diff --git a/.changeset/ci-broken-pipe-worker-crash.md b/.changeset/ci-broken-pipe-worker-crash.md
new file mode 100644
index 0000000..1b3e533
--- /dev/null
+++ b/.changeset/ci-broken-pipe-worker-crash.md
@@ -0,0 +1,8 @@
+---
+'@offckb/cli': patch
+---
+
+Fix two CI failures on the macOS/Windows test matrix:
+
+- The broken-pipe regression test no longer crashes the jest worker ("jest worker process crashed for an unknown reason: exitCode=0"). It captures the EPIPE handlers installed by `installBrokenPipeHandlers` through a spy on `stream.on` instead of binding them to the live process stdout/stderr streams, so a real stream error can no longer reach a handler with the real (unmocked) `process.exit` and terminate the worker. The covered policy is unchanged: EPIPE exits 0 during normal operation, is swallowed during a graceful shutdown, and non-EPIPE errors are rethrown.
+- The Windows daemon-identity probe no longer times out during the `verifyDaemonIdentity` test. The PowerShell + CIM query needs a cold start of a second or two, which routinely exceeded the old 5s probe bound on a loaded runner, making the identity check fail closed against a live process it should have accepted. The probe timeout is now 15s — generous enough for a slow machine, still bounded so a genuinely hung probe fails closed.
diff --git a/src/util/daemon.ts b/src/util/daemon.ts
index d454177..bfaa55f 100644
--- a/src/util/daemon.ts
+++ b/src/util/daemon.ts
@@ -296,9 +296,14 @@ function parsePsLstart(text: string): number | null {
   return Number.isFinite(ms) ? ms : null;
 }
 
+// Generous so the Windows daemon-identity probe (PowerShell + CIM cold start)
+// does not fail closed against a legitimate daemon on a slow machine; it only
+// needs to bound a genuinely hung probe.
+const PROCESS_PROBE_TIMEOUT_MS = 15_000;
+
 function execFileText(command: string, args: string[]): Promise<string | null> {
   return new Promise((resolve) => {
-    execFile(command, args, { timeout: 5000 }, (error, stdout) => {
+    execFile(command, args, { timeout: PROCESS_PROBE_TIMEOUT_MS }, (error, stdout) => {
       if (error) {
         resolve(null);
         return;
diff --git a/tests/broken-pipe.test.ts b/tests/broken-pipe.test.ts
index 22be314..3ddfdac 100644
--- a/tests/broken-pipe.test.ts
+++ b/tests/broken-pipe.test.ts
@@ -25,66 +25,86 @@ function epipe(): NodeJS.ErrnoException {
 describe('util/shutdown broken-pipe policy', () => {
   let shutdown: ShutdownModule;
   let exitSpy: jest.SpyInstance<never, [code?: number]>;
-  let stdoutListeners: unknown[];
-  let stderrListeners: unknown[];
 
   beforeEach(() => {
     jest.resetModules();
     shutdown = require('../src/util/shutdown') as ShutdownModule;
-    stdoutListeners = process.stdout.rawListeners('error');
-    stderrListeners = process.stderr.rawListeners('error');
-    exitSpy = jest
-      .spyOn(process, 'exit')
-      .mockImplementation(((code?: number) => {
-        throw new ProcessExit(code);
-      }) as (code?: number) => never);
+    exitSpy = jest.spyOn(process, 'exit').mockImplementation(((code?: number) => {
+      throw new ProcessExit(code);
+    }) as (code?: number) => never);
   });
 
