diff --git a/.gitignore b/.gitignore
index 7fb9ee4..c1a02d8 100644
--- a/.gitignore
+++ b/.gitignore
@@ -2,4 +2,5 @@ node_modules
 yarn-error.log
 .vscode
 dist
-tsconfig.tsbuildinfo
\ No newline at end of file
+tsconfig.tsbuildinfo
+install-state.gz
diff --git a/.yarn/install-state.gz b/.yarn/install-state.gz
deleted file mode 100644
index bbfa25c..0000000
Binary files a/.yarn/install-state.gz and /dev/null differ
diff --git a/examples/package.json b/examples/package.json
index 5bbefff..3dbc1ca 100644
--- a/examples/package.json
+++ b/examples/package.json
@@ -1,3 +1,3 @@
 {
-  "type": "commonjs"
+  "type": "module"
 }
diff --git a/examples/starwars.ts b/examples/starwars.ts
index 81cdcc7..6dc1bc3 100644
--- a/examples/starwars.ts
+++ b/examples/starwars.ts
@@ -1,15 +1,15 @@
-import type { InterfaceType } from '../src';
-import type { Connection, ConnectionArguments, Edge } from '../src/relay';
-import { buildGraphQLSchema, Gql } from '../src';
+import type { InterfaceType } from '../src/index.js';
+import type { Connection, ConnectionArguments, Edge } from '../src/relay.js';
+import { buildGraphQLSchema, Gql } from '../src/index.js';
 import {
   connectionArgs,
   connectionDefinitions,
   nodeDefinitions,
-} from '../src/relay';
+} from '../src/relay.js';
 import express = require('express');
 import graphqlHTTP = require('express-graphql');
 
-declare module '../src/types' {
+declare module '../src/types.js' {
   interface GqlContext {
     contextContent: string;
   }
diff --git a/examples/tsconfig.json b/examples/tsconfig.json
index fd20472..8cb0eec 100644
--- a/examples/tsconfig.json
+++ b/examples/tsconfig.json
@@ -3,6 +3,6 @@
   "files": ["./starwars.ts"],
   "compilerOptions": {
     "target": "ES2019",
-    "module": "commonjs"
+    "module": "NodeNext"
   }
 }
diff --git a/jest.config.cjs b/jest.config.cjs
index 4a5b465..7c426d6 100644
--- a/jest.config.cjs
+++ b/jest.config.cjs
@@ -1,4 +1,7 @@
 module.exports = {
   preset: 'ts-jest',
   testEnvironment: 'node',
+  moduleNameMapper: {
+    '^(\\.{1,2}/.*)\\.js$': '$1',
+ },
 };
diff --git a/package.json b/package.json
index 76ac739..42b73b3 100644
--- a/package.json
+++ b/package.json
@@ -2,17 +2,17 @@
   "name": "gqtx",
   "version": "0.9.0",
   "type": "module",
-  "main": "cjs/index.js",
+  "main": "cjs/index.cjs",
   "module": "index.js",
   "types": "index.d.ts",
   "exports": {
     ".": {
       "import": "./index.js",
-      "require": "./cjs/index.js"
+      "require": "./cjs/index.cjs"
     },
     "./relay": {
       "import": "./relay.js",
-      "require": "./cjs/relay.js"
+      "require": "./cjs/relay.cjs"
     },
     "./package.json": "./package.json",
     "./": "./"
diff --git a/rollup.config.js b/rollup.config.js
index 6d071ae..008f09c 100644
--- a/rollup.config.js
+++ b/rollup.config.js
@@ -28,6 +28,7 @@ export default {
     {
       dir: isCJSBuild ? 'dist/cjs' : 'dist',
       format: isCJSBuild ? 'cjs' : 'esm',
+      entryFileNames: isCJSBuild ? '[name].cjs' : '[name].js',
     },
   ],
   plugins: [
diff --git a/src/build.ts b/src/build.ts
index 3af9a0a..51f2133 100644
--- a/src/build.ts
+++ b/src/build.ts
@@ -1,5 +1,5 @@
 import * as graphql from 'graphql';
-import {
+import type {
   Schema,
   InputType,
   OutputType,
@@ -11,7 +11,7 @@ import {
   GqlContext,
   UnionType,
   InterfaceType,
-} from './types';
+} from './types.js';
 
 export function buildGraphQLSchema<RootSrc>(
   schema: Schema<RootSrc>
diff --git a/src/define.ts b/src/define.ts
index 252d909..a07ef26 100644
--- a/src/define.ts
+++ b/src/define.ts
@@ -1,5 +1,5 @@
 import * as graphql from 'graphql';
-import {
+import type {
   ScalarType,
   EnumType,
   EnumValue,
@@ -20,7 +20,7 @@ import {
   SubscriptionObjectType,
   PromiseOrValue,
   GqlContext,
-} from './types';
+} from './types.js';
 
 type ExtensionsMap = {
   field?: {
diff --git a/src/index.ts b/src/index.ts
index 6532a3d..6996044 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -1,7 +1,7 @@
-export * from './types';
-export * from './define';
+export * from './types.js';
+export * from './define.js';
 export {
   buildGraphQLSchema,
   toGraphQLInputType,
   toGraphQLOutputType,
-} from './build';
+} from './build.js';
diff --git a/src/relay.ts b/src/relay.ts
index 1eb6db9..c84bc4e 100644
--- a/src/relay.ts
+++ b/src/relay.ts
@@ -5,8 +5,8 @@ import type {
   TOfArgMap,
   GqlContext,
   ObjectType,
-} from './types';
-import { Gql } from './define';
+} from './types.js';
+import { Gql } from './define.js';
 import { GraphQLResolveInfo } from 'graphql';
 
 // Adapted from
diff --git a/test-api/api.ts b/test-api/api.ts
index 4a7586e..5a209d2 100644
--- a/test-api/api.ts
+++ b/test-api/api.ts
@@ -1,6 +1,6 @@
-import { Gql, ObjectType } from '../src';
+import { Gql, ObjectType } from '../src/index.js';
 
-declare module '../src/types' {
+declare module '../src/types.js' {
   interface Context {
     contextContent: string;
   }
diff --git a/tsconfig.json b/tsconfig.json
index 9513569..c4a0ac2 100644
--- a/tsconfig.json
+++ b/tsconfig.json
@@ -2,7 +2,7 @@
   "compilerOptions": {
     "target": "ES2019",
     "module": "ESNext",
-    "moduleResolution": "node",
+    "moduleResolution": "NodeNext",
     "rootDir": "src",
     "outDir": "dist",
     "declaration": true,