002-monorepo-setup

name	002-monorepo-setup
description	Step-by-step instructions for setting up and scaffolding a new monorepo following the standard layout, naming conventions, Makefiles, Mise tooling, and README requirements defined in agentme-edr-301. Activate this skill when the user asks to create, initialize, or set up a monorepo, add a new application or module to an existing monorepo, or verify that a monorepo complies with the standard structure.
metadata	{"author":"flaviostutz","version":"1.0"}

Overview

Creates or extends a monorepo that follows the standard layout from agentme-edr-301: top-level application folders, independent module roots, sibling example and multi-module test areas, Mise-managed tooling, and Makefiles at every level so any contributor can build, lint, and test any part of the monorepo with a single, predictable command.

Related EDRs: agentme-edr-301, agentme-edr-502, agentme-edr-016

Instructions

Phase 1: Gather information

1. Ask for (or infer from context):
   • Applications — names and short descriptions of the top-level applications to scaffold.
   • Modules — modules inside each application (e.g., renderer, dataloader, cli).
   • Primary language(s) — Go, Python, TypeScript, etc., to choose the right build commands.
   • Tool versions — versions to pin in .mise.toml (compilers, runtimes, CLI tools).
2. Confirm the target directory (default: current workspace root).

---

Phase 2: Create root-level files

.mise.toml

Pin all required tool versions. Example for a Go + Node.js monorepo:

[tools]
go = "1.22"
node = "24"
golangci-lint = "1.57"

Root Makefile

Coordinates build, lint, and test across all applications. Also exposes a setup target.

.PHONY: all build lint test clean setup

APPS := <app1> <app2>   # replace with actual application names

all: build lint test

build:
	$(foreach app,$(APPS),$(MAKE) -C $(app) build &&) true

lint:
	$(foreach app,$(APPS),$(MAKE) -C $(app) lint &&) true

test:
	$(foreach app,$(APPS),$(MAKE) -C $(app) test &&) true

clean:
   $(foreach app,$(APPS),$(MAKE) -C $(app) clean &&) true
   rm -rf .cache

setup:
	@echo "Install Mise: https://mise.jdx.dev/getting-started.html"
	@echo "Then run: mise install"
	@echo "See README.md for full setup instructions."

Root .gitignore

Must ignore shared artifact and cache folders:

dist/
.cache/

Root README.md

Must include four sections:

# <Monorepo Name>

## Overview
<What this monorepo contains and its high-level structure.>

## Machine setup
1. Install [Mise](https://mise.jdx.dev/getting-started.html).
2. Clone the repository and run `mise install`.
3. <Any OS-level prerequisites.>

## Quickstart
<Instructions to run at least one project locally as a concrete working example.>

## Repository map
| Folder              | Description                        |
|---------------------|------------------------------------|
| `shared/`           | Libraries and scripts shared across all apps |
| `<app1>/`           | <Short description of app1>        |
| `<app2>/`           | <Short description of app2>        |

Root CONTRIBUTING.md

Must explain the contribution workflow in a short, explicit way.

# Contributing

## Bugs
Report bugs in GitHub issues with steps to reproduce, expected behavior, and actual behavior.

## Features
Discuss feature ideas in an issue before opening a pull request so scope and approach can be agreed first.

## Pull requests
Submit fixes and features through pull requests from feature branches targeting `main`.

## Review etiquette
Use [Conventional Comments](https://conventionalcomments.org/) in review feedback.

## Keep changes focused
Keep pull requests small and focused enough that review and discussion stay efficient.

---

Phase 3: Create the shared/ area

shared/
├── libs/       # Reusable libraries consumed by applications
└── scripts/    # Build/CI/dev scripts used across applications

Create these folders; populate only if shared content already exists.

