diff --git a/packages/alchemy/src/Test/Vitest.ts b/packages/alchemy/src/Test/Vitest.ts
index 9a509bec13..71235ac4de 100644
--- a/packages/alchemy/src/Test/Vitest.ts
+++ b/packages/alchemy/src/Test/Vitest.ts
@@ -6,6 +6,7 @@ import * as Scope from "effect/Scope";
 import {
   afterAll as vitestAfterAll,
   afterEach as vitestAfterEach,
+  aroundAll as vitestAroundAll,
   beforeAll as vitestBeforeAll,
   beforeEach as vitestBeforeEach,
 } from "vitest";
@@ -227,18 +228,19 @@ export const make = <ROut = any>(options: MakeOptions<ROut>): TestApi => {
 
   // Fallback cleanup: if the user never calls `destroy(Stack)` (e.g.
   // `NO_DESTROY=1`), nothing else closes the shared scope and the sidecar
-  // child process leaks past the test process. Register an `afterAll` that
-  // closes it (and the RPC sidecar, which lives in its own scope so that
-  // mid-file `destroy(Stack)` calls can't kill it for later tests). We defer
-  // registration to a microtask so it runs AFTER any user-registered
-  // `afterAll` (including `destroy(Stack)`); vitest runs afterAll hooks in
-  // registration order.
+  // child process leaks past the test process. `aroundAll` owns the complete
+  // suite lifecycle, so cleanup runs after suite hooks and their cleanups even
+  // when setup, a test, or teardown fails. Hook ordering does not affect it.
   const closeAll = sidecar
     ? Effect.andThen(closeScope, sidecar.close)
     : closeScope;
-  queueMicrotask(() => {
-    vitestAfterAll(() => Effect.runPromise(closeAll), DEFAULT_TIMEOUT);
-  });
+  vitestAroundAll(async (runSuite) => {
+    try {
+      await runSuite();
+    } finally {
+      await Effect.runPromise(closeAll);
+    }
+  }, DEFAULT_TIMEOUT);
 
   return {
     test,
diff --git a/packages/alchemy/test/Test/Vitest.test.ts b/packages/alchemy/test/Test/Vitest.test.ts
new file mode 100644
index 0000000000..2579873d8d
--- /dev/null
+++ b/packages/alchemy/test/Test/Vitest.test.ts
@@ -0,0 +1,90 @@
+import { PlatformServices } from "@/Util/PlatformServices.ts";
+import { exec } from "@/Util/exec.ts";
+import { describe, expect, test } from "alchemy-test";
+import * as Effect from "effect/Effect";
+import * as ChildProcess from "effect/unstable/process/ChildProcess";
+import { fileURLToPath } from "node:url";
+
+const fixturesDirectory = new URL("./fixtures/", import.meta.url);
+const configPath = fileURLToPath(
+  new URL("vitest-cleanup-order.config.ts", fixturesDirectory),
+);
+
+const runVitestFixture = (
+  fixtureName: string,
+  hooks: "stack" | "list" = "stack",
+) =>
+  exec(
+    ChildProcess.make(
+      "pnpm",
+      [
+        "exec",
+        "vitest",
+        "run",
+        fileURLToPath(new URL(fixtureName, fixturesDirectory)),
+        "--config",
+        configPath,
+        `--sequence.hooks=${hooks}`,
+        "--reporter=verbose",
+      ],
+      { shell: false },
+    ),
+  ).pipe(Effect.scoped);
+
+const processOutput = (result: {
+  readonly stdout: string;
+  readonly stderr: string;
+}) => `${result.stdout}\n${result.stderr}`;
+
+describe("Vitest fallback cleanup", () => {
+  test.live(
+    "runs after user afterAll hooks for stack and list ordering",
+    () =>
+      Effect.gen(function* () {
+        for (const hooks of ["stack", "list"] as const) {
+          const result = yield* runVitestFixture(
+            "vitest-cleanup-order.fixture.ts",
+            hooks,
+          );
+
+          expect(result.exitCode).toBe(0);
+          expect(processOutput(result)).toContain(
+            "VITEST_CLEANUP_ORDER:user afterAll,alchemy fallback cleanup",
+          );
+        }
+      }).pipe(Effect.provide(PlatformServices)),
+    { timeout: 30_000 },
+  );
+
+  test.live(
+    "runs when a later beforeAll hook fails",
+    () =>
+      Effect.gen(function* () {
+        const result = yield* runVitestFixture(
+          "vitest-cleanup-after-failed-before-all.fixture.ts",
+        );
+        const output = processOutput(result);
+
+        expect(result.exitCode).toBe(1);
+        expect(output).toContain("EXPECTED_BEFORE_ALL_FAILURE");
+        expect(output).toContain("VITEST_CLEANUP_AFTER_FAILED_BEFORE_ALL");
