codebase-map-plus

Built on affaan-m/ECC by @affaan-m (248,470 stars, MIT). All credit for the original idea to them. This fork improves and repackages it; upstream license preserved in UPSTREAM_LICENSE.

A Claude Code skill that maps a new codebase, finds key paths and rules, and drafts a safe starter CLAUDE.md.

Built for developers who join a new repo, switch teams, review old code, or want Claude Code to learn a project fast.

A new codebase can feel like a maze.

Docs may be old. Start files may be hard to find. Large made folders can hide the code that matters. Rules may live in many places.

This skill gives Claude Code a clear, safe process. It scans the repo, maps the main parts, traces a real flow, finds test commands, and marks facts that still need review.

It is a single file with no added tools or packages. It plugs into your normal Claude Code flow.

mkdir -p ~/.claude/skills/codebase-onboarding && curl -fsSL https://raw.githubusercontent.com/codebase-map-plus/codebase-map-plus/main/skill/SKILL.md -o ~/.claude/skills/codebase-onboarding/SKILL.md

Open Claude Code in a project and ask:

Onboard me to this repo and draft a CLAUDE.md.

Expected output:

Project Summary
Project Map
Entry Points
Main Flow
Tools and Commands
Code Rules
Risks and Open Questions
Starter CLAUDE.md

Claude will check project rules first. It will then find package files, tools, apps, routes, jobs, tests, and key folders. It will trace at least one path through the code.

The CLAUDE.md is shown as a draft. Claude writes it only when you ask for a file change.

• Rewritten from Japanese into clearer, plain English with more actionable wording.
• Adds explicit attribution/licensing guidance and preserves ECC credit.
• Adds safety rules: respect existing project instructions, avoid unauthorized file changes or risky operations, and never expose secrets.
• Expands discovery substantially, covering more ecosystems, CI, multiple entry points, generated folders, test commands, and evidence-based framework identification.
• Adds deeper architecture tracing and convention classification (Stated rule, Seen pattern, Needs review), though the provided improved file ends abruptly at “Empty repo.”

This repo uses the MIT License.

The upstream MIT license and credit are preserved in UPSTREAM_LICENSE. Keep that credit when you copy, share, or change the skill.