Dev Container Feature Creator

This skill acts as an implementation manual to assist you in scaffolding, developing, updating, and extensively testing Dev Container Features. It leverages the official Dev Container Features specification, testing framework, and authoring best practices.

Core Principles

• Mandatory Planning: Before scaffolding or modifying a feature, you MUST draft a design plan and obtain user approval. The plan should outline the feature ID, options, installation strategy, and testing scenarios.
• Idempotency: Installation scripts MUST be idempotent. They should be safe to run multiple times with different options without failing or causing unintended side effects.
• OS Compatibility: Installation scripts should verify the OS/distro at the beginning and support a diverse set of base images, defaulting to sh or safely bootstrapping bash.
• Handling Non-Root Users: Scripts run as root, but the final user might not be root. Use _REMOTE_USER to set permissions appropriately.
• Comprehensive Testing: Always implement auto-generated tests, scenario tests, and duplicate tests using the devcontainer features test command framework.

Workflow

Follow these steps to construct or update a Dev Container Feature:

1. Analyze & Scaffold

• Check the workspace structure. Features usually live in src/<feature-name>/ and their tests in test/<feature-name>/.
• Create these directories if they don't exist.