocketContext->getExt()->subscriptionHandler = std::move(behavior.subscription);
-        webSocketContext->getExt()->closeHandler = std::move([closeHandler = std::move(behavior.close)](WebSocket<SSL, true, UserData> *ws, int code, std::string_view message) mutable {
+        webSocketContext->getExt()->closeHandler = [closeHandler = std::move(behavior.close)](WebSocket<SSL, true, UserData> *ws, int code, std::string_view message) mutable {
             if (closeHandler) {
                 closeHandler(ws, code, message);
             }
 
             /* Destruct user data after returning from close handler */
             ((UserData *) ws->getUserData())->~UserData();
-        });
+        };
         webSocketContext->getExt()->pingHandler = std::move(behavior.ping);
         webSocketContext->getExt()->pongHandler = std::move(behavior.pong);
 
@@ -428,8 +432,8 @@ public:
         webSocketContext->getExt()->maxLifetime = behavior.maxLifetime;
         webSocketContext->getExt()->compression = behavior.compression;
 
-        /* Calculate idleTimeoutCompnents */
-        webSocketContext->getExt()->calculateIdleTimeoutCompnents(behavior.idleTimeout);
+        /* Calculate idleTimeoutComponents */
+        webSocketContext->getExt()->calculateIdleTimeoutComponents(behavior.idleTimeout);
 
         httpContext->onHttp("GET", pattern, [webSocketContext, behavior = std::move(behavior)](auto *res, auto *req) mutable {
 
@@ -606,11 +610,20 @@ public:
         return std::move(*this);
     }
 
+    void setOnClose(HttpContextData<SSL>::OnSocketClosedCallback onClose) {
+        httpContext->getSocketContextData()->onSocketClosed = onClose;
+    }
+
     TemplatedApp &&run() {
         uWS::run();
         return std::move(*this);
     }
 
+    TemplatedApp &&setUsingCustomExpectHandler(bool value) {
+        httpContext->getSocketContextData()->usingCustomExpectHandler = value;
+        return std::move(*this);
+    }
+
 };
 
 typedef TemplatedApp<false> App;

packages/bun-uws/src/AsyncSocket.h

@@ -30,6 +30,9 @@
 #include <iostream>
 
 #include "libusockets.h"
+#include "bun-usockets/src/internal/internal.h"
+
+
 
 #include "LoopData.h"
 #include "AsyncSocketData.h"
@@ -54,28 +57,6 @@ struct AsyncSocket {
     template <typename, typename> friend struct TopicTree;
     template <bool> friend struct HttpResponse;
 
-private:
-    /* Helper, do not use directly (todo: move to uSockets or de-crazify) */
-    void throttle_helper(int toggle) {
-        /* These should be exposed by uSockets */
-        static thread_local int us_events[2] = {0, 0};
-
-        struct us_poll_t *p = (struct us_poll_t *) this;
-        struct us_loop_t *loop = us_socket_context_loop(SSL, us_socket_context(SSL, (us_socket_t *) this));
-
-        if (toggle) {
-            /* Pause */
-            int events = us_poll_events(p);
-            if (events) {
-                us_events[getBufferedAmount() ? 1 : 0] = events;
-            }
-            us_poll_change(p, loop, 0);
-        } else {
-            /* Resume */
-            int events = us_events[getBufferedAmount() ? 1 : 0];
-            us_poll_change(p, loop, events);
-        }
-    }
 
 public:
     /* Returns SSL pointer or FD as pointer */
@@ -105,13 +86,13 @@ public:
 
     /* Experimental pause */
     us_socket_t *pause() {
-        throttle_helper(1);
+        us_socket_pause(SSL, (us_socket_t *) this);
         return (us_socket_t *) this;
     }
 
     /* Experimental resume */
     us_socket_t *resume() {
-        throttle_helper(0);
+        us_socket_resume(SSL, (us_socket_t *) this);
         return (us_socket_t *) this;
     }
 

packages/bun-uws/src/AsyncSocketData.h

@@ -81,7 +81,7 @@ struct AsyncSocketData {
 
     }
 
-    /* Or emppty */
+    /* Or empty */
     AsyncSocketData() = default;
 };
 

packages/bun-uws/src/HttpContext.h

@@ -43,10 +43,10 @@ private:
     HttpContext() = delete;
 
     /* Maximum delay allowed until an HTTP connection is terminated due to outstanding request or rejected data (slow loris protection) */
-    static const int HTTP_IDLE_TIMEOUT_S = 10;
+    static constexpr int HTTP_IDLE_TIMEOUT_S = 10;
 
     /* Minimum allowed receive throughput per second (clients uploading less than 16kB/sec get dropped) */
-    static const int HTTP_RECEIVE_THROUGHPUT_BYTES = 16 * 1024;
+    static constexpr int HTTP_RECEIVE_THROUGHPUT_BYTES = 16 * 1024;
 
     us_socket_context_t *getSocketContext() {
         return (us_socket_context_t *) this;
@@ -115,9 +115,8 @@ private:
         us_socket_context_on_close(SSL, getSocketContext(), [](us_socket_t *s, int /*code*/, void */*reason*/) {
             ((AsyncSocket<SSL> *)s)->uncorkWithoutSending();
 
-
             /* Get socket ext */
-            HttpResponseData<SSL> *httpResponseData = (HttpResponseData<SSL> *) us_socket_ext(SSL, s);
+            auto *httpResponseData = reinterpret_cast<HttpResponseData<SSL> *>(us_socket_ext(SSL, s));
 
             /* Call filter */
             HttpContextData<SSL> *httpContextData = getSocketContextDataS(s);
@@ -130,6 +129,9 @@ private:
                 httpResponseData->onAborted((HttpResponse<SSL> *)s, httpResponseData->userData);
             }
 
+            if (httpResponseData->socketData && httpContextData->onSocketClosed) {
+                httpContextData->onSocketClosed(httpResponseData->socketData, SSL, s);
+            }
 
             /* Destruct socket ext */
             httpResponseData->~HttpResponseData<SSL>();
@@ -171,7 +173,7 @@ private:
             proxyParser = &httpResponseData->proxyParser;
 #endif
 
-            /* The return value is entirely up to us to interpret. The HttpParser only care for whether the returned value is DIFFERENT or not from passed user */
+            /* The return value is entirely up to us to interpret. The HttpParser cares only for whether the returned value is DIFFERENT from passed user */
             auto [err, returnedSocket] = httpResponseData->consumePostPadded(data, (unsigned int) length, s, proxyParser, [httpContextData](void *s, HttpRequest *httpRequest) -> void * {
                 /* For every request we reset the timeout and hang until user makes action */
                 /* Warning: if we are in shutdown state, resetting the timer is a security issue! */
@@ -182,7 +184,7 @@ private:
                 httpResponseData->offset = 0;
 
                 /* Are we not ready for another request yet? Terminate the connection.
-                 * Important for denying async pipelining until, if ever, we want to suppot it.
+                 * Important for denying async pipelining until, if ever, we want to support it.
                  * Otherwise requests can get mixed up on the same connection. We still support sync pipelining. */
                 if (httpResponseData->state & HttpResponseData<SSL>::HTTP_RESPONSE_PENDING) {
                     us_socket_close(SSL, (us_socket_t *) s, 0, nullptr);
@@ -197,6 +199,8 @@ private:
                     httpResponseData->state |= HttpResponseData<SSL>::HTTP_CONNECTION_CLOSE;
                 }
 
+                httpResponseData->fromAncientRequest = httpRequest->isAncient();
+
                 /* Select the router based on SNI (only possible for SSL) */
                 auto *selectedRouter = &httpContextData->router;
                 if constexpr (SSL) {
@@ -358,9 +362,8 @@ private:
 
         /* Handle HTTP write out (note: SSL_read may trigger this spuriously, the app need to handle spurious calls) */
         us_socket_context_on_writable(SSL, getSocketContext(), [](us_socket_t *s) {
-
-            AsyncSocket<SSL> *asyncSocket = (AsyncSocket<SSL> *) s;
-            HttpResponseData<SSL> *httpResponseData = (HttpResponseData<SSL> *) asyncSocket->getAsyncSocketData();
+            auto *asyncSocket = reinterpret_cast<AsyncSocket<SSL> *>(s);
+            auto *httpResponseData = reinterpret_cast<HttpResponseData<SSL> *>(asyncSocket->getAsyncSocketData());
 
             /* Ask the developer to write data and return success (true) or failure (false), OR skip sending anything and return success (true). */
             if (httpResponseData->onWritable) {
@@ -369,7 +372,7 @@ private:
 
                 /* We expect the developer to return whether or not write was successful (true).
                  * If write was never called, the developer should still return true so that we may drain. */
-                bool success = httpResponseData->callOnWritable((HttpResponse<SSL> *)asyncSocket, httpResponseData->offset);
+                bool success = httpResponseData->callOnWritable(reinterpret_cast<HttpResponse<SSL> *>(asyncSocket), httpResponseData->offset);
 
                 /* The developer indicated that their onWritable failed. */
                 if (!success) {
@@ -396,28 +399,26 @@ private:
             }
 
             /* Expect another writable event, or another request within the timeout */
-            ((HttpResponse<SSL> *) s)->resetTimeout();
+            reinterpret_cast<HttpResponse<SSL> *>(s)->resetTimeout();
 
             return s;
         });
 
         /* Handle FIN, HTTP does not support half-closed sockets, so simply close */
         us_socket_context_on_end(SSL, getSocketContext(), [](us_socket_t *s) {
-            ((AsyncSocket<SSL> *)s)->uncorkWithoutSending();
-
+            auto *asyncSocket = reinterpret_cast<AsyncSocket<SSL> *>(s);
+            asyncSocket->uncorkWithoutSending();
             /* We do not care for half closed sockets */
-            AsyncSocket<SSL> *asyncSocket = (AsyncSocket<SSL> *) s;
             return asyncSocket->close();
-
         });
 
         /* Handle socket timeouts, simply close them so to not confuse client with FIN */
         us_socket_context_on_timeout(SSL, getSocketContext(), [](us_socket_t *s) {
 
             /* Force close rather than gracefully shutdown and risk confusing the client with a complete download */
-            AsyncSocket<SSL> *asyncSocket = (AsyncSocket<SSL> *) s;
-            // Node.js by default sclose the connection but they emit the timeout event before that
-            HttpResponseData<SSL> *httpResponseData = (HttpResponseData<SSL> *) asyncSocket->getAsyncSocketData();
+            AsyncSocket<SSL> *asyncSocket = reinterpret_cast<AsyncSocket<SSL> *>(s);
+            // Node.js by default closes the connection but they emit the timeout event before that
+            HttpResponseData<SSL> *httpResponseData = reinterpret_cast<HttpResponseData<SSL> *>(asyncSocket->getAsyncSocketData());
 
             if (httpResponseData->onTimeout) {
                 httpResponseData->onTimeout((HttpResponse<SSL> *)s, httpResponseData->userData);
@@ -493,16 +494,20 @@ public:
             }
         }
 
-        httpContextData->currentRouter->add(methods, pattern, [handler = std::move(handler), parameterOffsets = std::move(parameterOffsets)](auto *r) mutable {
+        const bool &customContinue = httpContextData->usingCustomExpectHandler;
+
+        httpContextData->currentRouter->add(methods, pattern, [handler = std::move(handler), parameterOffsets = std::move(parameterOffsets), &customContinue](auto *r) mutable {
             auto user = r->getUserData();
             user.httpRequest->setYield(false);
             user.httpRequest->setParameters(r->getParameters());
             user.httpRequest->setParameterOffsets(&parameterOffsets);
 
-            /* Middleware? Automatically respond to expectations */
-            std::string_view expect = user.httpRequest->getHeader("expect");
-            if (expect.length() && expect == "100-continue") {
-                user.httpResponse->writeContinue();
+            if (!customContinue) {
+                /* Middleware? Automatically respond to expectations */
+                std::string_view expect = user.httpRequest->getHeader("expect");
+                if (expect.length() && expect == "100-continue") {
+                    user.httpResponse->writeContinue();
+                }
             }
 
             handler(user.httpResponse, user.httpRequest);

packages/bun-uws/src/HttpContextData.h

@@ -34,6 +34,7 @@ struct alignas(16) HttpContextData {
     template <bool> friend struct TemplatedApp;
 private:
     std::vector<MoveOnlyFunction<void(HttpResponse<SSL> *, int)>> filterHandlers;
+    using OnSocketClosedCallback = void (*)(void* userData, int is_ssl, struct us_socket_t *rawSocket);
 
     MoveOnlyFunction<void(const char *hostname)> missingServerNameHandler;
 
@@ -50,6 +51,10 @@ private:
     void *upgradedWebSocket = nullptr;
     bool isParsingHttp = false;
     bool rejectUnauthorized = false;
+    bool usingCustomExpectHandler = false;
+
+    /* Used to simulate Node.js socket events. */
+    OnSocketClosedCallback onSocketClosed = nullptr;
 
