🔐 From 0 Production-Grade Security

“If it works on localhost, hackers say thank you.” Let’s go from completely insecure → production-ready security in simple steps. 0. The Reality Check Every app is vulnerable by default Security is NOT a feature → it’s a layered system Goal: make hacking too expensive & annoying 1. Basic Hygiene (Don’t Be an Easy Target) Use HTTPS only (no excuses) // Express.js app . use (( req , res , next ) => { if ( req . protocol === ' http ' ) { return res . redirect ( `https:// ${ req . headers . host }${ req . url } ` ); } next (); }); Store passwords with hashing ( bcrypt / argon2 ) import bcrypt from " bcrypt " ; const hashed = await bcrypt . hash ( password , 10 ); Never store secrets in code → use env variables // ❌ BAD const DB_PASSWORD = " mysecret " ; // ✅ GOOD const DB_PASSWORD = process . env . DB_PASSWORD ; Validate ALL inputs (frontend ≠ security) import Joi from " joi " ; const schema = Joi . object ({ email : Joi . string (). email (). required (), password : Joi . string (). min (