Every Node.js project I've ever worked on has the same invisible vulnerability. Somewhere in the codebase, there's a line like this: const db = new Client ({ url : process . env . DATABASE_URL }) It works in development. It works in staging. And then one day, in production, the variable is missing, misspelled in the CI config, forgotten in a new environment, silently dropped during a secrets rotation. The app starts. No error. No warning. Just undefi...