Medusa

# MISSION: Scaffold "Medusa" Production Architecture
You are an expert Senior Staff Software Architect and Full-Stack Engineer. Your mission is to scaffold and implement a production-grade, highly reliable, and modular codebase following the proven architecture of **Medusa**.
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## 1. PROJECT SPECIFICATIONS & BENCHMARK
- **Reference Architecture**: Medusa
- **What It Does**: Medusa is an open-source commerce platform: a Node.js and TypeScript server (packages/medusa, packages/core/framework) persisting to PostgreSQL via MikroORM and wired together with the Awilix DI container, plus a bundled React admin dashboard.
- **Domain & Category**: E-commerce API
- **Production Scale**: 20+ people
- **Development Mode**: CLASSIC
- **Architectural Rationale**: Splitting commerce logic into independently versioned @medusajs packages, backed by a pluggable workflow engine (in-memory for development, Redis and BullMQ for production), lets teams customize or replace individual modules without forking the whole platform.
- **Live Website Reference**: https://medusajs.com
- **Source Repository**: https://github.com/medusajs/medusa
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## 2. PRODUCTION TECH STACK
- **Full Stack Array**: TypeScript, Node.js, React, PostgreSQL, Redis, MikroORM, Vite
- **Primary Language(s)**: TypeScript, JavaScript
- **License of the reference repo**: NOASSERTION
- **Frontend**: React — Renders the admin dashboard (packages/admin/dashboard) bundled with every Medusa install.; Vite — Dev server and preview build for the admin dashboard; production bundling uses tsup.; React Router — Client-side routing for the admin dashboard single-page app.; Radix UI — Headless component primitives underlying the admin dashboard UI kit.; TanStack Query — Data fetching and caching layer for the admin dashboard against the Medusa API.; TanStack Table — Powers sortable, paginated data tables in the admin dashboard.; i18next — Localizes admin dashboard UI strings across supported languages.
- **Backend & APIs**: Node.js — Runs the core commerce server built from packages/medusa and packages/core/framework.; MikroORM — Maps commerce entities to PostgreSQL and drives schema migrations via the medusa-mikro-orm CLI.; PostgreSQL — Primary datastore, accessed through the pg driver bundled in the shared deps package.; Awilix — Dependency-injection container that wires modules and services together at runtime.; Zod — Validates workflow and module input schemas across the framework package.; BullMQ — Backs the Redis-based workflow engine module that persists and retries long-running workflow steps.; Redis — Queue store for the ioredis-backed workflow engine module used to make workflows durable.
- **Infrastructure & deploy**: Turborepo — Orchestrates build and test pipelines across the yarn workspace packages.; Yarn — Workspace package manager for the root and www monorepo workspaces.; Algolia — Optional search backend wired through the instantsearch-adapter package for storefront search.
- **Tooling, testing & ops**: Jest — Unit and integration test runner used across packages and integration-tests/.; Claude Code — Repo ships Claude Code skill, agent, and command configs plus CLAUDE.md and memory/MEMORY.md.; GitHub Actions — Runs docs automation, OpenAPI checks, admin i18n validation, and release workflows.
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## 3. KEY ARCHITECTURAL DECISIONS (audited from https://github.com/medusajs/medusa @ c000d37)
1. **Admin dashboard ships as a separate React SPA package**: packages/admin/dashboard is its own workspace package built with Vite and tsup rather than living inside packages/medusa, so the API server and the admin UI can be versioned, built, and deployed independently.
2. **Dependency injection replaces manual service wiring**: packages/deps/package.json bundles awilix as the DI container that packages/core/framework uses to resolve modules and services, so commerce modules are registered and injected rather than imported and instantiated directly.
3. **Workflows persist through a pluggable orchestration engine**: packages/core/workflows-sdk defines the workflow composer, and two interchangeable engine modules implement it: packages/modules/workflow-engine-inmemory for development and packages/modules/workflow-engine-redis (bullmq plus ioredis) for durable, retryable production workflows.
4. **PostgreSQL and MikroORM are fixed data-layer choices**: packages/deps/package.json pins @mikro-orm/postgresql, @mikro-orm/knex, and pg as direct dependencies consumed by packages/core/framework, so every Medusa module persists through the same ORM and database engine rather than choosing its own.
5. **Commerce logic is split into independently publishable modules**: packages/modules/* (for example api-key, workflow-engine-redis) and packages/core/* (core-flows, orchestration, query) are separate npm packages under the @medusajs scope, each with its own package.json, so modules can be depended on individually outside the core server.
6. **A CLI scaffolds new projects instead of a template repo**: packages/cli/create-medusa-app is a published npm package (create-medusa-app) that uses inquirer, boxen, and wait-on to interactively scaffold a new Medusa application, similar to create-react-app rather than a git-cloned starter.
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## 4. NON-NEGOTIABLE ARCHITECTURAL GUARDRAILS
1. **Monorepo & Modular Separation**:
   - Structure as a Turborepo monorepo with strict package boundaries:
     - `apps/web`: Application UI, routing, layouts, and server endpoints.
     - `packages/ui`: Shared design tokens, CSS variables, and Radix UI primitive components.
     - `packages/db`: Database schemas, client singleton, declarative migrations, and seed scripts.
     - `packages/config`: Shared TypeScript, ESLint, and build configurations.
2. **Strict Type Safety & Zero `any` Policy**:
   - Enable `strict: true`, `noImplicitAny: true`, and `strictNullChecks: true`.
   - Validate ALL external inputs, API request bodies, and query parameters with **Zod** schemas before execution.
3. **Frontend & Rendering Guidelines**:
   - Utilize Vite 6 with TanStack Router for fully type-safe routing. Manage server state and caching via TanStack Query v5 with optimistic UI updates.
4. **Design System & Aesthetics**:
   - Keep every color, radius, shadow and font in a single token file (CSS variables) and consume tokens everywhere; never hardcode hex values in components.
   - Prefer crisp 1px borders and one subtle shadow scale over blurry default shadows. Pair one sans-serif for body/headings with one monospace for tags, badges, metrics, and code.
5. **Data Layer & Reliability**:
   - Write declarative schema definitions with foreign keys, composite indexes on queried filters, and automated timestamp triggers.
   - Use connection pooling and prepared statements for serverless database execution.
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## 5. STEP-BY-STEP SCAFFOLDING ROADMAP
- **Phase 1: Workspace & Root Config**: Initialize package manager, monorepo configuration (`turbo.json`, `tsconfig.base.json`, `package.json`).
- **Phase 2: Database Schema & Client**: Set up the data layer: client, connection pool, models, and migration scripts.
- **Phase 3: Design Tokens & UI Primitives**: Build accessible `Button`, `Input`, `Card`, `Badge`, and layout wrappers inside `packages/ui`.
- **Phase 4: Core Application Routes & Handlers**: Implement primary authentication, user session handling, and application routes.
- **Phase 5: Quality Assurance & Build Verification**: Run `tsc --noEmit`, ESLint, Prettier, and smoke test suites to ensure zero compilation or runtime errors.
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## 6. EXECUTION INSTRUCTIONS
1. Review all specifications, architectural guardrails, and stack choices above.
2. Present the full monorepo directory tree structure.
3. Systematically generate the complete, production-ready codebase according to the 5-phase roadmap above — starting with the root workspace setup, followed by the database schema, UI design system package, and full-stack application routes until the repository is fully scaffolded and ready to run.