     // TODO: SNI
     void clearRoutes() {

packages/bun-uws/src/HttpParser.h

@@ -239,7 +239,7 @@ namespace uWS
             }
             return unsignedIntegerValue;
         }
-        
+
         static inline uint64_t hasLess(uint64_t x, uint64_t n) {
             return (((x)-~0ULL/255*(n))&~(x)&~0ULL/255*128);
         }
@@ -283,7 +283,7 @@ namespace uWS
             }
             return false;
         }
-        
+
         static inline void *consumeFieldName(char *p) {
             /* Best case fast path (particularly useful with clang) */
             while (true) {
@@ -323,14 +323,14 @@ namespace uWS
 
             uint64_t http;
             __builtin_memcpy(&http, data, sizeof(uint64_t));
-            
+
             uint32_t first_four_bytes = http & static_cast<uint32_t>(0xFFFFFFFF);
             // check if any of the first four bytes are > non-ascii
             if ((first_four_bytes & 0x80808080) != 0) [[unlikely]] {
                 return 0;
             }
             first_four_bytes |= 0x20202020; // Lowercase the first four bytes
-            
+
             static constexpr char http_lowercase_bytes[4] = {'h', 't', 't', 'p'};
             static constexpr uint32_t http_lowercase_bytes_int = __builtin_bit_cast(uint32_t, http_lowercase_bytes);
             if (first_four_bytes == http_lowercase_bytes_int) [[likely]] {
@@ -343,7 +343,7 @@ namespace uWS
 
                 static constexpr char S_colon_slash_slash[4] = {'S', ':', '/', '/'};
                 static constexpr uint32_t S_colon_slash_slash_int = __builtin_bit_cast(uint32_t, S_colon_slash_slash);
-              
+
                 // Extract the last four bytes from the uint64_t
                 const uint32_t last_four_bytes = (http >> 32) & static_cast<uint32_t>(0xFFFFFFFF);
                 return (last_four_bytes == s_colon_slash_slash_int) || (last_four_bytes == S_colon_slash_slash_int);
@@ -361,7 +361,7 @@ namespace uWS
             if (&data[1] == end) [[unlikely]] {
                 return nullptr;
             }
-            
+
             if (data[0] == 32 && (__builtin_expect(data[1] == '/', 1) || isHTTPorHTTPSPrefixForProxies(data + 1, end) == 1)) [[likely]] {
                 header.key = {start, (size_t) (data - start)};
                 data++;
@@ -536,7 +536,7 @@ namespace uWS
                     while (headers->value.length() && headers->value.front() < 33) {
                         headers->value.remove_prefix(1);
                     }
-                    
+
                     headers++;
 
                     /* We definitely have at least one header (or request line), so check if we are done */
@@ -598,7 +598,7 @@ namespace uWS
             for (HttpRequest::Header *h = req->headers; (++h)->key.length(); ) {
                 req->bf.add(h->key);
             }
-            
+
             /* Break if no host header (but we can have empty string which is different from nullptr) */
             if (!req->getHeader("host").data()) {
                 return {HTTP_ERROR_400_BAD_REQUEST, FULLPTR};
@@ -611,11 +611,12 @@ namespace uWS
             * ought to be handled as an error. */
             std::string_view transferEncodingString = req->getHeader("transfer-encoding");
             std::string_view contentLengthString = req->getHeader("content-length");
+
             auto transferEncodingStringLen = transferEncodingString.length();
             auto contentLengthStringLen = contentLengthString.length();
             if (transferEncodingStringLen && contentLengthStringLen) {
                 /* Returning fullptr is the same as calling the errorHandler */
-                /* We could be smart and set an error in the context along with this, to indicate what 
+                /* We could be smart and set an error in the context along with this, to indicate what
                  * http error response we might want to return */
                 return {HTTP_ERROR_400_BAD_REQUEST, FULLPTR};
             }
@@ -623,7 +624,7 @@ namespace uWS
             /* Parse query */
             const char *querySeparatorPtr = (const char *) memchr(req->headers->value.data(), '?', req->headers->value.length());
             req->querySeparator = (unsigned int) ((querySeparatorPtr ? querySeparatorPtr : req->headers->value.data() + req->headers->value.length()) - req->headers->value.data());
-            
+
             // lets check if content len is valid before calling requestHandler
             if(contentLengthStringLen) {
                 remainingStreamingBytes = toUnsignedInteger(contentLengthString);
@@ -633,6 +634,14 @@ namespace uWS
                 }
             }
 
+            // lets check if content len is valid before calling requestHandler
+            if(contentLengthStringLen) {
+                remainingStreamingBytes = toUnsignedInteger(contentLengthString);
+                if (remainingStreamingBytes == UINT64_MAX) {
+                    /* Parser error */
+                    return {HTTP_ERROR_400_BAD_REQUEST, FULLPTR};
+                }
+            }
             /* If returned socket is not what we put in we need
              * to break here as we either have upgraded to
              * WebSockets or otherwise closed the socket. */
@@ -654,7 +663,7 @@ namespace uWS
             if (transferEncodingStringLen) {
 
                 /* If a proxy sent us the transfer-encoding header that 100% means it must be chunked or else the proxy is
-                 * not RFC 9112 compliant. Therefore it is always better to assume this is the case, since that entirely eliminates 
+                 * not RFC 9112 compliant. Therefore it is always better to assume this is the case, since that entirely eliminates
                  * all forms of transfer-encoding obfuscation tricks. We just rely on the header. */
 
                 /* RFC 9112 6.3
@@ -683,7 +692,6 @@ namespace uWS
                     consumedTotal += consumed;
                 }
             } else if (contentLengthStringLen) {
-              
                 if constexpr (!ConsumeMinimally) {
                     unsigned int emittable = (unsigned int) std::min<uint64_t>(remainingStreamingBytes, length);
                     dataHandler(user, std::string_view(data, emittable), emittable == remainingStreamingBytes);

packages/bun-uws/src/HttpResponse.h

@@ -81,8 +81,12 @@ public:
 
     /* Called only once per request */
     void writeMark() {
+        if (getHttpResponseData()->state & HttpResponseData<SSL>::HTTP_WROTE_DATE_HEADER) {
+            return;
+        }
         /* Date is always written */
         writeHeader("Date", std::string_view(((LoopData *) us_loop_ext(us_socket_context_loop(SSL, (us_socket_context(SSL, (us_socket_t *) this)))))->date, 29));
+        getHttpResponseData()->state |= HttpResponseData<SSL>::HTTP_WROTE_DATE_HEADER;
     }
 
     /* Returns true on success, indicating that it might be feasible to write more data.
@@ -113,7 +117,8 @@ public:
             httpResponseData->state |= HttpResponseData<SSL>::HTTP_CONNECTION_CLOSE;
         }
 
-        if (httpResponseData->state & HttpResponseData<SSL>::HTTP_WRITE_CALLED) {
+        /* if write was called and there was previously no Content-Length header set */
+        if (httpResponseData->state & HttpResponseData<SSL>::HTTP_WRITE_CALLED && !(httpResponseData->state & HttpResponseData<SSL>::HTTP_WROTE_CONTENT_LENGTH_HEADER) && !httpResponseData->fromAncientRequest) {
 
             /* We do not have tryWrite-like functionalities, so ignore optional in this path */
 
@@ -145,6 +150,8 @@ public:
                         }
                     }
                 }
+            } else {
+                this->uncork();
             }
 
             /* tryEnd can never fail when in chunked mode, since we do not have tryWrite (yet), only write */
@@ -152,7 +159,7 @@ public:
             return true;
         } else {
             /* Write content-length on first call */
-            if (!(httpResponseData->state & HttpResponseData<SSL>::HTTP_END_CALLED)) {
+            if (!(httpResponseData->state & (HttpResponseData<SSL>::HTTP_END_CALLED))) {
                 /* Write mark, this propagates to WebSockets too */
                 writeMark();
 
@@ -162,7 +169,8 @@ public:
                     Super::write("Content-Length: ", 16);
                     writeUnsigned64(totalSize);
                     Super::write("\r\n\r\n", 4);
-                } else {
+                    httpResponseData->state |= HttpResponseData<SSL>::HTTP_WROTE_CONTENT_LENGTH_HEADER;
+                } else if (!(httpResponseData->state & (HttpResponseData<SSL>::HTTP_WRITE_CALLED))) {
                     Super::write("\r\n", 2);
                 }
 
@@ -207,6 +215,8 @@ public:
                             }
                         }
                     }
+                }  else {
+                    this->uncork();
                 }
             }
 
@@ -231,7 +241,7 @@ public:
     /* Manually upgrade to WebSocket. Typically called in upgrade handler. Immediately calls open handler.
      * NOTE: Will invalidate 'this' as socket might change location in memory. Throw away after use. */
     template <typename UserData>
-    void upgrade(UserData &&userData, std::string_view secWebSocketKey, std::string_view secWebSocketProtocol,
+    us_socket_t *upgrade(UserData &&userData, std::string_view secWebSocketKey, std::string_view secWebSocketProtocol,
             std::string_view secWebSocketExtensions,
             struct us_socket_context_t *webSocketContext) {
 
@@ -313,8 +323,8 @@ public:
         bool wasCorked = Super::isCorked();
 
         /* Adopting a socket invalidates it, do not rely on it directly to carry any data */
-        WebSocket<SSL, true, UserData> *webSocket = (WebSocket<SSL, true, UserData> *) us_socket_context_adopt_socket(SSL,
-                    (us_socket_context_t *) webSocketContext, (us_socket_t *) this, sizeof(WebSocketData) + sizeof(UserData));
+        us_socket_t *usSocket = us_socket_context_adopt_socket(SSL, (us_socket_context_t *) webSocketContext, (us_socket_t *) this, sizeof(WebSocketData) + sizeof(UserData));
+        WebSocket<SSL, true, UserData> *webSocket = (WebSocket<SSL, true, UserData> *) usSocket;
 
         /* For whatever reason we were corked, update cork to the new socket */
         if (wasCorked) {
@@ -344,6 +354,8 @@ public:
         if (webSocketContextData->openHandler) {
             webSocketContextData->openHandler(webSocket);
         }
+
+        return usSocket;
     }
 
     /* Immediately terminate this Http response */
@@ -427,7 +439,7 @@ public:
 
     /* End the response with an optional data chunk. Always starts a timeout. */
     void end(std::string_view data = {}, bool closeConnection = false) {
-        internalEnd(data, data.length(), false, true, closeConnection);
+        internalEnd(data, data.length(), false, !(this->getHttpResponseData()->state & HttpResponseData<SSL>::HTTP_WROTE_CONTENT_LENGTH_HEADER), closeConnection);
     }
 
     /* Try and end the response. Returns [true, true] on success.
@@ -441,12 +453,12 @@ public:
     bool sendTerminatingChunk(bool closeConnection = false) {
         writeStatus(HTTP_200_OK);
         HttpResponseData<SSL> *httpResponseData = getHttpResponseData();
-        if (!(httpResponseData->state & HttpResponseData<SSL>::HTTP_WRITE_CALLED)) {
+        if (!(httpResponseData->state & (HttpResponseData<SSL>::HTTP_WRITE_CALLED | HttpResponseData<SSL>::HTTP_WROTE_CONTENT_LENGTH_HEADER))) {
             /* Write mark on first call to write */
             writeMark();
 
             writeHeader("Transfer-Encoding", "chunked");
-            httpResponseData->state |= HttpResponseData<SSL>::HTTP_WRITE_CALLED; 
+            httpResponseData->state |= HttpResponseData<SSL>::HTTP_WRITE_CALLED;
         }
 
         /* This will be sent always when state is HTTP_WRITE_CALLED inside internalEnd, so no need to write the terminating 0 chunk here */
@@ -456,33 +468,46 @@ public:
     }
 
     /* Write parts of the response in chunking fashion. Starts timeout if failed. */
-    bool write(std::string_view data) {
+    bool write(std::string_view data, size_t *writtenPtr = nullptr) {
         writeStatus(HTTP_200_OK);
 
         /* Do not allow sending 0 chunks, they mark end of response */
         if (data.empty()) {
+            if (writtenPtr) {
+                *writtenPtr = 0;
+            }
             /* If you called us, then according to you it was fine to call us so it's fine to still call us */
             return true;
         }
 
         HttpResponseData<SSL> *httpResponseData = getHttpResponseData();
 
-        if (!(httpResponseData->state & HttpResponseData<SSL>::HTTP_WRITE_CALLED)) {
-            /* Write mark on first call to write */
-            writeMark();
+        if (!(httpResponseData->state & HttpResponseData<SSL>::HTTP_WROTE_CONTENT_LENGTH_HEADER) && !httpResponseData->fromAncientRequest) {
+            if (!(httpResponseData->state & HttpResponseData<SSL>::HTTP_WRITE_CALLED)) {
+                /* Write mark on first call to write */
+                writeMark();
 
-            writeHeader("Transfer-Encoding", "chunked");
+                writeHeader("Transfer-Encoding", "chunked");
+                httpResponseData->state |= HttpResponseData<SSL>::HTTP_WRITE_CALLED;
+            }
+
+            Super::write("\r\n", 2);
+            writeUnsignedHex((unsigned int) data.length());
+            Super::write("\r\n", 2);
+        } else if (!(httpResponseData->state & HttpResponseData<SSL>::HTTP_WRITE_CALLED)) {
+            writeMark();
+            Super::write("\r\n", 2);
             httpResponseData->state |= HttpResponseData<SSL>::HTTP_WRITE_CALLED;
         }
 
-        Super::write("\r\n", 2);
-        writeUnsignedHex((unsigned int) data.length());
-        Super::write("\r\n", 2);
-
         auto [written, failed] = Super::write(data.data(), (int) data.length());
         /* Reset timeout on each sended chunk */
         this->resetTimeout();
 
+        if (writtenPtr) {
+            *writtenPtr = written;
+        }
+
         /* If we did not fail the write, accept more */
         return !failed;
     }
@@ -515,7 +540,7 @@ public:
             Super::cork();
             handler();
 
