JavaScript Tools

JS Utilities:
Transpiling / Type Checking (ES to ES):
Code-analysis Engine:
JavaScript Compatibility Checker:
Linting/Hinting & Style Linter:
Unit Testing:
Testing Assertions for Unit Testing:
Test Spies, Stubs, and Mocks for Unit Testing:
Code Formater/Beautifier:
Performance Testing:
Visualization, Static Analysis, Complexity, Coverage Tools:
Optimizer:
Obfuscate:
Sharable/Runnable Code Editors:
Online Regular Expression Editors/Visual Tools:
Authoring Convention Tools:

https://github.com/trending?l=javascript&since=monthly

Most Depended upon Packages on NPM:

https://www.npmjs.com/browse/depended