From e5cd034e9ad82bf8335178fe73c930a191af443e Mon Sep 17 00:00:00 2001
From: Alistair Smith <alistair@anthropic.com>
Date: Thu, 5 Feb 2026 06:41:25 -0800
Subject: [PATCH] Define seed in crc32 types (#26754)

### What does this PR do?

Fixes #26711

### How did you verify your code works?

bun-types.test.ts integration test
---
 packages/bun-types/bun.d.ts                   | 2 +-
 test/integration/bun-types/fixture/hashing.ts | 6 ++++++
 2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/packages/bun-types/bun.d.ts b/packages/bun-types/bun.d.ts
index 418dbc87c9..5b34265536 100644
--- a/packages/bun-types/bun.d.ts
+++ b/packages/bun-types/bun.d.ts
@@ -2154,7 +2154,7 @@ declare module "bun" {
   interface Hash {
     wyhash: (data: string | ArrayBufferView | ArrayBuffer | SharedArrayBuffer, seed?: bigint) => bigint;
     adler32: (data: string | ArrayBufferView | ArrayBuffer | SharedArrayBuffer) => number;
-    crc32: (data: string | ArrayBufferView | ArrayBuffer | SharedArrayBuffer) => number;
+    crc32: (data: string | ArrayBufferView | ArrayBuffer | SharedArrayBuffer, seed?: number) => number;
     cityHash32: (data: string | ArrayBufferView | ArrayBuffer | SharedArrayBuffer) => number;
     cityHash64: (data: string | ArrayBufferView | ArrayBuffer | SharedArrayBuffer, seed?: bigint) => bigint;
     xxHash32: (data: string | ArrayBufferView | ArrayBuffer | SharedArrayBuffer, seed?: number) => number;
diff --git a/test/integration/bun-types/fixture/hashing.ts b/test/integration/bun-types/fixture/hashing.ts
index 553e0f1ff0..db937b2f20 100644
--- a/test/integration/bun-types/fixture/hashing.ts
+++ b/test/integration/bun-types/fixture/hashing.ts
@@ -1 +1,7 @@
 Bun.hash.wyhash("asdf", 1234n);
+
+// https://github.com/oven-sh/bun/issues/26043
+// Bun.hash.crc32 accepts optional seed parameter for incremental CRC32 computation
+let crc = 0;
+crc = Bun.hash.crc32(new Uint8Array([1, 2, 3]), crc);
+crc = Bun.hash.crc32(new Uint8Array([4, 5, 6]), crc);