   afterEach(() => {
     exitSpy.mockRestore();
-    for (const [stream, original] of [
-      [process.stdout, stdoutListeners],
-      [process.stderr, stderrListeners],
-    ] as const) {
-      for (const listener of stream.rawListeners('error')) {
-        if (!original.includes(listener)) {
-          stream.removeListener('error', listener as (error: Error) => void);
+  });
+
+  /**
+   * Run installBrokenPipeHandlers without binding anything to the live
+   * process.stdout/stderr streams. Installing error handlers on the real
+   * streams inside a shared jest worker is unsafe: a genuine stream error
+   * (EPIPE on a closed pipe while running with piped output on macOS/Windows)
+   * can fire asynchronously and reach the handler after the mocked
+   * process.exit has been restored, causing the worker itself to exit — the
+   * "jest worker process crashed for an unknown reason: exitCode=0" CI
+   * failure. Capturing the handlers through a spy on `stream.on` tests the
+   * exact same policy logic (including that both streams get a handler) with
+   * no global side effects.
+   */
+  function captureHandlers(): Array<(error: NodeJS.ErrnoException) => void> {
+    const handlers: Array<(error: NodeJS.ErrnoException) => void> = [];
+    // jest.spyOn calls through to the original method by default, so a plain
+    // spy would still register the handlers on the live streams (and
+    // mockRestore does not remove them). mockReturnThis makes `.on()` a no-op
+    // that only records the call, keeping the streams untouched.
+    const stdoutOn = jest.spyOn(process.stdout, 'on').mockReturnThis();
+    const stderrOn = jest.spyOn(process.stderr, 'on').mockReturnThis();
+    shutdown.installBrokenPipeHandlers();
+    for (const streamOn of [stdoutOn, stderrOn]) {
+      for (const [event, handler] of streamOn.mock.calls) {
+        if (event === 'error') {
+          handlers.push(handler as (error: NodeJS.ErrnoException) => void);
         }
       }
+      streamOn.mockRestore();
     }
-  });
+    return handlers;
+  }
 
   it('starts outside a graceful shutdown', () => {
     expect(shutdown.isGracefulShutdownInProgress()).toBe(false);
   });
 
+  it('installs an error handler on both stdout and stderr', () => {
+    expect(captureHandlers()).toHaveLength(2);
+  });
+
   it('exits 0 on EPIPE during normal operation (the `| head` case)', () => {
-    shutdown.installBrokenPipeHandlers();
-    expect(() => process.stdout.emit('error', epipe())).toThrow(ProcessExit);
+    const [stdoutHandler] = captureHandlers();
+    expect(() => stdoutHandler(epipe())).toThrow(ProcessExit);
     expect(exitSpy).toHaveBeenCalledWith(0);
   });
 
   it('handles stderr the same way as stdout', () => {
-    shutdown.installBrokenPipeHandlers();
-    expect(() => process.stderr.emit('error', epipe())).toThrow(ProcessExit);
+    const [, stderrHandler] = captureHandlers();
+    expect(() => stderrHandler(epipe())).toThrow(ProcessExit);
     expect(exitSpy).toHaveBeenCalledWith(0);
   });
 
   it('swallows EPIPE once a graceful shutdown is in progress', () => {
-    shutdown.installBrokenPipeHandlers();
+    const [stdoutHandler, stderrHandler] = captureHandlers();
     shutdown.enterGracefulShutdown();
     expect(shutdown.isGracefulShutdownInProgress()).toBe(true);
     // Repeated writes to the dead pipe keep erroring; none may exit.
-    expect(() => process.stdout.emit('error', epipe())).not.toThrow();
-    expect(() => process.stderr.emit('error', epipe())).not.toThrow();
+    expect(() => stdoutHandler(epipe())).not.toThrow();
+    expect(() => stderrHandler(epipe())).not.toThrow();
     expect(exitSpy).not.toHaveBeenCalled();
   });
 
   it('still rethrows non-EPIPE stream errors during a shutdown', () => {
-    shutdown.installBrokenPipeHandlers();
+    const [stdoutHandler] = captureHandlers();
     shutdown.enterGracefulShutdown();
     const error = new Error('some other stream failure');
-    expect(() => process.stdout.emit('error', error)).toThrow(error);
+    expect(() => stdoutHandler(error)).toThrow(error);
     expect(exitSpy).not.toHaveBeenCalled();
   });
 });