diff --git a/.github/workflows/test-node.yml b/.github/workflows/test-node.yml
new file mode 100644
index 0000000..247b408
--- /dev/null
+++ b/.github/workflows/test-node.yml
@@ -0,0 +1,24 @@
+name: Test (Node)
+
+on:
+  push:
+    branches:
+      - main
+  pull_request:
+  workflow_dispatch:
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: actions/setup-node@v4
+        with:
+          node-version: 22.x
+      - name: Install deps
+        run: |
+          npx jsr install
+      - name: Test
+        run: |
+          npx --yes tsx --test *_test.ts
+        timeout-minutes: 5
diff --git a/.gitignore b/.gitignore
index f1eb3c6..1973f0f 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,3 +1,4 @@
 /npm
 deno.lock
 .coverage
+node_modules
diff --git a/.npmrc b/.npmrc
new file mode 100644
index 0000000..41583e3
--- /dev/null
+++ b/.npmrc
@@ -0,0 +1 @@
+@jsr:registry=https://npm.jsr.io
diff --git a/deno.jsonc b/deno.jsonc
index e45bcbb..27fab66 100644
--- a/deno.jsonc
+++ b/deno.jsonc
@@ -25,7 +25,6 @@
     ]
   },
   "imports": {
-    "@core/unknownutil": "jsr:@core/unknownutil@^4.0.0",
     "@core/errorutil": "./mod.ts",
     "@core/errorutil/error-object": "./error_object.ts",
     "@core/errorutil/raise": "./raise.ts",
@@ -33,6 +32,8 @@
     "@core/errorutil/try-or-else": "./try_or_else.ts",
     "@core/errorutil/unimplemented": "./unimplemented.ts",
     "@core/errorutil/unreachable": "./unreachable.ts",
+    "@core/unknownutil": "jsr:@core/unknownutil@^4.0.0",
+    "@cross/test": "jsr:@cross/test@^0.0.9",
     "@std/assert": "jsr:@std/assert@^1.0.0"
   },
   "tasks": {
diff --git a/error_object_test.ts b/error_object_test.ts
index 34404f7..2939e81 100644
--- a/error_object_test.ts
+++ b/error_object_test.ts
@@ -1,3 +1,4 @@
+import { test } from "@cross/test";
 import { assertEquals, assertInstanceOf } from "@std/assert";
 import { fromErrorObject, toErrorObject } from "./error_object.ts";
 
@@ -12,57 +13,53 @@ class CustomError extends Error {
   }
 }
 
-Deno.test("toErrorObject", async (t) => {
-  await t.step("Error", () => {
-    const err = new Error("error");
-    err.stack = "stack...";
-    const obj = toErrorObject(err);
-    assertEquals(obj, {
-      proto: "Error",
-      name: "Error",
-      message: "error",
-      stack: "stack...",
-      attributes: {},
-    });
+await test("toErrorObject with Error", () => {
+  const err = new Error("error");
+  err.stack = "stack...";
+  const obj = toErrorObject(err);
+  assertEquals(obj, {
+    proto: "Error",
+    name: "Error",
+    message: "error",
+    stack: "stack...",
+    attributes: {},
   });
+});
 
-  await t.step("CustomError", () => {
-    const err = new CustomError("error", "foo", 10);
-    err.stack = "stack...";
-    const obj = toErrorObject(err);
-    assertEquals(obj, {
-      proto: "CustomError",
-      name: "ThisIsCustomError",
-      message: "error",
-      stack: "stack...",
-      attributes: {
-        foo: "foo",
-        bar: 10,
-      },
-    });
+await test("toErrorObject with CustomError", () => {
+  const err = new CustomError("error", "foo", 10);
+  err.stack = "stack...";
+  const obj = toErrorObject(err);
+  assertEquals(obj, {
+    proto: "CustomError",
+    name: "ThisIsCustomError",
+    message: "error",
+    stack: "stack...",
+    attributes: {
+      foo: "foo",
+      bar: 10,
+    },
   });
 });
 