-            /* The only way we could possibly have changed the corked socket during handler call, would be if 
+            /* The only way we could possibly have changed the corked socket during handler call, would be if
              * the HTTP socket was upgraded to WebSocket and caused a realloc. Because of this we cannot use "this"
              * from here downwards. The corking is done with corkUnchecked() in upgrade. It steals cork. */
             auto *newCorkedSocket = loopData->getCorkedSocket();
@@ -582,7 +607,7 @@ public:
     /* Attach handler for aborted HTTP request */
     HttpResponse *onAborted(void* userData,  HttpResponseData<SSL>::OnAbortedCallback handler) {
         HttpResponseData<SSL> *httpResponseData = getHttpResponseData();
-        
+
         httpResponseData->userData = userData;
         httpResponseData->onAborted = handler;
         return this;
@@ -590,7 +615,7 @@ public:
 
     HttpResponse *onTimeout(void* userData,  HttpResponseData<SSL>::OnTimeoutCallback handler) {
         HttpResponseData<SSL> *httpResponseData = getHttpResponseData();
-        
+
         httpResponseData->userData = userData;
         httpResponseData->onTimeout = handler;
         return this;
@@ -620,7 +645,7 @@ public:
         return this;
     }
     /* Attach a read handler for data sent. Will be called with FIN set true if last segment. */
-    void onData(void* userData, HttpResponseData<SSL>::OnDataCallback handler) { 
+    void onData(void* userData, HttpResponseData<SSL>::OnDataCallback handler) {
         HttpResponseData<SSL> *data = getHttpResponseData();
         data->userData = userData;
         data->inStream = handler;
@@ -629,6 +654,17 @@ public:
         data->received_bytes_per_timeout = 0;
     }
 
+    void* getSocketData() {
+        HttpResponseData<SSL> *httpResponseData = getHttpResponseData();
+
+        return httpResponseData->socketData;
+    }
+
+    void setSocketData(void* socketData) {
+        HttpResponseData<SSL> *httpResponseData = getHttpResponseData();
+
+        httpResponseData->socketData = socketData;
+    }
 
     void setWriteOffset(uint64_t offset) {
         HttpResponseData<SSL> *httpResponseData = getHttpResponseData();

packages/bun-uws/src/HttpResponseData.h

@@ -36,7 +36,7 @@ struct HttpResponseData : AsyncSocketData<SSL>, HttpParser {
     using OnAbortedCallback = void (*)(uWS::HttpResponse<SSL>*, void*);
     using OnTimeoutCallback = void (*)(uWS::HttpResponse<SSL>*, void*);
     using OnDataCallback = void (*)(uWS::HttpResponse<SSL>* response, const char* chunk, size_t chunk_length, bool, void*);
-    
+
     /* When we are done with a response we mark it like so */
     void markDone() {
         onAborted = nullptr;
@@ -53,7 +53,7 @@ struct HttpResponseData : AsyncSocketData<SSL>, HttpParser {
     }
 
     /* Caller of onWritable. It is possible onWritable calls markDone so we need to borrow it. */
-    bool callOnWritable( uWS::HttpResponse<SSL>* response, uint64_t offset) {
+    bool callOnWritable(uWS::HttpResponse<SSL>* response, uint64_t offset) {
         /* Borrow real onWritable */
         auto* borrowedOnWritable = std::move(onWritable);
 
@@ -77,11 +77,14 @@ struct HttpResponseData : AsyncSocketData<SSL>, HttpParser {
         HTTP_WRITE_CALLED = 2, // used
         HTTP_END_CALLED = 4, // used
         HTTP_RESPONSE_PENDING = 8, // used
-        HTTP_CONNECTION_CLOSE = 16 // used
+        HTTP_CONNECTION_CLOSE = 16, // used
+        HTTP_WROTE_CONTENT_LENGTH_HEADER = 32, // used
+        HTTP_WROTE_DATE_HEADER = 64, // used
     };
 
     /* Shared context pointer */
     void* userData = nullptr;
+    void* socketData = nullptr;
 
     /* Per socket event handlers */
     OnWritableCallback onWritable = nullptr;
@@ -97,6 +100,7 @@ struct HttpResponseData : AsyncSocketData<SSL>, HttpParser {
     /* Current state (content-length sent, status sent, write called, etc */
     uint8_t state = 0;
     uint8_t idleTimeout = 10; // default HTTP_TIMEOUT 10 seconds
+    bool fromAncientRequest = false;
 
 #ifdef UWS_WITH_PROXY
     ProxyParser proxyParser;

packages/bun-uws/src/Loop.h

@@ -24,6 +24,7 @@
 #include "LoopData.h"
 #include <libusockets.h>
 #include <iostream>
+#include "AsyncSocket.h"
 
 extern "C" int bun_is_exiting();
 
@@ -52,6 +53,15 @@ private:
         for (auto &p : loopData->preHandlers) {
             p.second((Loop *) loop);
         }
+
+        void *corkedSocket = loopData->getCorkedSocket();
+        if (corkedSocket) {
+            if (loopData->isCorkedSSL()) {
+                ((uWS::AsyncSocket<true> *) corkedSocket)->uncork();
+            } else {
+                ((uWS::AsyncSocket<false> *) corkedSocket)->uncork();
+            }
+        }
     }
 
     static void postCb(us_loop_t *loop) {
@@ -148,6 +158,10 @@ public:
         getLazyLoop().loop = nullptr;
     }
 
+    static LoopData* data(struct us_loop_t *loop) {
+        return (LoopData *) us_loop_ext(loop);
+    }
+
     void addPostHandler(void *key, MoveOnlyFunction<void(Loop *)> &&handler) {
         LoopData *loopData = (LoopData *) us_loop_ext((us_loop_t *) this);
 

packages/bun-uws/src/LoopData.h

@@ -63,6 +63,7 @@ public:
         }
         delete [] corkBuffer;
     }
+
     void* getCorkedSocket() {
         return this->corkedSocket;
     }

packages/bun-uws/src/MoveOnlyFunction.h

@@ -82,7 +82,14 @@ namespace ofats {
 
 namespace any_detail {
 
-using buffer = std::aligned_storage_t<sizeof(void*) * 2, alignof(void*)>;
+template <std::size_t Len, std::size_t Align>
+class my_aligned_storage_t {
+private:
+    alignas(Align) std::byte t_buff[Len];
+};
+
+
+using buffer = my_aligned_storage_t<sizeof(void*) * 2, alignof(void*)>;
 
 template <class T>
 inline constexpr bool is_small_object_v =

packages/bun-uws/src/WebSocket.h

@@ -115,7 +115,7 @@ public:
             char header[10];
             int header_length = (int) protocol::formatMessage<isServer>(header, "", 0, opCode, message.length(), compress, fin);
             int written = us_socket_write2(0, (struct us_socket_t *)this, header, header_length, message.data(), (int) message.length());
-        
+
             if (written != header_length + (int) message.length()) {
                 /* Buffer up backpressure */
                 if (written > header_length) {
@@ -289,7 +289,7 @@ public:
         );
 
         WebSocketData *webSocketData = (WebSocketData *) us_socket_ext(SSL, (us_socket_t *) this);
-        
+
         if (!webSocketData->subscriber) { return false; }
 
         /* Cannot return numSubscribers as this is only for this particular websocket context */

packages/bun-uws/src/WebSocketContextData.h

@@ -82,7 +82,7 @@ public:
     std::pair<unsigned short, unsigned short> idleTimeoutComponents;
 
     /* This is run once on start-up */
-    void calculateIdleTimeoutCompnents(unsigned short idleTimeout) {
+    void calculateIdleTimeoutComponents(unsigned short idleTimeout) {
         unsigned short margin = 4;
         /* 4, 8 or 16 seconds margin based on idleTimeout */
         while ((int) idleTimeout - margin * 2 >= margin * 2 && margin < 16) {

scripts/bootstrap.ps1

@@ -345,7 +345,7 @@ function Install-Rust {
 function Install-Llvm {
   Install-Package llvm `
     -Command clang-cl `
-    -Version "18.1.8"
+    -Version "19.1.7"
   Add-To-Path "$env:ProgramFiles\LLVM\bin"
 }
 

scripts/bootstrap.sh

@@ -1,5 +1,5 @@
 #!/bin/sh
-# Version: 9
+# Version: 10
 
 # A script that installs the dependencies needed to build and test Bun.
 # This should work on macOS and Linux with a POSIX shell.
@@ -897,7 +897,7 @@ install_build_essentials() {
 }
 
 llvm_version_exact() {
-	print "18.1.8"
+	print "19.1.7"
 }
 
 llvm_version() {
@@ -915,14 +915,12 @@ install_llvm() {
 		install_packages "llvm@$(llvm_version)"
 		;;
 	apk)
+		# alpine doesn't have a lld19 package on 3.21 atm so use bare one for now
 		install_packages \
 			"llvm$(llvm_version)" \
 			"clang$(llvm_version)" \
 			"scudo-malloc" \
-			--repository "http://dl-cdn.alpinelinux.org/alpine/edge/main"
-		install_packages \
-			"lld$(llvm_version)" \
-			--repository "http://dl-cdn.alpinelinux.org/alpine/edge/community"
+			"lld"
 		;;
 	esac
 }
@@ -966,7 +964,7 @@ install_gcc() {
 		;;
 	esac
 
-	llvm_v="18"
+	llvm_v="19"
 
 	append_to_profile "export CC=clang-${llvm_v}"
 	append_to_profile "export CXX=clang++-${llvm_v}"
@@ -1132,6 +1130,35 @@ install_tailscale() {
 	esac
 }
 
+install_fuse_python() {
+	# only linux needs this
+	case "$pm" in
+	apk)
+		# Build and install from source (https://github.com/libfuse/python-fuse/blob/master/INSTALL)
+		install_packages \
+			python3-dev \
+			fuse-dev \
+			pkgconf \
+			py3-setuptools
+		python_fuse_version="1.0.9"
+		python_fuse_tarball=$(download_file "https://github.com/libfuse/python-fuse/archive/refs/tags/v$python_fuse_version.tar.gz")
+		python_fuse_tmpdir="$(dirname "$python_fuse_tarball")"
+		execute tar -xzf "$python_fuse_tarball" -C "$python_fuse_tmpdir"
+		execute sh -c "cd '$python_fuse_tmpdir/python-fuse-$python_fuse_version' && python setup.py build"
+		execute_sudo sh -c "cd '$python_fuse_tmpdir/python-fuse-$python_fuse_version' && python setup.py install"
+
+		# For Alpine we also need to make sure the kernel module is automatically loaded
+		execute_sudo sh -c "echo fuse >> /etc/modules-load.d/fuse.conf"
+
+		# Check that it was actually installed
+		execute python -c 'import fuse'
+		;;
+	apt | dnf | yum)
+		install_packages python3-fuse
+		;;
+	esac
+}
+
 create_buildkite_user() {
 	if ! [ "$ci" = "1" ] || ! [ "$os" = "linux" ]; then
 		return
@@ -1323,6 +1350,7 @@ main() {
 	install_common_software
 	install_build_essentials
 	install_chromium
+	install_fuse_python
 	clean_system
 }
 

scripts/runner.node.mjs

@@ -256,13 +256,15 @@ async function runTests() {
     for (const testPath of tests) {
       const absoluteTestPath = join(testsPath, testPath);
       const title = relative(cwd, absoluteTestPath).replaceAll(sep, "/");
-      if (isNodeParallelTest(testPath)) {
-        const runWithBunTest = title.includes("needs-test") || readFileSync(absoluteTestPath, "utf-8").includes('bun:test');
+      if (isNodeTest(testPath)) {
+        const testContent = readFileSync(absoluteTestPath, "utf-8");
+        const runWithBunTest =
+          title.includes("needs-test") || testContent.includes("bun:test") || testContent.includes("node:test");
         const subcommand = runWithBunTest ? "test" : "run";
         await runTest(title, async () => {
           const { ok, error, stdout } = await spawnBun(execPath, {
             cwd: cwd,
-            args: [subcommand, "--config=./bunfig.node-test.toml", absoluteTestPath],
+            args: [subcommand, "--config=" + join(import.meta.dirname, "../bunfig.node-test.toml"), absoluteTestPath],
             timeout: getNodeParallelTestTimeout(title),
             env: {
               FORCE_COLOR: "0",
@@ -870,19 +872,26 @@ function isJavaScriptTest(path) {
 }
 
 /**
- * @param {string} testPath
+ * @param {string} path
  * @returns {boolean}
  */
-function isNodeParallelTest(testPath) {
-  return testPath.replaceAll(sep, "/").includes("js/node/test/parallel/");
+function isNodeTest(path) {
+  // Do not run node tests on macOS x64 in CI
+  // TODO: Unclear why we decided to do this?
+  if (isCI && isMacOS && isX64) {
+    return false;
+  }
+  const unixPath = path.replaceAll(sep, "/");
+  return unixPath.includes("js/node/test/parallel/") || unixPath.includes("js/node/test/sequential/");
 }
 
 /**
- * @param {string} testPath
+ * @param {string} path
  * @returns {boolean}
  */
-function isNodeSequentialTest(testPath) {
-  return testPath.replaceAll(sep, "/").includes("js/node/test/sequential/");
+function isClusterTest(path) {
+  const unixPath = path.replaceAll(sep, "/");
+  return unixPath.includes("js/node/cluster/test-") && unixPath.endsWith(".ts");
 }
 
