diff --git a/src/node/NodeBasisEncoder.ts b/src/node/NodeBasisEncoder.ts
index db96b85..82f6020 100644
--- a/src/node/NodeBasisEncoder.ts
+++ b/src/node/NodeBasisEncoder.ts
@@ -1,5 +1,5 @@
-import { IBasisModule, IEncodeOptions, SourceType } from "../type";
-import { applyInputOptions } from "../utils";
+import { IBasisModule, IEncodeOptions, SourceType } from "../type.js";
+import { applyInputOptions } from "../utils.js";
 import BASIS from "./basis/basis_encoder.js";
 
 let promise: Promise<IBasisModule> | null = null;
diff --git a/src/node/index.ts b/src/node/index.ts
index 0c3385c..da1948a 100644
--- a/src/node/index.ts
+++ b/src/node/index.ts
@@ -1,5 +1,5 @@
-import { IEncodeOptions } from "../type";
-import { nodeEncoder } from "./NodeBasisEncoder";
+import { IEncodeOptions } from "../type.js";
+import { nodeEncoder } from "./NodeBasisEncoder.js";
 
 export function encodeToKTX2(imageBuffer: Uint8Array, options: Partial<IEncodeOptions> = {}): Promise<Uint8Array> {
   if (!options.imageDecoder) {
diff --git a/src/utils.ts b/src/utils.ts
index de08aa8..3b1c8fd 100644
--- a/src/utils.ts
+++ b/src/utils.ts
@@ -1,4 +1,4 @@
-import { IBasisEncoder, IEncodeOptions } from "./type";
+import { IBasisEncoder, IEncodeOptions } from "./type.js";
 
 export const DefaultOptions = {
   enableDebug: false,
diff --git a/src/web/BrowserBasisEncoder.ts b/src/web/BrowserBasisEncoder.ts
index 4747856..d375530 100644
--- a/src/web/BrowserBasisEncoder.ts
+++ b/src/web/BrowserBasisEncoder.ts
@@ -1,6 +1,6 @@
 import { read, write } from "ktx-parse";
-import { BasisTextureType, IBasisModule, IEncodeOptions, SourceType } from "../type";
-import { applyInputOptions } from "../utils";
+import { BasisTextureType, IBasisModule, IEncodeOptions, SourceType } from "../type.js";
+import { applyInputOptions } from "../utils.js";
 
 declare function importScripts(...args: any): any;
 
diff --git a/src/web/index.ts b/src/web/index.ts
index 1d279a4..5cb8c8e 100644
--- a/src/web/index.ts
+++ b/src/web/index.ts
@@ -1,6 +1,6 @@
-import { IEncodeOptions } from "../type";
-import { browserEncoder } from "./BrowserBasisEncoder";
-import { decodeImageBitmap } from "./decodeImageData";
+import { IEncodeOptions } from "../type.js";
+import { browserEncoder } from "./BrowserBasisEncoder.js";
+import { decodeImageBitmap } from "./decodeImageData.js";
 
 export function encodeToKTX2(imageBuffer: Uint8Array, options: Partial<IEncodeOptions> = {}): Promise<Uint8Array> {
   options.imageDecoder ??= decodeImageBitmap;
diff --git a/tsconfig.json b/tsconfig.json
index e6a58bb..4c14461 100644
--- a/tsconfig.json
+++ b/tsconfig.json
@@ -3,11 +3,11 @@
     "target": "ES2020",
     "useDefineForClassFields": true,
     "lib": ["ES2020", "DOM", "DOM.Iterable"],
-    "module": "ESNext",
+    "module": "NodeNext",
     "skipLibCheck": true,
 
     /* Bundler mode */
-    "moduleResolution": "bundler",
+    "moduleResolution": "NodeNext",
     "allowImportingTsExtensions": false,
     "resolveJsonModule": true,
     "isolatedModules": true,