---

Phase 4: Scaffold each application

For each application:

1. Create the application folder using lowercase, hyphen-separated names (e.g., graph-visualizer).

2. Create <app>/README.md with the four required sections:

   # <Application Name>
   
   ## Purpose
   <What this application does and why it exists.>
   
   ## Architecture overview
   | Module        | Description                        |
   |---------------|------------------------------------|
   | `<module1>/`  | <What it does and what it produces>|
   
   ## How to build
   Run `make build` from this folder or from the repository root.
   
   ## How to run
   <Minimal working example.>
   

3. Create <app>/Makefile that delegates to each module:

   .PHONY: all build lint test clean
   
   MODULES := <module1> <module2>   # replace with actual module names
   
   all: build lint test
   
   build:
   	$(foreach mod,$(MODULES),$(MAKE) -C $(mod) build &&) true
   
   lint:
   	$(foreach mod,$(MODULES),$(MAKE) -C $(mod) lint &&) true
   
   test:
   	$(foreach mod,$(MODULES),$(MAKE) -C $(mod) test &&) true
   
   clean:
   	$(foreach mod,$(MODULES),$(MAKE) -C $(mod) clean &&) true
   	rm -rf .cache
   

4. Create <app>/shared/ — leave empty if no cross-module shared code exists yet.

5. Create sibling aggregation folders when needed: <app>/examples/, <app>/tests_integration/, and <app>/tests_benchmark/ for artifacts that apply to multiple modules.

---

Phase 5: Scaffold each module

For each module inside an application:

1. Create the module folder using lowercase, hyphen-separated names (e.g., data-loader).

2. Create <app>/<module>/README.md with consumer usage first and short developer commands at the end.

3. Create <app>/<module>/Makefile with the common targets, adapted to the module's language. Redirect persistent caches into .cache/ and write distributable artifacts to dist/.

   Go:

   .PHONY: all build lint test clean
   
   all: build lint test
   
   build:
   mise exec -- go build ./...
   
   lint:
   mise exec -- golangci-lint run ./...
   
   test:
   mise exec -- go test ./... -cover
   
   clean:
    rm -rf dist .cache
   

   Node.js / TypeScript:

   .PHONY: all build lint test clean
   
   all: build lint test
   
   build:
   mise exec -- pnpm exec tsc --project tsconfig.json
   
   lint:
   mise exec -- pnpm exec eslint ./src
   
   test:
   mise exec -- pnpm exec jest --verbose
   
   clean:
    rm -rf dist .cache
   

   Python:

   .PHONY: all build lint test clean
   
   all: build lint test
   
   build:
   mise exec -- uv build --project . --out-dir dist
   
   lint:
   mise exec -- uv run --project . ruff check .
   
   test:
   mise exec -- uv run --project . pytest
   
   clean:
    rm -rf dist .cache
   

4. Add source files appropriate to the language, placing them inside the module folder.

5. Place module-specific integration tests and benchmarks predictably: <module>/tests_integration/ and <module>/tests_benchmark/ when they are not co-located by language convention.

---

Phase 6: Verify and report

After scaffolding, run the following checks and fix any issues:

• make build at the repository root succeeds.
• make lint at the repository root passes.
• make test at the repository root passes.
• All folder and file names are lowercase and use hyphens.
• The root .gitignore ignores dist/ and .cache/.
• A CONTRIBUTING.md exists at the repository root and covers bugs, feature discussions, pull requests, Conventional Comments, and small focused changes.
• Every application folder has a README.md covering all four required sections.
• Every module folder has a README.md, Makefile, dist/ location, and .cache/ strategy.
• A .mise.toml exists at the repository root with all required tool versions pinned.

---

Examples

Example: adding a new pcb-devices application with a firmware module (Go)

pcb-devices/
├── README.md
├── Makefile
├── examples/
├── shared/
└── firmware/
   ├── README.md
    └── Makefile

pcb-devices/Makefile:

.PHONY: build lint test
MODULES := firmware
build:
	$(foreach mod,$(MODULES),$(MAKE) -C $(mod) build &&) true
lint:
	$(foreach mod,$(MODULES),$(MAKE) -C $(mod) lint &&) true
test:
	$(foreach mod,$(MODULES),$(MAKE) -C $(mod) test &&) true

pcb-devices/firmware/Makefile:

.PHONY: build lint test
build:
	go build ./...
lint:
	golangci-lint run ./...
test:
	go test ./... -cover

---

Edge Cases

• Cross-application dependency requested: Refuse and suggest publishing the shared code as a library in shared/libs/ instead.
• Module with no compilable output (e.g., pure scripts): Still create the Makefile; build can be a no-op (@true) but the target must exist.
• Language not listed above: Mirror the pattern — build produces an artifact, lint runs static analysis, test runs tests. Adapt commands to the actual toolchain.
• Existing files: Never overwrite existing README.md, CONTRIBUTING.md, or Makefile files without user confirmation. Diff and propose additions instead.