-Deno.test("fromErrorObject", async (t) => {
-  await t.step("Error", () => {
-    const obj = toErrorObject(new Error("error"));
-    obj.stack = "stack...";
-    const err = fromErrorObject(obj);
-    assertInstanceOf(err, Error);
-    assertEquals(err.name, "Error");
-    assertEquals(err.message, "error");
-    assertEquals(err.stack, "stack...");
-  });
+await test("fromErrorObject with Error", () => {
+  const obj = toErrorObject(new Error("error"));
+  obj.stack = "stack...";
+  const err = fromErrorObject(obj);
+  assertInstanceOf(err, Error);
+  assertEquals(err.name, "Error");
+  assertEquals(err.message, "error");
+  assertEquals(err.stack, "stack...");
+});
 
-  await t.step("CustomError", () => {
-    const obj = toErrorObject(new CustomError("error", "foo", 10));
-    obj.stack = "stack...";
-    const err = fromErrorObject(obj);
-    assertInstanceOf(err, Error);
-    assertEquals(err.name, "ThisIsCustomError");
-    assertEquals(err.message, "error");
-    assertEquals(err.stack, "stack...");
-    assertEquals((err as CustomError).foo, "foo");
-    assertEquals((err as CustomError).bar, 10);
-  });
+await test("fromErrorObject with CustomError", () => {
+  const obj = toErrorObject(new CustomError("error", "foo", 10));
+  obj.stack = "stack...";
+  const err = fromErrorObject(obj);
+  assertInstanceOf(err, Error);
+  assertEquals(err.name, "ThisIsCustomError");
+  assertEquals(err.message, "error");
+  assertEquals(err.stack, "stack...");
+  assertEquals((err as CustomError).foo, "foo");
+  assertEquals((err as CustomError).bar, 10);
 });
diff --git a/package-lock.json b/package-lock.json
new file mode 100644
index 0000000..47876ba
--- /dev/null
+++ b/package-lock.json
@@ -0,0 +1,48 @@
+{
+  "name": "errorutil",
+  "lockfileVersion": 3,
+  "requires": true,
+  "packages": {
+    "": {
+      "dependencies": {
+        "@core/unknownutil": "npm:@jsr/core__unknownutil@^4.2.0",
+        "@cross/test": "npm:@jsr/cross__test@^0.0.9",
+        "@std/assert": "npm:@jsr/std__assert@^1.0.2"
+      }
+    },
+    "node_modules/@core/unknownutil": {
+      "name": "@jsr/core__unknownutil",
+      "version": "4.2.0",
+      "resolved": "https://npm.jsr.io/~/11/@jsr/core__unknownutil/4.2.0.tgz",
+      "integrity": "sha512-HA5TxLa7E1mSNwiG1oRPfeq09SSrr6OH9TIeM5ECy14Vzv3hnsxxQO4il6Nt24HwMwFt2NkJ/RUqWD07Kbyg4g=="
+    },
+    "node_modules/@cross/test": {
+      "name": "@jsr/cross__test",
+      "version": "0.0.9",
+      "resolved": "https://npm.jsr.io/~/11/@jsr/cross__test/0.0.9.tgz",
+      "integrity": "sha512-zwDSXQHw8n6k/gBj1Q67Td34Lb1PfkzLTggXnNZzcRO9SxcdAlzyOKFCF62kTFM7ZjVPqYvqu2gHzMLtj6cayw==",
+      "dependencies": {
+        "@jsr/cross__runtime": "^1.0.0"
+      }
+    },
+    "node_modules/@jsr/cross__runtime": {
+      "version": "1.0.0",
+      "resolved": "https://npm.jsr.io/~/11/@jsr/cross__runtime/1.0.0.tgz",
+      "integrity": "sha512-wUtjVBTk65ae4AKQRnxD5x3h4vVmopdKAYie/uS01Qolii2XQ81bKtRTvJ4kx133GYYgIAgyl3ihQ0OK8LcPmQ=="
+    },
+    "node_modules/@jsr/std__internal": {
+      "version": "1.0.1",
+      "resolved": "https://npm.jsr.io/~/11/@jsr/std__internal/1.0.1.tgz",
+      "integrity": "sha512-ssI1kvluIero6cCfiWNmYItqCR8QpQB+STBJoe/xQVZ79SDpoqjK5VF2Eq/2M+Dz8WbqHVmrXRCaGN162x+Ebw=="
+    },
+    "node_modules/@std/assert": {
+      "name": "@jsr/std__assert",
+      "version": "1.0.2",
+      "resolved": "https://npm.jsr.io/~/11/@jsr/std__assert/1.0.2.tgz",
+      "integrity": "sha512-xujHXXeT3zvMNZeCXiDyfiITaqP4rgH8wqHNUD0Iyr4c2R0Ea//zJ4pASA1utIEIxeVu1jpeSlHU4+pagscqgQ==",
+      "dependencies": {
+        "@jsr/std__internal": "^1.0.1"
+      }
+    }
+  }
+}
diff --git a/package.json b/package.json
new file mode 100644
index 0000000..33c1844
--- /dev/null
+++ b/package.json
@@ -0,0 +1,8 @@
+{
+  "type": "module",
+  "dependencies": {
+    "@core/unknownutil": "npm:@jsr/core__unknownutil@^4.2.0",
+    "@cross/test": "npm:@jsr/cross__test@^0.0.9",
+    "@std/assert": "npm:@jsr/std__assert@^1.0.2"
+  }
+}
diff --git a/raise_test.ts b/raise_test.ts
index 86844ee..533b542 100644
--- a/raise_test.ts
+++ b/raise_test.ts
@@ -1,6 +1,7 @@
+import { test } from "@cross/test";
 import { assertThrows } from "@std/assert";
 import { raise } from "./raise.ts";
 
