Feature Development
Workflow command scaffold for feature-development in everything-claude-code.
- Type
- Slash Command
- Repository
- affaan-m/ECC
- GitHub stars
- 268k
- License
- MIT
- Repo last updated
- Sep 24, 2026
- Source file
- .claude/commands/feature-development.md
What Feature Development is
Feature Development is a slash command published in the affaan-m/ECC repository on GitHub, which has about 268k stars. The repository describes itself as: “The agent harness performance optimization system. Skills, instincts, memory, security, and research-first development for Claude Code, Codex, Opencode, Cursor and beyond.”
A slash command is a reusable prompt saved as a markdown file and run by typing its name after a slash. In Claude Code, custom commands have been merged into skills: a file in .claude/commands/ and a skill folder in .claude/skills/ both create the same kind of command, and existing command files keep working.
Feature Development gives you a repeatable way to run the same instructions without retyping them, optionally with arguments.
How to install Feature Development
Claude Code
- Download feature-development.md from the repository.
- Save it to ~/.claude/commands/ (all projects) or .claude/commands/ (one project). As a skill, you can instead save it as ~/.claude/skills/<name>/SKILL.md.
- Run it by typing / followed by its name.
Claude Cowork
- Turn the command into a skill: create a folder with the file saved as SKILL.md and zip it.
- In Customize → Skills, click +, then upload the ZIP.
- Run it from any task with / and the skill name.
New to extending Cowork? Our plugins guide and Customize guide explain how skills, plugins, and connectors fit together.
Inside the source file
An excerpt from .claude/commands/feature-development.md, shared under the repository's MIT license. Read the full file on GitHub.
Use this workflow when working on feature-development in everything-claude-code.
Goal
Standard feature implementation workflow
Common Files
- manifests/*
- schemas/*
- **/.test.
- /api/
Suggested Sequence
- Understand the current state and failure mode before editing.
- Make the smallest coherent change that satisfies the workflow goal.
- Run the most relevant verification for touched files.
- Summarize what changed and what still needs review.
Typical Commit Signals
- Add feature implementation
- Add tests for feature
- Update documentation
Notes
- Treat this as a scaffold, not a hard-coded script.
- Update the command if the workflow evolves materially.
Before you install
- Read the whole file first. Skills, commands, and subagents are instructions Claude will follow, so make sure they match what you want.
- Check which tools, scripts, or MCP servers it uses. Local servers and scripts run with your permissions.
- Try it in a test project or a copy of your files before pointing it at real work.
- Pin the version you tested, and review changes before updating.
- Watch for instructions that fetch web content or run shell commands; those are where prompt injection risks start. See our prompt injection guide.
FAQ
What is Feature Development?
Feature Development is a slash command for Claude Code and Claude Cowork from the affaan-m/ECC repository on GitHub. Workflow command scaffold for feature-development in everything-claude-code.
How do I install Feature Development in Claude Code?
Download feature-development.md from the repository. Save it to ~/.claude/commands/ (all projects) or .claude/commands/ (one project). As a skill, you can instead save it as ~/.claude/skills/<name>/SKILL.md. Run it by typing / followed by its name.
Can I use Feature Development in Claude Cowork?
Turn the command into a skill: create a folder with the file saved as SKILL.md and zip it. In Customize → Skills, click +, then upload the ZIP. Run it from any task with / and the skill name.
Is Feature Development safe to install?
It is a third-party community resource, not reviewed by Anthropic or this site. Read the source file first, check which tools and connectors it uses, and install only from sources you trust.
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