I Audited 12 Open Source Projects' JWT Implementations and Found the Same 6 Mistakes in All of Them

It started with a throwaway comment in a code review. I was scanning through a popular Node.js starter template on GitHub — one with over 4,000 stars, regularly featured in "best Express boilerplate" roundup articles. The kind of repo junior developers clone on day one and senior developers use as a starting point for new services. And buried inside config/default.js , I found this: module . exports = { jwtSecret : " secret " , jwtExpiry : " 7d " , }; Not a placeholder. Not a comment warning you