 /**
@@ -890,21 +899,17 @@ function isNodeSequentialTest(testPath) {
  * @returns {boolean}
  */
 function isTest(path) {
-  if (isNodeParallelTest(path) && targetDoesRunNodeTests()) return true;
-  if (isNodeSequentialTest(path) && targetDoesRunNodeTests()) return true;
-  if (path.replaceAll(sep, "/").startsWith("js/node/cluster/test-") && path.endsWith(".ts")) return true;
-  return isTestStrict(path);
+  return isNodeTest(path) || isClusterTest(path) ? true : isTestStrict(path);
 }
 
+/**
+ * @param {string} path
+ * @returns {boolean}
+ */
 function isTestStrict(path) {
   return isJavaScript(path) && /\.test|spec\./.test(basename(path));
 }
 
-function targetDoesRunNodeTests() {
-  if (isMacOS && isX64) return false;
-  return true;
-}
-
 /**
  * @param {string} path
  * @returns {boolean}

src/StandaloneModuleGraph.zig

@@ -466,11 +466,7 @@ pub const StandaloneModuleGraph = struct {
         return output_bytes;
     }
 
-    const page_size = if (Environment.isLinux and Environment.isAarch64)
-        // some linux distros do 64 KB pages on aarch64
-        64 * 1024
-    else
-        std.mem.page_size;
+    const page_size = std.heap.page_size_max;
 
     pub const InjectOptions = struct {
         windows_hide_console: bool = false,

src/allocators/AllocationScope.zig

@@ -74,16 +74,17 @@ pub fn allocator(scope: *AllocationScope) Allocator {
 const vtable: Allocator.VTable = .{
     .alloc = alloc,
     .resize = resize,
+    .remap = remap,
     .free = free,
 };
 
-fn alloc(ctx: *anyopaque, len: usize, ptr_align: u8, ret_addr: usize) ?[*]u8 {
+fn alloc(ctx: *anyopaque, len: usize, alignment: std.mem.Alignment, ret_addr: usize) ?[*]u8 {
     const scope: *AllocationScope = @ptrCast(@alignCast(ctx));
     scope.state.mutex.lock();
     defer scope.state.mutex.unlock();
     scope.state.allocations.ensureUnusedCapacity(scope.parent, 1) catch
         return null;
-    const result = scope.parent.vtable.alloc(scope.parent.ptr, len, ptr_align, ret_addr) orelse
+    const result = scope.parent.vtable.alloc(scope.parent.ptr, len, alignment, ret_addr) orelse
         return null;
     const trace = StoredTrace.capture(ret_addr);
     scope.state.allocations.putAssumeCapacityNoClobber(result, .{
@@ -94,12 +95,17 @@ fn alloc(ctx: *anyopaque, len: usize, ptr_align: u8, ret_addr: usize) ?[*]u8 {
     return result;
 }
 
-fn resize(ctx: *anyopaque, buf: []u8, buf_align: u8, new_len: usize, ret_addr: usize) bool {
+fn resize(ctx: *anyopaque, buf: []u8, alignment: std.mem.Alignment, new_len: usize, ret_addr: usize) bool {
     const scope: *AllocationScope = @ptrCast(@alignCast(ctx));
-    return scope.parent.vtable.resize(scope.parent.ptr, buf, buf_align, new_len, ret_addr);
+    return scope.parent.vtable.resize(scope.parent.ptr, buf, alignment, new_len, ret_addr);
 }
 
-fn free(ctx: *anyopaque, buf: []u8, buf_align: u8, ret_addr: usize) void {
+fn remap(ctx: *anyopaque, buf: []u8, alignment: std.mem.Alignment, new_len: usize, ret_addr: usize) ?[*]u8 {
+    const scope: *AllocationScope = @ptrCast(@alignCast(ctx));
+    return scope.parent.vtable.remap(scope.parent.ptr, buf, alignment, new_len, ret_addr);
+}
+
+fn free(ctx: *anyopaque, buf: []u8, alignment: std.mem.Alignment, ret_addr: usize) void {
     const scope: *AllocationScope = @ptrCast(@alignCast(ctx));
     scope.state.mutex.lock();
     defer scope.state.mutex.unlock();
@@ -137,7 +143,7 @@ fn free(ctx: *anyopaque, buf: []u8, buf_align: u8, ret_addr: usize) void {
         // sanitizer does not catch the invalid free.
     }
 
-    scope.parent.vtable.free(scope.parent.ptr, buf, buf_align, ret_addr);
+    scope.parent.vtable.free(scope.parent.ptr, buf, alignment, ret_addr);
 
     // If asan did not catch the free, panic now.
     if (invalid) @panic("Invalid free");

src/allocators/NullableAllocator.zig

@@ -33,7 +33,7 @@ pub fn free(this: *const NullableAllocator, bytes: []const u8) void {
     if (this.get()) |allocator| {
         if (bun.String.isWTFAllocator(allocator)) {
             // workaround for https://github.com/ziglang/zig/issues/4298
-            bun.String.StringImplAllocator.free(allocator.ptr, @constCast(bytes), 0, 0);
+            bun.String.StringImplAllocator.free(allocator.ptr, @constCast(bytes), .fromByteUnits(1), 0);
             return;
         }
 

src/allocators/linux_memfd_allocator.zig

@@ -62,19 +62,15 @@ pub const LinuxMemFdAllocator = struct {
     }
 
     const AllocatorInterface = struct {
-        fn alloc(_: *anyopaque, _: usize, _: u8, _: usize) ?[*]u8 {
+        fn alloc(_: *anyopaque, _: usize, _: std.mem.Alignment, _: usize) ?[*]u8 {
             // it should perform no allocations or resizes
             return null;
         }
 
-        fn resize(_: *anyopaque, _: []u8, _: u8, _: usize, _: usize) bool {
-            return false;
-        }
-
         fn free(
             ptr: *anyopaque,
             buf: []u8,
-            _: u8,
+            _: std.mem.Alignment,
             _: usize,
         ) void {
             var this: *LinuxMemFdAllocator = @alignCast(@ptrCast(ptr));
@@ -86,7 +82,8 @@ pub const LinuxMemFdAllocator = struct {
 
         pub const VTable = &std.mem.Allocator.VTable{
             .alloc = &AllocatorInterface.alloc,
-            .resize = &resize,
+            .resize = &std.mem.Allocator.noResize,
+            .remap = &std.mem.Allocator.noRemap,
             .free = &free,
         };
     };
@@ -95,7 +92,7 @@ pub const LinuxMemFdAllocator = struct {
         var size = len;
 
         // size rounded up to nearest page
-        size += (size + std.mem.page_size - 1) & std.mem.page_size;
+        size = std.mem.alignForward(usize, size, std.heap.pageSize());
 
         var flags_mut = flags;
         flags_mut.TYPE = .SHARED;

src/allocators/max_heap_allocator.zig

@@ -4,9 +4,10 @@ const std = @import("std");
 /// Single allocation only.
 ///
 pub const MaxHeapAllocator = struct {
-    array_list: std.ArrayList(u8),
+    array_list: std.ArrayListAligned(u8, @alignOf(std.c.max_align_t)),
 
-    fn alloc(ptr: *anyopaque, len: usize, _: u8, _: usize) ?[*]u8 {
+    fn alloc(ptr: *anyopaque, len: usize, alignment: std.mem.Alignment, _: usize) ?[*]u8 {
+        bun.assert(alignment.toByteUnits() <= @alignOf(std.c.max_align_t));
         var this = bun.cast(*MaxHeapAllocator, ptr);
         this.array_list.items.len = 0;
         this.array_list.ensureTotalCapacity(len) catch return null;
@@ -14,7 +15,7 @@ pub const MaxHeapAllocator = struct {
         return this.array_list.items.ptr;
     }
 
-    fn resize(_: *anyopaque, buf: []u8, _: u8, new_len: usize, _: usize) bool {
+    fn resize(_: *anyopaque, buf: []u8, _: std.mem.Alignment, new_len: usize, _: usize) bool {
         _ = new_len;
         _ = buf;
         @panic("not implemented");
@@ -23,7 +24,7 @@ pub const MaxHeapAllocator = struct {
     fn free(
         _: *anyopaque,
         _: []u8,
-        _: u8,
+        _: std.mem.Alignment,
         _: usize,
     ) void {}
 
@@ -39,9 +40,10 @@ pub const MaxHeapAllocator = struct {
         .alloc = &alloc,
         .free = &free,
         .resize = &resize,
+        .remap = &std.mem.Allocator.noRemap,
     };
     pub fn init(this: *MaxHeapAllocator, allocator: std.mem.Allocator) std.mem.Allocator {
-        this.array_list = std.ArrayList(u8).init(allocator);
+        this.array_list = .init(allocator);
 
         return std.mem.Allocator{
             .ptr = this,

src/allocators/memory_allocator.zig

@@ -12,7 +12,7 @@ const Environment = @import("../env.zig");
 fn mimalloc_free(
     _: *anyopaque,
     buf: []u8,
-    buf_align: u8,
+    alignment: mem.Alignment,
     _: usize,
 ) void {
     if (comptime Environment.enable_logs)
@@ -23,8 +23,8 @@ fn mimalloc_free(
     // let's only enable it in debug mode
     if (comptime Environment.isDebug) {
         assert(mimalloc.mi_is_in_heap_region(buf.ptr));
-        if (mimalloc.canUseAlignedAlloc(buf.len, buf_align))
-            mimalloc.mi_free_size_aligned(buf.ptr, buf.len, buf_align)
+        if (mimalloc.canUseAlignedAlloc(buf.len, alignment.toByteUnits()))
+            mimalloc.mi_free_size_aligned(buf.ptr, buf.len, alignment.toByteUnits())
         else
             mimalloc.mi_free_size(buf.ptr, buf.len);
     } else {
@@ -35,12 +35,12 @@ fn mimalloc_free(
 const CAllocator = struct {
     pub const supports_posix_memalign = true;
 
-    fn alignedAlloc(len: usize, alignment: usize) ?[*]u8 {
+    fn alignedAlloc(len: usize, alignment: mem.Alignment) ?[*]u8 {
         if (comptime Environment.enable_logs)
-            log("mi_alloc({d}, {d})", .{ len, alignment });
+            log("mi_alloc({d}, {d})", .{ len, alignment.toByteUnits() });
 
-        const ptr: ?*anyopaque = if (mimalloc.canUseAlignedAlloc(len, alignment))
-            mimalloc.mi_malloc_aligned(len, alignment)
+        const ptr: ?*anyopaque = if (mimalloc.canUseAlignedAlloc(len, alignment.toByteUnits()))
+            mimalloc.mi_malloc_aligned(len, alignment.toByteUnits())
         else
             mimalloc.mi_malloc(len);
 
@@ -60,16 +60,11 @@ const CAllocator = struct {
         return mimalloc.mi_malloc_size(ptr);
     }
 
-    fn alloc(_: *anyopaque, len: usize, log2_align: u8, _: usize) ?[*]u8 {
-        if (comptime FeatureFlags.alignment_tweak) {
-            return alignedAlloc(len, log2_align);
-        }
-
-        const alignment = @as(usize, 1) << @as(Allocator.Log2Align, @intCast(log2_align));
+    fn alloc(_: *anyopaque, len: usize, alignment: mem.Alignment, _: usize) ?[*]u8 {
         return alignedAlloc(len, alignment);
     }
 
-    fn resize(_: *anyopaque, buf: []u8, _: u8, new_len: usize, _: usize) bool {
+    fn resize(_: *anyopaque, buf: []u8, _: mem.Alignment, new_len: usize, _: usize) bool {
         if (new_len <= buf.len) {
             return true;
         }
@@ -93,17 +88,18 @@ pub const c_allocator = Allocator{
 const c_allocator_vtable = &Allocator.VTable{
     .alloc = &CAllocator.alloc,
     .resize = &CAllocator.resize,
+    .remap = &std.mem.Allocator.noRemap,
     .free = &CAllocator.free,
 };
 
 const ZAllocator = struct {
     pub const supports_posix_memalign = true;
 
-    fn alignedAlloc(len: usize, alignment: usize) ?[*]u8 {
+    fn alignedAlloc(len: usize, alignment: mem.Alignment) ?[*]u8 {
         log("ZAllocator.alignedAlloc: {d}\n", .{len});
 
-        const ptr = if (mimalloc.canUseAlignedAlloc(len, alignment))
-            mimalloc.mi_zalloc_aligned(len, alignment)
+        const ptr = if (mimalloc.canUseAlignedAlloc(len, alignment.toByteUnits()))
+            mimalloc.mi_zalloc_aligned(len, alignment.toByteUnits())
         else
             mimalloc.mi_zalloc(len);
 
@@ -123,11 +119,11 @@ const ZAllocator = struct {
         return mimalloc.mi_malloc_size(ptr);
     }
 
-    fn alloc(_: *anyopaque, len: usize, ptr_align: u8, _: usize) ?[*]u8 {
-        return alignedAlloc(len, ptr_align);
+    fn alloc(_: *anyopaque, len: usize, alignment: mem.Alignment, _: usize) ?[*]u8 {
+        return alignedAlloc(len, alignment);
     }
 
-    fn resize(_: *anyopaque, buf: []u8, _: u8, new_len: usize, _: usize) bool {
+    fn resize(_: *anyopaque, buf: []u8, _: mem.Alignment, new_len: usize, _: usize) bool {
         if (new_len <= buf.len) {
             return true;
         }
@@ -150,6 +146,7 @@ pub const z_allocator = Allocator{
 const z_allocator_vtable = Allocator.VTable{
     .alloc = &ZAllocator.alloc,
     .resize = &ZAllocator.resize,
+    .remap = &std.mem.Allocator.noRemap,
     .free = &ZAllocator.free,
 };
 const HugeAllocator = struct {

src/allocators/mimalloc_arena.zig

@@ -209,11 +209,11 @@ pub const Arena = struct {
     }
     pub const supports_posix_memalign = true;
 
