Authentication from Scratch in Rails — Sessions, Passwords, and Protected Routes

Authentication in Rails doesn't need to be magic. You're going to build it from scratch so you understand every piece. By the end, you'll have sessions, passwords, and protected routes working. No gems that hide the logic. Why Build It Yourself? Devise is great for production. But if you don't understand what it's doing, you're cargo-culting security. Build it once manually, then decide if you want the abstraction. The Setup Start with a user model: rails generate mod