diff --git a/package.json b/package.json
index 5441842..67e4dd4 100644
--- a/package.json
+++ b/package.json
@@ -8,11 +8,24 @@
   "module": "./dist.esm/index.mjs",
   "cdn": "./dist.umd/msgpack.min.js",
   "unpkg": "./dist.umd/msgpack.min.js",
-  "types": "./dist.esm/index.d.ts",
+  "types": "./dist.esm/index.d.mts",
+  "exports": {
+    ".": {
+      "import": {
+        "types": "./dist.esm/index.d.mts",
+        "default": "./dist.esm/index.mjs"
+      },
+      "require": {
+        "types": "./dist.cjs/index.d.cts",
+        "default": "./dist.cjs/index.cjs"
+      }
+    },
+    "./package.json": "./package.json"
+  },
   "sideEffects": false,
   "scripts": {
     "build": "npm publish --dry-run",
-    "prepare": "npm run clean && webpack --bail && tsgo --build tsconfig.dist.cjs.json tsconfig.dist.esm.json && tsimp tools/fix-ext.mts --mjs dist.esm/*.js dist.esm/*/*.js && tsimp tools/fix-ext.mts --cjs dist.cjs/*.js dist.cjs/*/*.js",
+    "prepare": "npm run clean && webpack --bail && tsgo --build tsconfig.dist.cjs.json tsconfig.dist.esm.json && tsimp tools/fix-ext.mts --mjs dist.esm/*.js dist.esm/*/*.js dist.esm/*.d.ts dist.esm/*/*.d.ts && tsimp tools/fix-ext.mts --cjs dist.cjs/*.js dist.cjs/*/*.js dist.cjs/*.d.ts dist.cjs/*/*.d.ts",
     "prepublishOnly": "npm run test:dist",
     "clean": "rimraf build dist dist.*",
     "test": "mocha 'test/**/*.test.ts'",
diff --git a/tools/fix-ext.mts b/tools/fix-ext.mts
index bd6f737..d7cd283 100644
--- a/tools/fix-ext.mts
+++ b/tools/fix-ext.mts
@@ -4,25 +4,39 @@ const mode = process.argv[2]; // --cjs or --mjs
 const files = process.argv.slice(3);
 
 const ext = mode === "--cjs" ? "cjs" : "mjs";
+const dtsExt = mode === "--cjs" ? "d.cts" : "d.mts";
 
 console.info(`Fixing ${mode} files with extension ${ext}`);
 
 for (const file of files) {
-  const fileMjs = file.replace(/\.js$/, `.${ext}`);
-  console.info(`Processing ${file} => ${fileMjs}`);
-  // .js => .mjs
-  const content = fs.readFileSync(file).toString("utf-8");
-  const newContent = content
-    .replace(/\bfrom "(\.\.?\/[^"]+)\.js";/g, `from "$1.${ext}";`)
-    .replace(/\bimport "(\.\.?\/[^"]+)\.js";/g, `import "$1.${ext}";`)
-    .replace(/\brequire\("(\.\.?\/[^"]+)\.js"\)/g, `require("$1.${ext}");`)
-    .replace(/\/\/# sourceMappingURL=(.+)\.js\.map$/, `//# sourceMappingURL=$1.${ext}.map`);
-  fs.writeFileSync(fileMjs, newContent);
-  fs.unlinkSync(file);
+  if (file.endsWith(".d.ts")) {
+    // Handle declaration files: .d.ts => .d.mts or .d.cts
+    const newFile = file.replace(/\.d\.ts$/, `.${dtsExt}`);
+    console.info(`Processing ${file} => ${newFile}`);
+    const content = fs.readFileSync(file).toString("utf-8");
+    // Fix import paths: .ts => .mjs or .cjs
+    const newContent = content
+      .replace(/\bfrom "(\.\.?\/[^"]+)\.ts";/g, `from "$1.${ext}";`)
+      .replace(/\bimport "(\.\.?\/[^"]+)\.ts";/g, `import "$1.${ext}";`);
+    fs.writeFileSync(newFile, newContent);
+    fs.unlinkSync(file);
+  } else if (file.endsWith(".js")) {
+    // Handle JS files: .js => .mjs or .cjs
+    const fileMjs = file.replace(/\.js$/, `.${ext}`);
+    console.info(`Processing ${file} => ${fileMjs}`);
+    const content = fs.readFileSync(file).toString("utf-8");
+    const newContent = content
+      .replace(/\bfrom "(\.\.?\/[^"]+)\.js";/g, `from "$1.${ext}";`)
+      .replace(/\bimport "(\.\.?\/[^"]+)\.js";/g, `import "$1.${ext}";`)
+      .replace(/\brequire\("(\.\.?\/[^"]+)\.js"\)/g, `require("$1.${ext}");`)
+      .replace(/\/\/# sourceMappingURL=(.+)\.js\.map$/, `//# sourceMappingURL=$1.${ext}.map`);
+    fs.writeFileSync(fileMjs, newContent);
+    fs.unlinkSync(file);
 
-  // .js.map => .mjs.map
-  const mapping = JSON.parse(fs.readFileSync(`${file}.map`).toString("utf-8"));
-  mapping.file = mapping.file.replace(/\.js$/, ext);
-  fs.writeFileSync(`${fileMjs}.map`, JSON.stringify(mapping));
-  fs.unlinkSync(`${file}.map`);
+    // .js.map => .mjs.map
+    const mapping = JSON.parse(fs.readFileSync(`${file}.map`).toString("utf-8"));
+    mapping.file = mapping.file.replace(/\.js$/, ext);
+    fs.writeFileSync(`${fileMjs}.map`, JSON.stringify(mapping));
+    fs.unlinkSync(`${file}.map`);
+  }
 }
diff --git a/tsconfig.dist.cjs.json b/tsconfig.dist.cjs.json
index 8225a84..3a5c60d 100644
--- a/tsconfig.dist.cjs.json
+++ b/tsconfig.dist.cjs.json
@@ -3,7 +3,7 @@
   "compilerOptions": {
     "module": "CommonJS",
     "outDir": "./dist.cjs",
-    "declaration": false,
+    "declaration": true,
     "noEmitOnError": true,
     "noEmit": false,
     "rewriteRelativeImportExtensions": true,