Environment Setup

Environment setup is a configuration-boundary job. Keep the main skill focused on env ownership, precedence, validation, and safe secret handoff instead of turning it into generic machine setup or deployment automation.

Read references/env-precedence-and-visibility.md when env-file layering, public/private split, or framework visibility rules are the main risk. Read references/validation-and-secret-handoff.md when the problem is required variable validation, .env.example discipline, CI/prod secret injection, or rotation handoff.

When to use this skill

• Structure .env, .env.local, .env.example, CI, and production config
• Separate public, private, secret, and runtime-only environment values
• Add typed env validation and fail-fast startup checks
• Clean up config drift between local, staging, preview, CI, and production
• Decide what should live in env vars versus checked-in config files