diff --git a/examples/node_simple.js b/examples/node_simple.ts
similarity index 100%
rename from examples/node_simple.js
rename to examples/node_simple.ts
diff --git a/test/urdfjoint.test.js b/test/urdfjoint.test.ts
similarity index 100%
rename from test/urdfjoint.test.js
rename to test/urdfjoint.test.ts
diff --git a/tsconfig.build.json b/tsconfig.build.json
index aea2a5a68..def8e0e40 100644
--- a/tsconfig.build.json
+++ b/tsconfig.build.json
@@ -7,8 +7,8 @@
     "moduleResolution": "bundler",
 
     /* JavaScript Support */
-    "allowJs": true /* Allow JavaScript files to be a part of your program. Use the 'checkJS' option to get errors from these files. */,
-    "checkJs": true /* Enable error reporting in type-checked JavaScript files. */,
+    "allowJs": false /* Allow JavaScript files to be a part of your program. Use the 'checkJS' option to get errors from these files. */,
+    "checkJs": false /* Enable error reporting in type-checked JavaScript files. */,
 
     /* Build Options */
     "rootDir": "." /* Specify the root folder within your source files. */,