+      }).pipe(Effect.provide(PlatformServices)),
+    { timeout: 30_000 },
+  );
+
+  test.live(
+    "runs when an afterAll hook fails",
+    () =>
+      Effect.gen(function* () {
+        const result = yield* runVitestFixture(
+          "vitest-cleanup-after-failed-after-all.fixture.ts",
+        );
+        const output = processOutput(result);
+
+        expect(result.exitCode).toBe(1);
+        expect(output).toContain("EXPECTED_AFTER_ALL_FAILURE");
+        expect(output).toContain("VITEST_CLEANUP_AFTER_FAILED_AFTER_ALL");
+      }).pipe(Effect.provide(PlatformServices)),
+    { timeout: 30_000 },
+  );
+});
diff --git a/packages/alchemy/test/Test/fixtures/vitest-cleanup-after-failed-after-all.fixture.ts b/packages/alchemy/test/Test/fixtures/vitest-cleanup-after-failed-after-all.fixture.ts
new file mode 100644
index 0000000000..0e3924375e
--- /dev/null
+++ b/packages/alchemy/test/Test/fixtures/vitest-cleanup-after-failed-after-all.fixture.ts
@@ -0,0 +1,20 @@
+import * as Effect from "effect/Effect";
+import * as Layer from "effect/Layer";
+import { afterAll } from "vitest";
+import * as Test from "alchemy/Test/Vitest";
+
+const testApi = Test.make({ providers: Layer.empty, dev: false });
+
+testApi.beforeAll(
+  Effect.addFinalizer(() =>
+    Effect.sync(() => {
+      console.log("VITEST_CLEANUP_AFTER_FAILED_AFTER_ALL");
+    }),
+  ),
+);
+
+testApi.test("runs before afterAll fails", Effect.void);
+
+afterAll(() => {
+  throw new Error("EXPECTED_AFTER_ALL_FAILURE");
+});
diff --git a/packages/alchemy/test/Test/fixtures/vitest-cleanup-after-failed-before-all.fixture.ts b/packages/alchemy/test/Test/fixtures/vitest-cleanup-after-failed-before-all.fixture.ts
new file mode 100644
index 0000000000..575ce998c0
--- /dev/null
+++ b/packages/alchemy/test/Test/fixtures/vitest-cleanup-after-failed-before-all.fixture.ts
@@ -0,0 +1,20 @@
+import * as Effect from "effect/Effect";
+import * as Layer from "effect/Layer";
+import { beforeAll } from "vitest";
+import * as Test from "alchemy/Test/Vitest";
+
+const testApi = Test.make({ providers: Layer.empty, dev: false });
+
+testApi.beforeAll(
+  Effect.addFinalizer(() =>
+    Effect.sync(() => {
+      console.log("VITEST_CLEANUP_AFTER_FAILED_BEFORE_ALL");
+    }),
+  ),
+);
+
+beforeAll(() => {
+  throw new Error("EXPECTED_BEFORE_ALL_FAILURE");
+});
+
+testApi.test("is skipped after beforeAll fails", Effect.void);
diff --git a/packages/alchemy/test/Test/fixtures/vitest-cleanup-order.config.ts b/packages/alchemy/test/Test/fixtures/vitest-cleanup-order.config.ts
new file mode 100644
index 0000000000..05679b0704
--- /dev/null
+++ b/packages/alchemy/test/Test/fixtures/vitest-cleanup-order.config.ts
@@ -0,0 +1,16 @@
+import { fileURLToPath } from "node:url";
+import { defineConfig } from "vitest/config";
+
+export default defineConfig({
+  resolve: {
+    alias: {
+      "alchemy/Test/Vitest": fileURLToPath(
+        new URL("../../../src/Test/Vitest.ts", import.meta.url),
+      ),
+    },
+  },
+  test: {
+    include: ["**/*.fixture.ts"],
+    sequence: { hooks: "stack" },
+  },
+});
diff --git a/packages/alchemy/test/Test/fixtures/vitest-cleanup-order.fixture.ts b/packages/alchemy/test/Test/fixtures/vitest-cleanup-order.fixture.ts
new file mode 100644
index 0000000000..aff398e275
--- /dev/null
+++ b/packages/alchemy/test/Test/fixtures/vitest-cleanup-order.fixture.ts
@@ -0,0 +1,26 @@
+import * as Effect from "effect/Effect";
+import * as Layer from "effect/Layer";
+import { afterAll, expect } from "vitest";
+import * as Test from "alchemy/Test/Vitest";
+
+const lifecycleEvents: string[] = [];
+const testApi = Test.make({ providers: Layer.empty, dev: false });
+
+const reportLifecycleEvents = () =>
+  console.log(`VITEST_CLEANUP_ORDER:${lifecycleEvents.join(",")}`);
+
+testApi.beforeAll(
+  Effect.addFinalizer(() =>
+    Effect.sync(() => {
+      lifecycleEvents.push("alchemy fallback cleanup");
+      reportLifecycleEvents();
+    }),
+  ),
+);
+
+testApi.test("runs a test before cleanup", Effect.void);
+
+afterAll(() => {
+  expect(lifecycleEvents).toEqual([]);
+  lifecycleEvents.push("user afterAll");
+});