ext.dev Documentation

Welcome to the ext.dev developer documentation. This guide covers the Claude Code-based development workflow used across all ext.dev projects.

What is Claude Code?

Claude Code is an AI-powered coding assistant that runs directly inside Visual Studio Code. At ext.dev, we use it with a set of custom slash commands that automate common development tasks — from picking up client issues to deploying code.

Sections

Onboarding

Step-by-step instructions to get your development environment ready:

• Installing Visual Studio Code
• Installing Claude Code
• Activating Claude Code in VS Code

Command Reference

Documentation for every custom slash command available in our projects:

Command	Description
/issue	Fetch and implement a development issue
/clientissue	Read a client issue, plan, and create a dev issue
/clientissues	Browse and complete client issues end-to-end
/clientfeedback	Post client-facing status updates
/rollout	Commit, push, and update GitLab issues
/merge	Create and merge GitLab merge requests
/composer	Manage PHP Composer dependencies in Docker
/techdebt	Scan touched files for technical debt
/learnings	Capture reusable project knowledge
/production-health	Check production server health

Typical Workflow

A typical development cycle looks like this:

1. Pick an issue — /clientissues to browse client issues, or /issue 123 for a specific dev issue
2. Implement — Claude Code helps you write the code
3. Check quality — /techdebt scans for problems
4. Save knowledge — /learnings captures insights for future sessions
5. Deploy — /rollout #123 commits and pushes
6. Merge — /merge staging or /merge main
7. Notify the client — /clientfeedback posts a German status update