-    fn alignedAlloc(heap: *mimalloc.Heap, len: usize, alignment: usize) ?[*]u8 {
+    fn alignedAlloc(heap: *mimalloc.Heap, len: usize, alignment: mem.Alignment) ?[*]u8 {
         log("Malloc: {d}\n", .{len});
 
-        const ptr: ?*anyopaque = if (mimalloc.canUseAlignedAlloc(len, alignment))
-            mimalloc.mi_heap_malloc_aligned(heap, len, alignment)
+        const ptr: ?*anyopaque = if (mimalloc.canUseAlignedAlloc(len, alignment.toByteUnits()))
+            mimalloc.mi_heap_malloc_aligned(heap, len, alignment.toByteUnits())
         else
             mimalloc.mi_heap_malloc(heap, len);
 
@@ -234,15 +234,10 @@ pub const Arena = struct {
         return mimalloc.mi_malloc_usable_size(ptr);
     }
 
-    fn alloc(arena: *anyopaque, len: usize, log2_align: u8, _: usize) ?[*]u8 {
+    fn alloc(arena: *anyopaque, len: usize, alignment: mem.Alignment, _: usize) ?[*]u8 {
         const this = bun.cast(*mimalloc.Heap, arena);
         // if (comptime Environment.isDebug)
         //     ArenaRegistry.assert(.{ .heap = this });
-        if (comptime FeatureFlags.alignment_tweak) {
-            return alignedAlloc(this, len, log2_align);
-        }
-
-        const alignment = @as(usize, 1) << @as(Allocator.Log2Align, @intCast(log2_align));
 
         return alignedAlloc(
             this,
@@ -251,7 +246,7 @@ pub const Arena = struct {
         );
     }
 
-    fn resize(_: *anyopaque, buf: []u8, _: u8, new_len: usize, _: usize) bool {
+    fn resize(_: *anyopaque, buf: []u8, _: mem.Alignment, new_len: usize, _: usize) bool {
         if (new_len <= buf.len) {
             return true;
         }
@@ -267,7 +262,7 @@ pub const Arena = struct {
     fn free(
         _: *anyopaque,
         buf: []u8,
-        buf_align: u8,
+        alignment: mem.Alignment,
         _: usize,
     ) void {
         // mi_free_size internally just asserts the size
@@ -275,8 +270,8 @@ pub const Arena = struct {
         // but its good to have that assertion
         if (comptime Environment.isDebug) {
             assert(mimalloc.mi_is_in_heap_region(buf.ptr));
-            if (mimalloc.canUseAlignedAlloc(buf.len, buf_align))
-                mimalloc.mi_free_size_aligned(buf.ptr, buf.len, buf_align)
+            if (mimalloc.canUseAlignedAlloc(buf.len, alignment.toByteUnits()))
+                mimalloc.mi_free_size_aligned(buf.ptr, buf.len, alignment.toByteUnits())
             else
                 mimalloc.mi_free_size(buf.ptr, buf.len);
         } else {
@@ -288,5 +283,6 @@ pub const Arena = struct {
 const c_allocator_vtable = Allocator.VTable{
     .alloc = &Arena.alloc,
     .resize = &Arena.resize,
+    .remap = &std.mem.Allocator.noRemap,
     .free = &Arena.free,
 };

src/analytics/analytics_thread.zig

@@ -128,6 +128,8 @@ pub const Features = struct {
     pub var process_dlopen: usize = 0;
     pub var postgres_connections: usize = 0;
     pub var s3: usize = 0;
+    pub var csrf_verify: usize = 0;
+    pub var csrf_generate: usize = 0;
 
     comptime {
         @export(&napi_module_register, .{ .name = "Bun__napi_module_register_count" });

src/async/windows_event_loop.zig

@@ -187,7 +187,7 @@ pub const FilePoll = struct {
 
     pub fn unregister(this: *FilePoll, loop: *Loop) bool {
         _ = loop;
-        // TODO(@paperdave): This cast is extremely suspicious. At best, `fd` is
+        // TODO(@paperclover): This cast is extremely suspicious. At best, `fd` is
         // the wrong type (it should be a uv handle), at worst this code is a
         // crash due to invalid memory access.
         uv.uv_unref(@ptrFromInt(@intFromEnum(this.fd)));

src/baby_list.zig

@@ -94,7 +94,7 @@ pub fn BabyList(comptime Type: type) type {
             this.update(list_);
         }
 
-        pub fn popOrNull(this: *@This()) ?Type {
+        pub fn pop(this: *@This()) ?Type {
             if (this.len == 0) return null;
             this.len -= 1;
             return this.ptr[this.len];

src/bake/DevServer.zig

@@ -10,6 +10,7 @@
 pub const DevServer = @This();
 pub const debug = bun.Output.Scoped(.DevServer, false);
 pub const igLog = bun.Output.scoped(.IncrementalGraph, false);
+const DebugHTTPServer = @import("../bun.js/api/server.zig").DebugHTTPServer;
 
 pub const Options = struct {
     /// Arena must live until DevServer.deinit()
@@ -99,6 +100,11 @@ server_register_update_callback: JSC.Strong,
 bun_watcher: *bun.Watcher,
 directory_watchers: DirectoryWatchStore,
 watcher_atomics: WatcherAtomics,
+testing_batch_events: union(enum) {
+    disabled,
+    enable_after_bundle,
+    enabled: TestingBatch,
+},
 
 /// Number of bundles that have been executed. This is currently not read, but
 /// will be used later to determine when to invoke graph garbage collection.
@@ -165,6 +171,9 @@ deferred_request_pool: bun.HiveArray(DeferredRequest.Node, DeferredRequest.max_p
 /// UWS can handle closing the websocket connections themselves
 active_websocket_connections: std.AutoHashMapUnmanaged(*HmrSocket, void),
 
+relative_path_buf_lock: bun.DebugThreadLock,
+relative_path_buf: bun.PathBuffer,
+
 // Debugging
 
 dump_dir: if (bun.FeatureFlags.bake_debugging_features) ?std.fs.Dir else void,
@@ -379,7 +388,7 @@ pub fn init(options: Options) bun.JSOOM!*DevServer {
         .emit_visualizer_events = 0,
         .has_pre_crash_handler = bun.FeatureFlags.bake_debugging_features and
             options.dump_state_on_crash orelse
-            bun.getRuntimeFeatureFlag("BUN_DUMP_STATE_ON_CRASH"),
+                bun.getRuntimeFeatureFlag("BUN_DUMP_STATE_ON_CRASH"),
         .frontend_only = options.framework.file_system_router_types.len == 0,
         .client_graph = .empty,
         .server_graph = .empty,
@@ -409,6 +418,8 @@ pub fn init(options: Options) bun.JSOOM!*DevServer {
                 true
         else
             bun.getRuntimeFeatureFlag("BUN_ASSUME_PERFECT_INCREMENTAL"),
+        .relative_path_buf_lock = .unlocked,
+        .testing_batch_events = .disabled,
 
         .server_transpiler = undefined,
         .client_transpiler = undefined,
@@ -419,6 +430,7 @@ pub fn init(options: Options) bun.JSOOM!*DevServer {
         .watcher_atomics = undefined,
         .log = undefined,
         .deferred_request_pool = undefined,
+        .relative_path_buf = undefined,
     });
     errdefer bun.destroy(dev);
     const allocator = dev.allocation_scope.allocator();
@@ -645,6 +657,8 @@ pub fn deinit(dev: *DevServer) void {
         .framework = {},
         .bundler_options = {},
         .assume_perfect_incremental_bundling = {},
+        .relative_path_buf = {},
+        .relative_path_buf_lock = {},
 
         .graph_safety_lock = dev.graph_safety_lock.lock(),
         .bun_watcher = dev.bun_watcher.deinit(true),
@@ -739,6 +753,13 @@ pub fn deinit(dev: *DevServer) void {
             event.aligned.files.deinit(dev.allocator);
             event.aligned.extra_files.deinit(dev.allocator);
         },
+        .testing_batch_events = switch (dev.testing_batch_events) {
+            .disabled => {},
+            .enabled => |*batch| {
+                batch.entry_points.deinit(allocator);
+            },
+            .enable_after_bundle => {},
+        },
     };
     dev.allocation_scope.deinit();
     bun.destroy(dev);
@@ -775,6 +796,8 @@ pub fn memoryCost(dev: *DevServer) usize {
         .server_register_update_callback = {},
         .deferred_request_pool = {},
         .assume_perfect_incremental_bundling = {},
+        .relative_path_buf = {},
+        .relative_path_buf_lock = {},
 
         // pointers that are not considered a part of DevServer
         .vm = {},
@@ -886,6 +909,13 @@ pub fn memoryCost(dev: *DevServer) usize {
         .route_lookup = {
             cost += memoryCostArrayHashMap(dev.route_lookup);
         },
+        .testing_batch_events = switch (dev.testing_batch_events) {
+            .disabled => {},
+            .enabled => |batch| {
+                cost += memoryCostArrayHashMap(batch.entry_points.set);
+            },
+            .enable_after_bundle => {},
+        },
     };
     return cost;
 }
@@ -915,7 +945,7 @@ fn initServerRuntime(dev: *DevServer) void {
     if (!interface.isObject()) @panic("Internal assertion failure: expected interface from HMR runtime to be an object");
     const fetch_function = interface.get(dev.vm.global, "handleRequest") catch null orelse
         @panic("Internal assertion failure: expected interface from HMR runtime to contain handleRequest");
-    bun.assert(fetch_function.isCallable(dev.vm.jsc));
+    bun.assert(fetch_function.isCallable());
     dev.server_fetch_function_callback = JSC.Strong.create(fetch_function, dev.vm.global);
     const register_update = interface.get(dev.vm.global, "registerUpdate") catch null orelse
         @panic("Internal assertion failure: expected interface from HMR runtime to contain registerUpdate");
@@ -1172,6 +1202,8 @@ fn ensureRouteIsBundled(
                     .loaded => {},
                 }
 
+                // TODO(@heimskr): store the request?
+
                 // Prepare a bundle with just this route.
                 var sfa = std.heap.stackFallback(4096, dev.allocator);
                 const temp_alloc = sfa.get();
@@ -1357,6 +1389,7 @@ fn onFrameworkRequestWithBundle(
             router_type.server_file_string.get() orelse str: {
                 const name = dev.server_graph.bundled_files.keys()[fromOpaqueFileId(.server, router_type.server_file).get()];
                 const str = bun.String.createUTF8ForJS(dev.vm.global, dev.relativePath(name));
+                dev.releaseRelativePathBuf();
                 router_type.server_file_string = JSC.Strong.create(str, dev.vm.global);
                 break :str str;
             },
@@ -1374,10 +1407,12 @@ fn onFrameworkRequestWithBundle(
                 route = dev.router.routePtr(bundle.route_index);
                 var route_name = bun.String.createUTF8(dev.relativePath(keys[fromOpaqueFileId(.server, route.file_page.unwrap().?).get()]));
                 arr.putIndex(global, 0, route_name.transferToJS(global));
+                dev.releaseRelativePathBuf();
                 n = 1;
                 while (true) {
                     if (route.file_layout.unwrap()) |layout| {
                         var layout_name = bun.String.createUTF8(dev.relativePath(keys[fromOpaqueFileId(.server, layout).get()]));
+                        defer dev.releaseRelativePathBuf();
                         arr.putIndex(global, @intCast(n), layout_name.transferToJS(global));
                         n += 1;
                     }
@@ -1858,7 +1893,7 @@ fn generateClientBundle(dev: *DevServer, route_bundle: *RouteBundle) bun.OOM![]u
             break :brk;
         if (!dev.client_graph.stale_files.isSet(rfr_index.get())) {
             try dev.client_graph.traceImports(rfr_index, &gts, .find_client_modules);
-            react_fast_refresh_id = dev.relativePath(rfr.import_source);
+            react_fast_refresh_id = rfr.import_source;
         }
     }
 
@@ -1881,7 +1916,7 @@ fn generateClientBundle(dev: *DevServer, route_bundle: *RouteBundle) bun.OOM![]u
     const client_bundle = dev.client_graph.takeJSBundle(.{
         .kind = .initial_response,
         .initial_response_entry_point = if (client_file) |index|
-            dev.relativePath(dev.client_graph.bundled_files.keys()[index.get()])
+            dev.client_graph.bundled_files.keys()[index.get()]
         else
             "",
         .react_refresh_entry_point = react_fast_refresh_id,
@@ -1961,6 +1996,7 @@ fn makeArrayForServerComponentsPatch(dev: *DevServer, global: *JSC.JSGlobalObjec
     const names = dev.server_graph.bundled_files.keys();
     for (items, 0..) |item, i| {
         const str = bun.String.createUTF8(dev.relativePath(names[item.get()]));
+        defer dev.releaseRelativePathBuf();
         defer str.deref();
         arr.putIndex(global, @intCast(i), str.toJS(global));
     }
@@ -2016,6 +2052,7 @@ pub fn finalizeBundle(
     bv2: *bun.bundle_v2.BundleV2,
     result: bun.bundle_v2.DevServerOutput,
 ) bun.OOM!void {
+    var had_sent_hmr_event = false;
     defer {
         bv2.deinit();
         dev.current_bundle = null;
@@ -2024,6 +2061,20 @@ pub fn finalizeBundle(
             // not fatal: the assets may be reindexed some time later.
         };
 
