diff --git a/src/repl.zig b/src/repl.zig
index 75697f307d..f00a842759 100644
--- a/src/repl.zig
+++ b/src/repl.zig
@@ -682,7 +682,7 @@ terminal_height: u16 = 24,
 ctrl_c_pressed: bool = false,
 
 // Buffered stdin
-stdin_buf: [256]u8 = undefined,
+stdin_buf: [256]u8 = .{0} ** 256,
 stdin_buf_start: usize = 0,
 stdin_buf_end: usize = 0,
 
diff --git a/test/js/bun/repl/repl.test.ts b/test/js/bun/repl/repl.test.ts
index f9ae15829f..d798cd4416 100644
--- a/test/js/bun/repl/repl.test.ts
+++ b/test/js/bun/repl/repl.test.ts
@@ -134,7 +134,7 @@ async function withTerminalRepl(
   if (!proc.killed) proc.kill();
 }
 
-describe.todoIf(isWindows)("Bun REPL", () => {
+describe("Bun REPL", () => {
   describe("basic evaluation", () => {
     test("evaluates simple expression", async () => {
       const { stdout, exitCode } = await runRepl(["1 + 1", ".exit"]);