-Deno.test("raise", () => {
+test("raise", () => {
   assertThrows(() => raise(new Error("error")), Error, "error");
 });
diff --git a/try_or_else_test.ts b/try_or_else_test.ts
index 79c95df..5aadb2e 100644
--- a/try_or_else_test.ts
+++ b/try_or_else_test.ts
@@ -1,58 +1,57 @@
+import { test } from "@cross/test";
 import { assertEquals, assertRejects, assertThrows } from "@std/assert";
 import { raise } from "./raise.ts";
 import { tryOrElse } from "./try_or_else.ts";
 
-Deno.test("tryOrElse", async (t) => {
-  const err = new Error("error");
-  const resolve = Promise.resolve.bind(Promise);
-  const reject = Promise.reject.bind(Promise);
+const err = new Error("error");
+const resolve = Promise.resolve.bind(Promise);
+const reject = Promise.reject.bind(Promise);
 
-  await t.step("sync", () => {
-    type T = number;
-    assertEquals(tryOrElse((): T => 1, () => 2), 1);
-    assertEquals(tryOrElse((): T => raise(err), () => 2), 2);
-  });
+await test("tryOrElse (sync)", () => {
+  type T = number;
+  assertEquals(tryOrElse((): T => 1, () => 2), 1);
+  assertEquals(tryOrElse((): T => raise(err), () => 2), 2);
+});
 
-  await t.step("sync (error)", () => {
-    type T = number;
-    assertThrows(
-      () => tryOrElse((): T => raise(err), () => raise(err)),
-      Error,
-      "error",
-    );
-  });
+await test("tryOrElse with Error (sync)", () => {
+  type T = number;
+  assertThrows(
+    () => tryOrElse((): T => raise(err), () => raise(err)),
+    Error,
+    "error",
+  );
+});
 
-  await t.step("async", async () => {
-    type T = Promise<number>;
-    assertEquals(await tryOrElse((): T => resolve(1), () => 2), 1);
-    assertEquals(await tryOrElse((): T => resolve(1), () => resolve(2)), 1);
-    assertEquals(await tryOrElse((): T => reject(err), () => 2), 2);
-    assertEquals(await tryOrElse((): T => reject(err), () => resolve(2)), 2);
-    assertEquals(await tryOrElse((): T => raise(err), () => 2), 2);
-    assertEquals(await tryOrElse((): T => raise(err), () => resolve(2)), 2);
-  });
+await test("tryOrElse (async)", async () => {
+  type T = Promise<number>;
+  assertEquals(await tryOrElse((): T => resolve(1), () => 2), 1);
+  assertEquals(await tryOrElse((): T => resolve(1), () => resolve(2)), 1);
+  assertEquals(await tryOrElse((): T => reject(err), () => 2), 2);
+  assertEquals(await tryOrElse((): T => reject(err), () => resolve(2)), 2);
+  assertEquals(await tryOrElse((): T => raise(err), () => 2), 2);
+  assertEquals(await tryOrElse((): T => raise(err), () => resolve(2)), 2);
+});
 
