描述
Build reproducible developer environments for real projects: local toolchains, runtime versions, Docker Compose or dev containers, onboarding flows, local service parity, bootstrap scripts, and environment troubleshooting. Use when the user needs a repo to run consistently across machines, containers, or staged environments, even if they only say setup dev environment, onboarding, Docker, devcontainer, local parity, bootstrap, or make this runnable. This is the canonical broader environment-setup skill. Route narrower `.env` and app-config questions to `environment-setup`.