diff --git a/jest.config.base.js b/jest.config.base.js
index cfdcf830..992fc35b 100644
--- a/jest.config.base.js
+++ b/jest.config.base.js
@@ -2,5 +2,5 @@
 module.exports = {
   preset: 'ts-jest/presets/js-with-ts',
   testEnvironment: 'node',
-  modulePathIgnorePatterns: ['out', 'e2e_tests'],
+  modulePathIgnorePatterns: ['out', 'e2e_tests', 'dist', 'esm'],
 };
diff --git a/packages/antlr4-c3/jest.config.js b/packages/antlr4-c3/jest.config.cjs
similarity index 100%
rename from packages/antlr4-c3/jest.config.js
rename to packages/antlr4-c3/jest.config.cjs
diff --git a/packages/language-support/jest.config.js b/packages/language-support/jest.config.js
index ec6bcb8c..960ecdbb 100644
--- a/packages/language-support/jest.config.js
+++ b/packages/language-support/jest.config.js
@@ -1,3 +1,3 @@
-const sharedConfig = require('../../jest.config.base.js')
+const sharedConfig = require('../../jest.config.base.js');
 
-module.exports = sharedConfig
+module.exports = sharedConfig;
diff --git a/packages/react-codemirror-experimental/jest.config.js b/packages/react-codemirror-experimental/jest.config.js
index 216fb49b..6e6586c6 100644
--- a/packages/react-codemirror-experimental/jest.config.js
+++ b/packages/react-codemirror-experimental/jest.config.js
@@ -1,3 +1,3 @@
-import sharedConfig from '../../jest.config.base.js';
+const sharedConfig = require('../../jest.config.base');
 
-export default sharedConfig;
+module.exports = sharedConfig;
diff --git a/packages/react-codemirror-experimental/tsconfig.json b/packages/react-codemirror-experimental/tsconfig.json
index b42d82b9..e10b8b31 100644
--- a/packages/react-codemirror-experimental/tsconfig.json
+++ b/packages/react-codemirror-experimental/tsconfig.json
@@ -2,6 +2,7 @@
   "extends": "../../tsconfig.base.json",
   "include": ["src"],
   "compilerOptions": {
-    "jsx": "react-jsx"
+    "jsx": "react-jsx",
+    "allowJs": true
   }
 }