+        // Signal for testing framework where it is in synchronization
+        if (dev.testing_batch_events == .enable_after_bundle) {
+            dev.testing_batch_events = .{ .enabled = .empty };
+            dev.publish(.testing_watch_synchronization, &.{
+                MessageId.testing_watch_synchronization.char(),
+                0,
+            }, .binary);
+        } else {
+            dev.publish(.testing_watch_synchronization, &.{
+                MessageId.testing_watch_synchronization.char(),
+                if (had_sent_hmr_event) 4 else 3,
+            }, .binary);
+        }
+
         dev.startNextBundleIfPresent();
 
         // Unref the ref added in `startAsyncBundle`
@@ -2080,7 +2131,7 @@ pub fn finalizeBundle(
         .gts = undefined,
     };
 
-    const quoted_source_contents = bv2.linker.graph.files.items(.quoted_source_contents);
+    const quoted_source_contents: []const []const u8 = bv2.linker.graph.files.items(.quoted_source_contents);
     // Pass 1, update the graph's nodes, resolving every bundler source
     // index into its `IncrementalGraph(...).FileIndex`
     for (
@@ -2109,7 +2160,7 @@ pub fn finalizeBundle(
                 .{ .js = .{
                     .code = compile_result.code(),
                     .source_map = source_map,
-                    .quoted_contents = .initOwned(quoted_contents, dev.allocator),
+                    .quoted_contents = .initOwned(@constCast(quoted_contents), dev.allocator),
                 } },
                 graph == .ssr,
             ),
@@ -2192,7 +2243,7 @@ pub fn finalizeBundle(
             .{ .js = .{
                 .code = generated_js,
                 .source_map = .empty,
-                .quoted_contents = comptime .initNeverFree(""),
+                .quoted_contents = .empty,
             } },
             false,
         );
@@ -2249,6 +2300,11 @@ pub fn finalizeBundle(
     }
 
     // Index all failed files now that the incremental graph has been updated.
+    if (dev.incremental_result.failures_removed.items.len > 0 or
+        dev.incremental_result.failures_added.items.len > 0)
+    {
+        had_sent_hmr_event = true;
+    }
     try dev.indexFailures();
 
     try dev.client_graph.ensureStaleBitCapacity(false);
@@ -2327,7 +2383,7 @@ pub fn finalizeBundle(
     if (will_hear_hot_update and
         current_bundle.had_reload_event and
         (dev.incremental_result.framework_routes_affected.items.len +
-        dev.incremental_result.html_routes_hard_affected.items.len) > 0 and
+            dev.incremental_result.html_routes_hard_affected.items.len) > 0 and
         dev.bundling_failures.count() == 0)
     {
         has_route_bits_set = true;
@@ -2456,10 +2512,10 @@ pub fn finalizeBundle(
     }
     try w.writeInt(i32, -1, .little);
 
-    // Send CSS mutations
     const css_chunks = result.cssChunks();
     if (will_hear_hot_update) {
         if (dev.client_graph.current_chunk_len > 0 or css_chunks.len > 0) {
+            // Send CSS mutations
             const asset_values = dev.assets.files.values();
             try w.writeInt(u32, @intCast(css_chunks.len), .little);
             const sources = bv2.graph.input_files.items(.source);
@@ -2471,6 +2527,7 @@ pub fn finalizeBundle(
                 try w.writeAll(css_data);
             }
 
+            // Send the JS chunk
             if (dev.client_graph.current_chunk_len > 0) {
                 const hash = hash: {
                     var source_map_hash: bun.bundle_v2.ContentHasher.Hash = .init(0x4b12); // arbitrarily different seed than what .initial_response uses
@@ -2496,6 +2553,7 @@ pub fn finalizeBundle(
         }
 
         dev.publish(.hot_update, hot_update_payload.items, .binary);
+        had_sent_hmr_event = true;
     }
 
     if (dev.incremental_result.failures_added.items.len > 0) {
@@ -2575,6 +2633,7 @@ pub fn finalizeBundle(
                 break :file_name dev.relativePath(abs_path);
             },
         };
+        defer dev.releaseRelativePathBuf();
         const total_count = bv2.graph.entry_points.items.len;
         if (file_name) |name| {
             Output.prettyError("<d>:<r> {s}", .{name});
@@ -2642,7 +2701,9 @@ fn startNextBundleIfPresent(dev: *DevServer) void {
             dev.appendRouteEntryPointsIfNotStale(&entry_points, temp_alloc, route_bundle_index) catch bun.outOfMemory();
         }
 
-        dev.startAsyncBundle(entry_points, is_reload, timer) catch bun.outOfMemory();
+        if (entry_points.set.count() > 0) {
+            dev.startAsyncBundle(entry_points, is_reload, timer) catch bun.outOfMemory();
+        }
 
         dev.next_bundle.route_queue.clearRetainingCapacity();
     }
@@ -2770,16 +2831,13 @@ fn onRequest(dev: *DevServer, req: *Request, resp: anytype) void {
         return;
     }
 
-    switch (dev.server.?) {
-        inline else => |s| {
-            if (@typeInfo(@TypeOf(s.app.?)).pointer.child.Response != @typeInfo(@TypeOf(resp)).pointer.child) {
-                unreachable; // mismatch between `is_ssl` with server and response types. optimize these checks out.
-            }
-            if (s.config.onRequest != .zero) {
-                s.onRequest(req, resp);
-                return;
-            }
-        },
+    if (DevServer.AnyResponse != @typeInfo(@TypeOf(resp)).pointer.child) {
+        unreachable; // mismatch between `is_ssl` with server and response types. optimize these checks out.
+    }
+
+    if (dev.server.?.config.onRequest != .zero) {
+        dev.server.?.onRequest(req, resp);
+        return;
     }
 
     sendBuiltInNotFound(resp);
@@ -3244,15 +3302,15 @@ pub fn IncrementalGraph(side: bake.Side) type {
                 return self.vlq_ptr[0..self.vlq_len];
             }
 
-            pub fn quotedContentsCowString(self: @This()) bun.CowString {
-                return bun.CowString.initUnchecked(self.quoted_contents_ptr[0..self.quoted_contents_flags.len], self.quoted_contents_flags.is_owned);
+            pub fn quotedContentsCowString(self: @This()) bun.ptr.CowString {
+                return bun.ptr.CowString.initUnchecked(self.quoted_contents_ptr[0..self.quoted_contents_flags.len], self.quoted_contents_flags.is_owned);
             }
 
             pub fn quotedContents(self: @This()) []const u8 {
                 return self.quoted_contents_ptr[0..self.quoted_contents_flags.len];
             }
 
-            pub fn fromNonEmptySourceMap(source_map: SourceMap.Chunk, quoted_contents: bun.CowString) !PackedMap {
+            pub fn fromNonEmptySourceMap(source_map: SourceMap.Chunk, quoted_contents: bun.ptr.CowString) !PackedMap {
                 assert(source_map.buffer.list.items.len > 0);
                 return .{
                     .vlq_ptr = source_map.buffer.list.items.ptr,
@@ -3372,7 +3430,7 @@ pub fn IncrementalGraph(side: bake.Side) type {
                 js: struct {
                     code: []const u8,
                     source_map: SourceMap.Chunk,
-                    quoted_contents: bun.CowString,
+                    quoted_contents: bun.ptr.CowString,
                 },
                 css: u64,
             },
@@ -3698,7 +3756,7 @@ pub fn IncrementalGraph(side: bake.Side) type {
                 }
             }
 
-            while (queue.popOrNull()) |index| {
+            while (queue.pop()) |index| {
                 for (ctx.import_records[index.get()].slice()) |import_record| {
                     const result = try processEdgeAttachment(g, ctx, temp_alloc, quick_lookup, new_imports, file_index, import_record, .css);
                     if (result == .@"continue" and import_record.source_index.isValid()) {
@@ -4338,6 +4396,7 @@ pub fn IncrementalGraph(side: bake.Side) type {
                 dev.relativePath(gop.key_ptr.*),
                 log.msgs.items,
             );
+            defer dev.releaseRelativePathBuf();
             const fail_gop = try dev.bundling_failures.getOrPut(dev.allocator, failure);
             try dev.incremental_result.failures_added.append(dev.allocator, failure);
             if (fail_gop.found_existing) {
@@ -4556,6 +4615,7 @@ pub fn IncrementalGraph(side: bake.Side) type {
                                 w,
                                 .utf8,
                             );
+                            g.owner().releaseRelativePathBuf();
                         } else {
                             try w.writeAll("null");
                         }
@@ -4571,6 +4631,7 @@ pub fn IncrementalGraph(side: bake.Side) type {
                                 w,
                                 .utf8,
                             );
+                            g.owner().releaseRelativePathBuf();
                         }
                         try w.writeAll("\n");
                     },
@@ -4648,21 +4709,32 @@ pub fn IncrementalGraph(side: bake.Side) type {
             var source_map_strings = std.ArrayList(u8).init(arena);
             defer source_map_strings.deinit();
 
+            const dev = g.owner();
+            dev.relative_path_buf_lock.lock();
+            defer dev.relative_path_buf_lock.unlock();
+
+            const buf = bun.PathBufferPool.get();
+            defer bun.PathBufferPool.put(buf);
+
             var path_count: usize = 0;
             for (g.current_chunk_parts.items) |entry| {
                 path_count += 1;
                 try source_map_strings.appendSlice(",");
-                const path = paths[entry.get()];
+                const path = if (Environment.isWindows)
+                    bun.path.pathToPosixBuf(u8, paths[entry.get()], buf)
+                else
+                    paths[entry.get()];
+
                 if (std.fs.path.isAbsolute(path)) {
-                    const is_windows_drive_path = Environment.isWindows and bun.path.isSepAny(path[0]);
+                    const is_windows_drive_path = Environment.isWindows and path[0] != '/';
                     try source_map_strings.appendSlice(if (is_windows_drive_path)
-                        "file:///"
+                        "\"file:///"
                     else
                         "\"file://");
                     if (Environment.isWindows and !is_windows_drive_path) {
                         // UNC namespace -> file://server/share/path.ext
                         bun.strings.percentEncodeWrite(
-                            if (path.len > 2 and bun.path.isSepAny(path[0]) and bun.path.isSepAny(path[1]))
+                            if (path.len > 2 and path[0] == '/' and path[1] == '/')
                                 path[2..]
                             else
                                 path, // invalid but must not crash
@@ -4914,7 +4986,7 @@ pub fn IncrementalGraph(side: bake.Side) type {
         }
 
         fn newEdge(g: *@This(), edge: Edge) !EdgeIndex {
-            if (g.edges_free_list.popOrNull()) |index| {
+            if (g.edges_free_list.pop()) |index| {
                 g.edges.items[index.get()] = edge;
                 return index;
             }
@@ -5291,7 +5363,7 @@ const DirectoryWatchStore = struct {
     }
 
     fn appendDepAssumeCapacity(store: *DirectoryWatchStore, dep: Dep) Dep.Index {
-        if (store.dependencies_free_list.popOrNull()) |index| {
+        if (store.dependencies_free_list.pop()) |index| {
             store.dependencies.items[index.get()] = dep;
             return index;
         }
@@ -5639,6 +5711,7 @@ fn writeVisualizerMessage(dev: *DevServer, payload: *std.ArrayList(u8)) !void {
             0..,
         ) |k, v, i| {
             const normalized_key = dev.relativePath(k);
+            defer dev.releaseRelativePathBuf();
             try w.writeInt(u32, @intCast(normalized_key.len), .little);
             if (k.len == 0) continue;
             try w.writeAll(normalized_key);
@@ -5692,7 +5765,7 @@ pub fn onWebSocketUpgrade(
         .active_route = .none,
     });
     dev.active_websocket_connections.put(dev.allocator, dw, {}) catch bun.outOfMemory();
-    res.upgrade(
+    _ = res.upgrade(
         *HmrSocket,
         dw,
         req.header("sec-websocket-key") orelse "",
@@ -5704,12 +5777,13 @@ pub fn onWebSocketUpgrade(
 
 /// Every message is to use `.binary`/`ArrayBuffer` transport mode. The first byte
 /// indicates a Message ID; see comments on each type for how to interpret the rest.
+/// Avoid changing message ID values, as some of these are hard-coded in tests.
 ///
 /// This format is only intended for communication via the browser and DevServer.
 /// Server-side HMR is implemented using a different interface. This API is not
 /// versioned alongside Bun; breaking changes may occur at any point.
 ///
-/// All integers are sent in little-endian
+/// All integers are sent in little-endian.
 pub const MessageId = enum(u8) {
     /// Version payload. Sent on connection startup. The client should issue a
     /// hard-reload when it mismatches with its `config.version`.
@@ -5797,13 +5871,15 @@ pub const MessageId = enum(u8) {
     set_url_response = 'n',
     /// Used for synchronization in DevServer tests, to identify when a update was
     /// acknowledged by the watcher but intentionally took no action.
-    redundant_watch = 'r',
+    /// - `u8`: See bake-harness.ts WatchSynchronization enum.
+    testing_watch_synchronization = 'r',
 
     pub inline fn char(id: MessageId) u8 {
         return @intFromEnum(id);
     }
 };
 
+/// Avoid changing message ID values, as some of these are hard-coded in tests.
 pub const IncomingMessageId = enum(u8) {
     /// Subscribe to an event channel. Payload is a sequence of chars available
     /// in HmrTopic.
@@ -5811,6 +5887,8 @@ pub const IncomingMessageId = enum(u8) {
     /// Emitted on client-side navigations.
     /// Rest of payload is a UTF-8 string.
     set_url = 'n',
+    /// Tells the DevServer to batch events together.
+    testing_batch_events = 'H',
 
