DevContainer/Hook/postCreateCommand

• postCreateCommand

  • Overview

    • postCreateCommand runs inside the container after the environment has been created and the workspace is mounted.
    • In practice, this is the hook many teams use for their main project setup step.

  • When It Is Called

    • After first creation, once the workspace is ready inside the container.
    • It does not rerun on ordinary container restarts.

  • Why You Would Use It

    • Use it for project-level setup that depends on the actual checked-out workspace being present.
    • Typical cases include:
      • Running npm install, pnpm install, pip install, or similar dependency installation
      • Finalizing project configuration
      • Running setup scripts that need the workspace mount
      • Preparing local development tooling after the container exists

  • Practical Distinction

    • postCreateCommand is usually the best fit when the setup depends on repository files being mounted and available.
    • That is why it is often preferred over [[DevContainer/Hook/onCreateCommand]] for the main dependency-install step.

  • Misconceptions

    • It runs every time the container starts -> False. It is a creation-time hook, not a restart hook.
    • It should replace image builds for everything -> False. Stable base tooling often belongs in the image, not in a post-create step.

  • Related

    • DevContainer/Hook