diff --git a/src/secrets/run.ts b/src/secrets/run.ts
index cf4f62d..1acac94 100644
--- a/src/secrets/run.ts
+++ b/src/secrets/run.ts
@@ -45,6 +45,7 @@ export async function runSecret(
           let total = 0;
           let failure: SecretCode | undefined;
           let killTimer: ReturnType<typeof setTimeout> | undefined;
+          let stopRequested = false;
           const child = spawn(executor.executable, [executor.entry], {
             cwd: executor.cwd,
             shell: false,
@@ -62,12 +63,17 @@ export async function runSecret(
               try {
                 process.kill(-child.pid, sig);
               } catch (error) {
-                if ((error as NodeJS.ErrnoException).code !== 'ESRCH')
-                  failure = 'EXECUTOR_FAILED';
+                const errno = (error as NodeJS.ErrnoException).code;
+                // macOS reports EPERM for a group whose leader exited but is not yet reaped.
+                const gone =
+                  errno === 'ESRCH' ||
+                  (errno === 'EPERM' && (stopRequested || done));
+                if (!gone) failure ??= 'EXECUTOR_FAILED';
               }
           };
           const stop = (why: SecretCode) => {
-            if (done) return;
+            if (done || stopRequested) return;
+            stopRequested = true;
             failure ??= why;
             child.stdin.destroy();
             kill('SIGTERM');
diff --git a/tests/secrets.test.ts b/tests/secrets.test.ts
index 7a601a4..5f35057 100644
--- a/tests/secrets.test.ts
+++ b/tests/secrets.test.ts
@@ -505,6 +505,27 @@ describe.skipIf(process.platform !== 'darwin')(
         });
       },
     );
+    it('keeps the stop reason when a later group signal reports EPERM', async () => {
+      await writeFile(
+        path.join(root, 'package/main.cjs'),
+        "process.stdout.write('x'.repeat(100000));setInterval(()=>{},1000)",
+      );
+      await setup();
+      const kill = process.kill.bind(process);
+      let groupSignals = 0;
+      // macOS returns EPERM when signalling a group whose leader exited but is not yet reaped.
+      vi.spyOn(process, 'kill').mockImplementation((pid, signal) => {
+        if (typeof pid === 'number' && pid < 0 && ++groupSignals > 1) {
+          throw Object.assign(new Error('kill EPERM'), { code: 'EPERM' });
+        }
+        return kill(pid, signal);
+      });
+      expect(await run()).toMatchObject({
+        status: 'outcome_unknown',
+        code: 'OUTPUT_LIMIT',
+      });
+      expect(groupSignals).toBeGreaterThan(1);
+    });
     it('honors cancellation before decrypting', async () => {
       await setup();
       const c = new AbortController();