     /// Invalid data
     _,
@@ -5821,7 +5899,7 @@ const HmrTopic = enum(u8) {
     errors = 'e',
     browser_error = 'E',
     visualizer = 'v',
-    redundant_watch = 'r',
+    testing_watch_synchronization = 'r',
 
     /// Invalid data
     _,
@@ -5926,6 +6004,44 @@ const HmrSocket = struct {
                 var response: [5]u8 = .{MessageId.set_url_response.char()} ++ std.mem.toBytes(rbi.get());
                 _ = ws.send(&response, .binary, false, true);
             },
+            .testing_batch_events => switch (s.dev.testing_batch_events) {
+                .disabled => {
+                    if (s.dev.current_bundle != null) {
+                        s.dev.testing_batch_events = .enable_after_bundle;
+                    } else {
+                        s.dev.testing_batch_events = .{ .enabled = .empty };
+                        s.dev.publish(.testing_watch_synchronization, &.{
+                            MessageId.testing_watch_synchronization.char(),
+                            0,
+                        }, .binary);
+                    }
+                },
+                .enable_after_bundle => {
+                    // do not expose a websocket event that panics a release build
+                    bun.debugAssert(false);
+                    ws.close();
+                },
+                .enabled => |event_const| {
+                    var event = event_const;
+                    s.dev.testing_batch_events = .disabled;
+
+                    if (event.entry_points.set.count() == 0) {
+                        s.dev.publish(.testing_watch_synchronization, &.{
+                            MessageId.testing_watch_synchronization.char(),
+                            2,
+                        }, .binary);
+                        return;
+                    }
+
+                    s.dev.startAsyncBundle(
+                        event.entry_points,
+                        true,
+                        std.time.Timer.start() catch @panic("timers unsupported"),
+                    ) catch bun.outOfMemory();
+
+                    event.entry_points.deinit(s.dev.allocator);
+                },
+            },
             _ => ws.close(),
         }
     }
@@ -6183,7 +6299,10 @@ pub const HotReloadEvent = struct {
                     bun.fmt.fmtSlice(event.dirs.keys(), ", "),
                 });
 
-            dev.publish(.redundant_watch, &.{MessageId.redundant_watch.char()}, .binary);
+            dev.publish(.testing_watch_synchronization, &.{
+                MessageId.testing_watch_synchronization.char(),
+                1,
+            }, .binary);
             return;
         }
 
@@ -6202,6 +6321,7 @@ pub const HotReloadEvent = struct {
         defer debug.log("HMR Task end", .{});
 
         const dev = first.owner;
+
         if (Environment.isDebug) {
             assert(first.debug_mutex.tryLock());
             assert(first.contention_indicator.load(.seq_cst) == 0);
@@ -6214,7 +6334,7 @@ pub const HotReloadEvent = struct {
 
         var sfb = std.heap.stackFallback(4096, dev.allocator);
         const temp_alloc = sfb.get();
-        var entry_points: EntryPointList = EntryPointList.empty;
+        var entry_points: EntryPointList = .empty;
         defer entry_points.deinit(temp_alloc);
 
         first.processFileList(dev, &entry_points, temp_alloc);
@@ -6233,6 +6353,19 @@ pub const HotReloadEvent = struct {
             return;
         }
 
+        switch (dev.testing_batch_events) {
+            .disabled => {},
+            .enabled => |*ev| {
+                ev.append(dev, entry_points) catch bun.outOfMemory();
+                dev.publish(.testing_watch_synchronization, &.{
+                    MessageId.testing_watch_synchronization.char(),
+                    1,
+                }, .binary);
+                return;
+            },
+            .enable_after_bundle => bun.debugAssert(false),
+        }
+
         dev.startAsyncBundle(
             entry_points,
             true,
@@ -6514,6 +6647,8 @@ pub fn onRouterCollisionError(dev: *DevServer, rel_path: []const u8, other_id: O
         dev.relativePath(dev.server_graph.bundled_files.keys()[fromOpaqueFileId(.server, other_id).get()]),
     });
     Output.flush();
+
+    dev.releaseRelativePathBuf();
 }
 
 fn toOpaqueFileId(comptime side: bake.Side, index: IncrementalGraph(side).FileIndex) OpaqueFileId {
@@ -6537,7 +6672,9 @@ fn fromOpaqueFileId(comptime side: bake.Side, id: OpaqueFileId) IncrementalGraph
 }
 
 /// Returns posix style path, suitible for URLs and reproducible hashes.
-fn relativePath(dev: *const DevServer, path: []const u8) []const u8 {
+/// To avoid overwriting memory, this has a lock for the buffer.
+fn relativePath(dev: *DevServer, path: []const u8) []const u8 {
+    dev.relative_path_buf_lock.lock();
     bun.assert(dev.root[dev.root.len - 1] != '/');
 
     if (!std.fs.path.isAbsolute(path)) {
@@ -6550,15 +6687,20 @@ fn relativePath(dev: *const DevServer, path: []const u8) []const u8 {
     {
         return path[dev.root.len + 1 ..];
     }
-    const relative_path_buf = &struct {
-        threadlocal var buf: bun.PathBuffer = undefined;
-    }.buf;
-    const rel = bun.path.relativePlatformBuf(relative_path_buf, dev.root, path, .auto, true);
-    // @constCast: `rel` is owned by a mutable threadlocal buffer above
+
+    const rel = bun.path.relativePlatformBuf(&dev.relative_path_buf, dev.root, path, .auto, true);
+    // @constCast: `rel` is owned by a buffer on `dev`, which is mutable
     bun.path.platformToPosixInPlace(u8, @constCast(rel));
     return rel;
 }
 
+fn releaseRelativePathBuf(dev: *DevServer) void {
+    dev.relative_path_buf_lock.unlock();
+    if (bun.Environment.isDebug) {
+        dev.relative_path_buf = undefined;
+    }
+}
+
 fn dumpStateDueToCrash(dev: *DevServer) !void {
     comptime assert(bun.FeatureFlags.bake_debugging_features);
 
@@ -7190,6 +7332,7 @@ const ErrorReportRequest = struct {
                     const abs_path = result.file_paths[@intCast(index - 1)];
                     frame.source_url = .init(abs_path);
                     const rel_path = ctx.dev.relativePath(abs_path);
+                    defer ctx.dev.releaseRelativePathBuf();
                     if (bun.strings.eql(frame.function_name.value.ZigString.slice(), rel_path)) {
                         frame.function_name = .empty;
                     }
@@ -7279,6 +7422,7 @@ const ErrorReportRequest = struct {
             const src_to_write = frame.source_url.value.ZigString.slice();
             if (bun.strings.hasPrefixComptime(src_to_write, "/")) {
                 const file = ctx.dev.relativePath(src_to_write);
+                defer ctx.dev.releaseRelativePathBuf();
                 try w.writeInt(u32, @intCast(file.len), .little);
                 try w.writeAll(file);
             } else {
@@ -7413,6 +7557,19 @@ fn readString32(reader: anytype, alloc: Allocator) ![]const u8 {
     return memory;
 }
 
+const TestingBatch = struct {
+    entry_points: EntryPointList,
+
+    const empty: @This() = .{ .entry_points = .empty };
+
+    pub fn append(self: *@This(), dev: *DevServer, entry_points: EntryPointList) !void {
+        assert(entry_points.set.count() > 0);
+        for (entry_points.set.keys(), entry_points.set.values()) |k, v| {
+            try self.entry_points.append(dev.allocator, k, v);
+        }
+    }
+};
+
 /// userland implementation of https://github.com/ziglang/zig/issues/21879
 fn VoidFieldTypes(comptime T: type) type {
     const fields = @typeInfo(T).@"struct".fields;

src/bake/FrameworkRouter.zig

@@ -430,7 +430,7 @@ pub const Style = union(enum) {
             if (map.get(utf8.slice())) |style| {
                 return style;
             }
-        } else if (value.isCallable(global.vm())) {
+        } else if (value.isCallable()) {
             return .{ .javascript_defined = JSC.Strong.create(value, global) };
         }
 
@@ -810,7 +810,7 @@ fn newRoute(fr: *FrameworkRouter, alloc: Allocator, route_data: Route) !Route.In
 }
 
 fn newEdge(fr: *FrameworkRouter, alloc: Allocator, edge_data: Route.Edge) !Route.Edge.Index {
-    if (fr.freed_edges.popOrNull()) |i| {
+    if (fr.freed_edges.pop()) |i| {
         fr.edges.items[i.get()] = edge_data;
         return i;
     } else {

src/bake/bake.private.d.ts

@@ -26,6 +26,14 @@ interface Config {
   roots: FileIndex[];
 }
 
+declare namespace DEBUG {
+  /** 
+   * Set globally in debug builds.
+   * Removed using --drop=DEBUG.ASSERT in releases.
+   */
+  declare function ASSERT(condition: any, message?: string): asserts condition;
+}
+
 /** All modules for the initial bundle. */
 declare const unloadedModuleRegistry: Record<string, UnloadedModule>;
 declare type UnloadedModule = UnloadedESM | UnloadedCommonJS;
@@ -40,11 +48,12 @@ declare type EncodedDependencyArray = (string | number)[];
 declare type UnloadedCommonJS = (
   hmr: import("./hmr-module").HMRModule,
   module: import("./hmr-module").HMRModule["cjs"],
-) => any;
+  exports: unknown,
+) => unknown;
 declare type CommonJSModule = {
   id: Id;
   exports: any;
-  require: (id: Id) => any;
+  require: (id: Id) => unknown;
 };
 
 declare const config: Config;

src/bake/client/css-reloader.ts

@@ -180,7 +180,8 @@ export function editCssContent(id: string, newContent: string) {
     // Disable the link tag if it exists
     const linkSheet = entry.link?.sheet;
     if (linkSheet) linkSheet.disabled = true;
-    return;
+    return false;
   }
   sheet!.replace(newContent);
+  return !sheet!.disabled;
 }

src/bake/debug.ts

@@ -0,0 +1,14 @@
+if (IS_BUN_DEVELOPMENT) {
+  // After 1.2.6 is released, this can just be `ASSERT`
+  globalThis.DEBUG = {
+    ASSERT: function ASSERT(condition: any, message?: string): asserts condition {
+      if (!condition) {
+        if (typeof Bun === "undefined") {
+          console.assert(false, "ASSERTION FAILED" + (message ? `: ${message}` : ""));
+        } else {
+          console.error("ASSERTION FAILED" + (message ? `: ${message}` : ""));
+        }
+      }
+    },
+  };
+}

src/bake/hmr-module.ts

@@ -7,12 +7,12 @@
 // `require` on a module with transitive top-level await, or a missing export.
 // This was done to make incremental updates as isolated as possible.
 import {
-  __name,
+  __callDispose,
   __legacyDecorateClassTS,
   __legacyDecorateParamTS,
   __legacyMetadataTS,
+  __name,
   __using,
-  __callDispose,
 } from "../runtime.bun";
 
 /** List of loaded modules. Every `Id` gets one HMRModule, mutated across updates. */
@@ -58,6 +58,12 @@ interface HotAccept {
   single: boolean;
 }
 
+interface CJSModule {
+  id: Id;
+  exports: unknown;
+  require: (id: Id) => unknown;
+}
+
 /** Implementation details must remain in sync with js_parser.zig and bundle_v2.zig */
 export class HMRModule {
   /** Key in `registry` */
@@ -69,10 +75,10 @@ export class HMRModule {
   exports: any = null;
   /** For ESM, this is the converted CJS exports.
    *  For CJS, this is the `module` object. */
-  cjs: any;
+  cjs: CJSModule | any | null;
   /** When a module fails to load, trying to load it again
    *  should throw the same error */
-  failure: any = null;
+  failure: unknown = null;
   /** Two purposes:
    * 1. HMRModule[] - List of parsed imports. indexOf is used to go from HMRModule -> updater function
    * 2. any[] - List of module namespace objects. Read by the ESM module's load function.
@@ -129,27 +135,6 @@ export class HMRModule {
       : import(id);
   }
 
