/monorepo

description:  >
  Create an initial Claude Code setup for a brownfield project with monorepo topology
  (including hybrid submodular configurations).
disable-model-invocation: true
user-invocable: true

Claude Code Monorepo Scaffolding

Your goal is to create an initial setup for Claude Code in a large pre-existing monorepo project, including agent instructions and context information. You work in close collaboration with the user to obtain the required base knowledge about the goals and structure of the project as well as each sub-project.

**Additional user arguments**: $ARGUMENTS

**Language hint**: Always create all generated document content in English for consistency across the codebase, while continuing to speak to the user in the language of their choice.

**Platform hint**: Instructions and templates assume a Linux host with GNU coreutils. Adapt to the detected user OS.

• macOS — Substitute BSD equivalents for GNU-only utilities.
• Windows — Still use `.sh` files (skip irrelevant `chmod +x`), assuming Git Bash is available at runtime.

Highlight this requirement in the Debriefing. Set `"shell": "bash"` on command hooks in `settings.json`. Omit the entire `sandbox` block from `settings.json` as long as bash sandboxing is unsupported.

Agent Content Principles

When generating content for `.md` files below, you are writing prompts and context for other AI coding agents. Follow these principles to optimally tailor your instructions to their needs:

• **Concise** — Minimize token usage. Prefer keywords and telegraphic phrasing over full prose.
• **Structured** — Use compact Markdown to delineate connected aspects.
• **Actionable** — Generate concrete operational directives, as abstract guidelines may lead to over-refusal or handwaving.

Avoid aspirational quality statements, general engineering practices, blanket prohibitions.

• **Referential** — Provide pointers to key code files the agents can read themselves.

Do not describe how code works in agent instructions as such duplication leads to drift.

• **Scoped** — Context is hierarchical. The central CLAUDE.md applies to every scope and must only

contain core project identity and semantics. Sub-project CLAUDE.md, rules and agent instructions progressively disclose domain- and task-specific knowledge.

• **Durable** — Only include details that remain invariant under normal codebase evolution.

Reference namespaces or search terms instead of single artifacts.

Workflow

Begin execution by creating a formal task list for progress tracking using the `TaskCreate` tool (if available). Create a task for each of the following phases (##) and sub-phases (###). This protects you from accidentally skipping phases and visualizes the progress for the user.

Phase 1: Reconnaissance

1. Use `Explore` agents to scan the repository and build an initial understanding of its structure

• Top-level directory content that hints at used technologies (e.g. `package.json`, `composer.json`, `Cargo.toml`, `go.mod`, `Makefile`, `Dockerfile`)
• Existing documentation (e.g. `README.md`, `CONTRIBUTING.md` or `docs/`)
• Style (e.g. imperative mood) and common patterns (e.g. ticket numbers) in commit messages from the `git log`.

2. Read any discovered documentation and technology manifest files 3. Check for an existing `CLAUDE.md` or `.claude/` directory — if found, establish if the user wants to amend or replace these. 4. Summarize your findings and conclusions briefly for the user and ask if they want to comment or add information.

Phase 2: User Interview

Interview the user to establish the project's base details and sub-project boundaries. Use `AskUserQuestion` where appropriate to keep the conversation structured.

Offer pre-defined choice options if likely answers to a question are already known from context. However, **never skip parts of the interview** even if all answers could be inferred. The purpose of the interview is to include tribal project knowledge not captured by reconnaissance.

General Question Catalogue

1. What is the name of the project? 2. Who is the project creator and/or maintainer (company/organization)? 3. What is the overall purpose of the project (one-sentence summary)? 4. What is the production scale of the project (data size, number of users)? 5. What is the general technological approach of the project (one-sentence summary)? 6. What are key concepts or vocabulary that every developer needs to learn on their first day (independent of sub-project)? 7. What sub-projects or applications exist in this monorepo?

Sub-Project Question Catalogue

Go through **every** sub-project established in general question 7 and repeat these questions for each of them.

1. What is the name of the sub-project or the development team (e.g. "backend" / "frontend")? (If the name is more than one word, also establish a short slug to use in generated files.) 2. What are the main purposes / functions of the sub-project? 3. What are key terms or vocabulary that every developer in this sub-project needs to know? 4. What are the main technologies used (programming language, framework, deployment...)? 5. Does this sub-project live under a **dedicated root directory**?

• If **yes**: what is the path to that directory relative to the project root?
• If **no**: what file/path glob pattern uniquely identifies its source files? (e.g. `src/Payments/**/*.ts`)

This is typically `<namespace-path>/**/*.<language-extension>`. 6. What are the key source directories? 7. How are automated tests organized and run? 8. Are there tools for linting or other automated code quality control?

Phase 3: Generate Artifacts

3a — Claude Code Settings

1. Copy the [settings template](./templates/settings-template.json) to `<project-dir>/.claude/settings.json` 2. Copy the [statusline template](.