-  await t.step("async (error)", async () => {
-    type T = Promise<number>;
-    await assertRejects(
-      () => tryOrElse((): T => reject(err), () => reject(err)),
-      Error,
-      "error",
-    );
-    await assertRejects(
-      () => tryOrElse((): T => reject(err), () => raise(err)),
-      Error,
-      "error",
-    );
-    await assertRejects(
-      () => tryOrElse((): T => raise(err), () => reject(err)),
-      Error,
-      "error",
-    );
-    assertThrows(
-      () => tryOrElse((): T => raise(err), () => raise(err)),
-      Error,
-      "error",
-    );
-  });
+await test("tryOrElse with Error (async)", async () => {
+  type T = Promise<number>;
+  await assertRejects(
+    () => tryOrElse((): T => reject(err), () => reject(err)),
+    Error,
+    "error",
+  );
+  await assertRejects(
+    () => tryOrElse((): T => reject(err), () => raise(err)),
+    Error,
+    "error",
+  );
+  await assertRejects(
+    () => tryOrElse((): T => raise(err), () => reject(err)),
+    Error,
+    "error",
+  );
+  assertThrows(
+    () => tryOrElse((): T => raise(err), () => raise(err)),
+    Error,
+    "error",
+  );
 });
diff --git a/try_or_test.ts b/try_or_test.ts
index 0da63fe..4d22668 100644
--- a/try_or_test.ts
+++ b/try_or_test.ts
@@ -1,25 +1,24 @@
+import { test } from "@cross/test";
 import { assertEquals } from "@std/assert";
 import { raise } from "./raise.ts";
 import { tryOr } from "./try_or.ts";
 
-Deno.test("tryOr", async (t) => {
-  const err = new Error("error");
-  const resolve = Promise.resolve.bind(Promise);
-  const reject = Promise.reject.bind(Promise);
+const err = new Error("error");
+const resolve = Promise.resolve.bind(Promise);
+const reject = Promise.reject.bind(Promise);
 
-  await t.step("sync", () => {
-    type T = number;
-    assertEquals(tryOr((): T => 1, 2), 1);
-    assertEquals(tryOr((): T => raise(err), 2), 2);
-  });
+await test("tryOr (sync)", () => {
+  type T = number;
+  assertEquals(tryOr((): T => 1, 2), 1);
+  assertEquals(tryOr((): T => raise(err), 2), 2);
+});
 
-  await t.step("async", async () => {
-    type T = Promise<number>;
-    assertEquals(await tryOr((): T => resolve(1), 2), 1);
-    assertEquals(await tryOr((): T => resolve(1), resolve(2)), 1);
-    assertEquals(await tryOr((): T => reject(err), 2), 2);
-    assertEquals(await tryOr((): T => reject(err), resolve(2)), 2);
-    assertEquals(await tryOr((): T => raise(err), 2), 2);
-    assertEquals(await tryOr((): T => raise(err), resolve(2)), 2);
-  });
+await test("tryOr (async)", async () => {
+  type T = Promise<number>;
+  assertEquals(await tryOr((): T => resolve(1), 2), 1);
+  assertEquals(await tryOr((): T => resolve(1), resolve(2)), 1);
+  assertEquals(await tryOr((): T => reject(err), 2), 2);
+  assertEquals(await tryOr((): T => reject(err), resolve(2)), 2);
+  assertEquals(await tryOr((): T => raise(err), 2), 2);
+  assertEquals(await tryOr((): T => raise(err), resolve(2)), 2);
 });
diff --git a/unimplemented_test.ts b/unimplemented_test.ts
new file mode 100644
index 0000000..112c086
--- /dev/null
+++ b/unimplemented_test.ts
@@ -0,0 +1,7 @@
+import { test } from "@cross/test";
+import { assertThrows } from "@std/assert";
+import { unimplemented, UnimplementedError } from "./unimplemented.ts";
+
+test("unimplemented", () => {
+  assertThrows(() => unimplemented(), UnimplementedError);
+});
diff --git a/unreachable_test.ts b/unreachable_test.ts
new file mode 100644
index 0000000..404e9c5
--- /dev/null
+++ b/unreachable_test.ts
@@ -0,0 +1,7 @@
+import { test } from "@cross/test";
+import { assertThrows } from "@std/assert";
+import { unreachable, UnreachableError } from "./unreachable.ts";
+
+test("unreachable", () => {
+  assertThrows(() => unreachable(), UnreachableError);
+});