-  /**
-   * Files which only export functions (and have no other statements) are
-   * implicitly `import.meta.hot.accept`ed, however it is done in a special way
-   * where functions are proxied. This is special behavior to make stuff "just
-   * work".
-   */
-  implicitlyAccept(exports) {
-    if (IS_BUN_DEVELOPMENT) assert(this.esm);
-    this.selfAccept ??= implicitAcceptFunction;
-    const current = ((this.selfAccept as any).current ??= {});
-    if (IS_BUN_DEVELOPMENT) assert(typeof exports === "object");
-    const moduleExports = (this.exports = {});
-    for (const exportName in exports) {
-      const source = (current[exportName] = exports[exportName]);
-      if (IS_BUN_DEVELOPMENT) assert(typeof source === "function");
-      const proxied = (moduleExports[exportName] ??= proxyFn(current, exportName));
-      Object.defineProperty(proxied, "name", { value: source.name });
-      Object.defineProperty(proxied, "length", { value: source.length });
-    }
-  }
-
   reactRefreshAccept() {
     if (isReactRefreshBoundary(this.exports)) {
       this.accept();
@@ -297,15 +282,24 @@ export function loadModuleSync(id: Id, isUserDynamic: boolean, importer: HMRModu
     if (!mod) {
       mod = new HMRModule(id, true);
       registry.set(id, mod);
+    } else if (mod.esm) {
+      mod.esm = false;
+      mod.cjs = {
+        id,
+        exports: {},
+        require: mod.require.bind(this),
+      };
+      mod.exports = null;
     }
     if (importer) {
       mod.importers.add(importer);
     }
     try {
-      loadOrEsmModule(mod, mod.cjs);
+      const cjs = mod.cjs;
+      loadOrEsmModule(mod, cjs, cjs.exports);
     } catch (e) {
-      mod.state = State.Error;
-      mod.failure = e;
+      mod.state = State.Stale;
+      mod.cjs.exports = {};
       throw e;
     }
     mod.state = State.Loaded;
@@ -313,11 +307,11 @@ export function loadModuleSync(id: Id, isUserDynamic: boolean, importer: HMRModu
     // ESM
     if (IS_BUN_DEVELOPMENT) {
       try {
-        assert(Array.isArray(loadOrEsmModule[ESMProps.imports]));
-        assert(Array.isArray(loadOrEsmModule[ESMProps.exports]));
-        assert(Array.isArray(loadOrEsmModule[ESMProps.stars]));
-        assert(typeof loadOrEsmModule[ESMProps.load] === "function");
-        assert(typeof loadOrEsmModule[ESMProps.isAsync] === "boolean");
+        DEBUG.ASSERT(Array.isArray(loadOrEsmModule[ESMProps.imports]));
+        DEBUG.ASSERT(Array.isArray(loadOrEsmModule[ESMProps.exports]));
+        DEBUG.ASSERT(Array.isArray(loadOrEsmModule[ESMProps.stars]));
+        DEBUG.ASSERT(typeof loadOrEsmModule[ESMProps.load] === "function");
+        DEBUG.ASSERT(typeof loadOrEsmModule[ESMProps.isAsync] === "boolean");
       } catch (e) {
         console.warn(id, loadOrEsmModule);
         throw e;
@@ -330,6 +324,10 @@ export function loadModuleSync(id: Id, isUserDynamic: boolean, importer: HMRModu
     if (!mod) {
       mod = new HMRModule(id, false);
       registry.set(id, mod);
+    } else if (!mod.esm) {
+      mod.esm = true;
+      mod.cjs = null;
+      mod.exports = null;
     }
     if (importer) {
       mod.importers.add(importer);
@@ -384,29 +382,37 @@ export function loadModuleAsync<IsUserDynamic extends boolean>(
     if (!mod) {
       mod = new HMRModule(id, true);
       registry.set(id, mod);
+    } else if (mod.esm) {
+      mod.esm = false;
+      mod.cjs = {
+        id,
+        exports: {},
+        require: mod.require.bind(this),
+      };
+      mod.exports = null;
     }
     if (importer) {
       mod.importers.add(importer);
     }
     try {
-      loadOrEsmModule(mod, mod.cjs);
+      const cjs = mod.cjs;
+      loadOrEsmModule(mod, cjs, cjs.exports);
     } catch (e) {
-      mod.state = State.Error;
-      mod.failure = e;
+      mod.state = State.Stale;
+      mod.cjs.exports = {};
       throw e;
     }
     mod.state = State.Loaded;
-
     return mod;
   } else {
     // ESM
     if (IS_BUN_DEVELOPMENT) {
       try {
-        assert(Array.isArray(loadOrEsmModule[0]));
-        assert(Array.isArray(loadOrEsmModule[1]));
-        assert(Array.isArray(loadOrEsmModule[2]));
-        assert(typeof loadOrEsmModule[3] === "function");
-        assert(typeof loadOrEsmModule[4] === "boolean");
+        DEBUG.ASSERT(Array.isArray(loadOrEsmModule[0]));
+        DEBUG.ASSERT(Array.isArray(loadOrEsmModule[1]));
+        DEBUG.ASSERT(Array.isArray(loadOrEsmModule[2]));
+        DEBUG.ASSERT(typeof loadOrEsmModule[3] === "function");
+        DEBUG.ASSERT(typeof loadOrEsmModule[4] === "boolean");
       } catch (e) {
         console.warn(id, loadOrEsmModule);
         throw e;
@@ -417,19 +423,21 @@ export function loadModuleAsync<IsUserDynamic extends boolean>(
     if (!mod) {
       mod = new HMRModule(id, false);
       registry.set(id, mod);
+    } else if (!mod.esm) {
+      mod.esm = true;
+      mod.exports = null;
+      mod.cjs = null;
     }
     if (importer) {
       mod.importers.add(importer);
     }
 
     const { list, isAsync } = parseEsmDependencies(mod, deps, loadModuleAsync<false>);
-    if (IS_BUN_DEVELOPMENT) {
-      if (isAsync) {
-        assert(list.some(x => x instanceof Promise));
-      } else {
-        assert(list.every(x => x instanceof HMRModule));
-      }
-    }
+    DEBUG.ASSERT(
+      isAsync //
+        ? list.some(x => x instanceof Promise)
+        : list.every(x => x instanceof HMRModule)
+    );
 
     // Running finishLoadModuleAsync synchronously when there are no promises is
     // not a performance optimization but a behavioral correctness issue.
@@ -481,7 +489,7 @@ function finishLoadModuleAsync(mod: HMRModule, load: UnloadedESM[3], modules: HM
 type GenericModuleLoader<R> = (id: Id, isUserDynamic: false, importer: HMRModule) => R;
 // TODO: This function is currently recursive.
 function parseEsmDependencies<T extends GenericModuleLoader<any>>(
-  mod: HMRModule,
+  parent: HMRModule,
   deps: (string | number)[],
   enqueueModuleLoad: T,
 ) {
@@ -491,10 +499,11 @@ function parseEsmDependencies<T extends GenericModuleLoader<any>>(
   const { length } = deps;
   while (i < length) {
     const dep = deps[i] as string;
-    if (IS_BUN_DEVELOPMENT) assert(typeof dep === "string");
+    DEBUG.ASSERT(typeof dep === "string");
     let expectedExportKeyEnd = i + 2 + (deps[i + 1] as number);
-    if (IS_BUN_DEVELOPMENT) assert(typeof deps[i + 1] === "number");
-    list.push(enqueueModuleLoad(dep, false, mod));
+    DEBUG.ASSERT(typeof deps[i + 1] === "number");
+    const promiseOrModule = enqueueModuleLoad(dep, false, parent);
+    list.push(promiseOrModule);
 
     const unloadedModule = unloadedModuleRegistry[dep];
     if (!unloadedModule) {
@@ -505,18 +514,27 @@ function parseEsmDependencies<T extends GenericModuleLoader<any>>(
       i += 2;
       while (i < expectedExportKeyEnd) {
         const key = deps[i] as string;
-        if (IS_BUN_DEVELOPMENT) assert(typeof key === "string");
-        if (!availableExportKeys.includes(key)) {
-          if (!hasExportStar(unloadedModule[ESMProps.stars], key)) {
-            throw new SyntaxError(`Module "${dep}" does not export key "${key}"`);
-          }
-        }
+        DEBUG.ASSERT(typeof key === "string");
+        // TODO: there is a bug in the way exports are verified. Additionally a
+        // possible performance issue. For the meantime, this is disabled since
+        // it was not shipped in the initial 1.2.3 HMR, and real issues will 
+        // just throw 'undefined is not a function' or so on.
+
+        // if (!availableExportKeys.includes(key)) {
+        //   if (!hasExportStar(unloadedModule[ESMProps.stars], key)) {
+        //     throw new SyntaxError(`Module "${dep}" does not export key "${key}"`);
+        //   }
+        // }
         i++;
       }
-      isAsync ||= unloadedModule[ESMProps.isAsync];
+      isAsync ||= promiseOrModule instanceof Promise;
     } else {
-      if (IS_BUN_DEVELOPMENT) assert(!registry.get(dep)?.esm);
+      DEBUG.ASSERT(!registry.get(dep)?.esm);
       i = expectedExportKeyEnd;
+
+      if (IS_BUN_DEVELOPMENT) {
+        DEBUG.ASSERT(list[list.length - 1] as any instanceof HMRModule);
+      }
     }
   }
   return { list, isAsync };
@@ -531,7 +549,7 @@ function hasExportStar(starImports: Id[], key: string) {
     if (visited.has(starImport)) continue;
     visited.add(starImport);
     const mod = unloadedModuleRegistry[starImport];
-    if (IS_BUN_DEVELOPMENT) assert(mod, `Module "${starImport}" not found`);
+    DEBUG.ASSERT(mod, `Module "${starImport}" not found`);
     if (typeof mod === "function") {
       return true;
     }
@@ -558,7 +576,11 @@ type HotAcceptFunction = (esmExports?: any | void) => void;
 type HotArrayAcceptFunction = (esmExports: (any | void)[]) => void;
 type HotDisposeFunction = (data: any) => void | Promise<void>;
 type HotEventHandler = (data: any) => void;
-type HMREvent =
+
+// If updating this, make sure the `devserver.d.ts` types are
+// kept in sync.
+type HMREvent = 
+  | "bun:ready"
   | "bun:beforeUpdate"
   | "bun:afterUpdate"
   | "bun:beforeFullReload"
@@ -648,11 +670,9 @@ export async function replaceModules(modules: Record<Id, UnloadedModule>) {
     for (const boundary of failures) {
       const path: Id[] = [];
       let current = registry.get(boundary)!;
-      if (IS_BUN_DEVELOPMENT) {
-        assert(!boundary.endsWith(".html")); // caller should have already reloaded
-        assert(current);
-        assert(current.selfAccept === null);
-      }
+        DEBUG.ASSERT(!boundary.endsWith(".html")); // caller should have already reloaded
+        DEBUG.ASSERT(current);
+        DEBUG.ASSERT(current.selfAccept === null);
       if (current.importers.size === 0) {
         message += `Module "${boundary}" is a root module that does not self-accept.\n`;
         continue;
@@ -665,13 +685,11 @@ export async function replaceModules(modules: Record<Id, UnloadedModule>) {
           current = importer;
           continue outer;
         }
-        if (IS_BUN_DEVELOPMENT) assert(false);
+        DEBUG.ASSERT(false);
         break;
       }
       path.push(current.id);
-      if (IS_BUN_DEVELOPMENT) {
-        assert(path.length > 0);
-      }
+      DEBUG.ASSERT(path.length > 0);
       message += `Module "${boundary}" is not accepted by ${path[1]}${path.length > 1 ? "," : "."}\n`;
       for (let i = 2, len = path.length; i < len; i++) {
         const isLast = i === len - 1;
@@ -725,7 +743,7 @@ export async function replaceModules(modules: Record<Id, UnloadedModule>) {
         selfAccept(getEsmExports(mod));
       }
     } else {
-      if (IS_BUN_DEVELOPMENT) assert(modOrPromise instanceof Promise);
+      DEBUG.ASSERT(modOrPromise instanceof Promise);
       promises.push(
         (modOrPromise as Promise<HMRModule>).then(mod => {
           if (selfAccept) {
@@ -773,7 +791,7 @@ function createAcceptArray(modules: string[], key: Id) {
   const arr = new Array(modules.length);
   arr.fill(undefined);
   const i = modules.indexOf(key);
-  if (IS_BUN_DEVELOPMENT) assert(i !== -1);
+  DEBUG.ASSERT(i !== -1);
   arr[i] = getEsmExports(registry.get(key)!);
   return arr;
 }
@@ -849,12 +867,6 @@ function registerSynthetic(id: Id, esmExports) {
   registry.set(id, module);
 }
 
-function assert(condition: any, message?: string): asserts condition {
-  if (!condition) {
-    console.assert(false, "ASSERTION FAILED" + (message ? `: ${message}` : ""));
-  }
-}
-
 export function setRefreshRuntime(runtime: HMRModule) {
   refreshRuntime = getEsmExports(runtime);
 
@@ -899,14 +911,6 @@ function isReactRefreshBoundary(esmExports): boolean {
 
 function implicitAcceptFunction() {}
 
-const apply = Function.prototype.apply;
-function proxyFn(target: any, key: string) {
-  const f = function () {
-    return apply.call(target[key], this, arguments);
-  };
-  return f;
-}
-
 declare global {
   interface Error {
     asyncId?: string;
@@ -937,3 +941,13 @@ if (side === "client") {
     onServerSideReload: cb => (onServerSideReload = cb),
   });
 }
+
+// The following API may be altered at any point.
+// Thankfully, you can just call `import.meta.hot.on`
+let testingHook = globalThis['bun do not use this outside of internal testing or else i\'ll cry'];
+testingHook?.({
+  onEvent(event: HMREvent, cb) {
+    eventHandlers[event] ??= [];
+    eventHandlers[event]!.push(cb);
+  },
+});

src/bake/hmr-runtime-client.ts

@@ -1,5 +1,6 @@
 // This file is the entrypoint to the hot-module-reloading runtime
 // In the browser, this uses a WebSocket to communicate with the bundler.
+import './debug';
 import {
   loadModuleAsync,
   replaceModules,
@@ -153,8 +154,12 @@ const handlers = {
           onRuntimeError(e, true, false);
           return;
         }
+        emitEvent("bun:error", e);
         throw e;
       }
+    } else {
+      // Needed for testing.
+      emitEvent("bun:afterUpdate", null);
     }
   },
   [MessageId.set_url_response](view) {
@@ -216,6 +221,8 @@ try {
   }
 
   await loadModuleAsync(config.main, false, null);
+
+  emitEvent("bun:ready", null);
 } catch (e) {
   console.error(e);
   onRuntimeError(e, true, false);