diff --git a/scripts/build-npm.js b/scripts/build-npm.js
index a1f3969..cbc31fd 100644
--- a/scripts/build-npm.js
+++ b/scripts/build-npm.js
@@ -85,7 +85,7 @@ try {
   fs.mkdirSync(dir + '/npm/watcher');
 } catch (err) { }
 for (let file of pkg.files) {
-  fs.copyFileSync(`${dir}/${file}`, `npm/watcher/${file}`);
+  fs.cpSync(`${dir}/${file}`, `npm/watcher/${file}`, {recursive: true});
 }
 pkg.optionalDependencies = optionalDependencies;
 fs.writeFileSync(`${dir}/npm/watcher/package.json`, JSON.stringify(pkg, false, 2) + '\n');