env-setup

# Environment Configuration ## Non-Negotiable Rules | Rule | Why | |------|-----| | NEVER commit .env to git | Secrets persist in history forever | | NEVER log secret values | Logs stored in plain text, forwarded | | NEVER hardcode secrets | Source code is widely shared | | ALWAYS use .env.example | Documents vars without exposing values | | ALWAYS add .env* to .gitignore FIRST | Prevents accidental commit | | ALWAYS validate config at startup | Fail fast, not hours into production | ## .gitignore (add before creating .env) ```gitignore .env .env.* !.env.example *.pem *.key credentials.json ``` ## Naming Conventions - UPPER_SNAKE_CASE: `DATABASE_URL`, `JWT_SECRET` - Prefix by service: `DB_`, `REDIS_`, `AWS_` - Booleans: `ENABLE_CACHE=true` (not 1/yes) - Feature flags: `FEATURE_*` ## Key Patterns - **No defaults for secrets** — force explicit configuration - **Validate at startup** with Zod/Joi/Pydantic, not at first use - **Unique secrets per environment** — one leak shouldn't compromise all - **Rotate leaked secrets immediately** — check git history, audit access logs - **Process env always wins** — CI/CD overrides file-based config