diff --git a/src/async.spec.ts b/src/async.spec.ts
index bb9004b..a113469 100644
--- a/src/async.spec.ts
+++ b/src/async.spec.ts
@@ -1,6 +1,6 @@
 import { describe, expect, expectTypeOf, it } from 'vitest';
 
-import { Async } from './async';
+import { Async } from './async.js';
 
 describe('Async', () => {
   it('.Pending', () => {
diff --git a/src/maybe.spec.ts b/src/maybe.spec.ts
index 8cdcd8c..9ad937a 100644
--- a/src/maybe.spec.ts
+++ b/src/maybe.spec.ts
@@ -1,6 +1,6 @@
 import { describe, expect, expectTypeOf, it } from 'vitest';
 
-import { Maybe } from './maybe';
+import { Maybe } from './maybe.js';
 
 describe('Maybe', () => {
   it('.None', () => {
diff --git a/src/result.spec.ts b/src/result.spec.ts
index 1c9543e..c1dba37 100644
--- a/src/result.spec.ts
+++ b/src/result.spec.ts
@@ -1,6 +1,6 @@
 import { describe, expect, expectTypeOf, it } from 'vitest';
 
-import { Result } from './result';
+import { Result } from './result.js';
 
 describe('Result', () => {
   it('.Err', () => {
diff --git a/tsconfig.json b/tsconfig.json
index d3d1045..aa99bbb 100644
--- a/tsconfig.json
+++ b/tsconfig.json
@@ -6,8 +6,8 @@
     "forceConsistentCasingInFileNames": true,
     "isolatedModules": true,
     "lib": ["dom", "dom.iterable", "esnext"],
-    "module": "esnext",
-    "moduleResolution": "bundler",
+    "module": "nodenext",
+    "moduleResolution": "nodenext",
     "noErrorTruncation": true,
     "noFallthroughCasesInSwitch": true,
     "noImplicitAny": true,