Nextcloud

# MISSION: Scaffold "Nextcloud" 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 **Nextcloud**.
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## 1. PROJECT SPECIFICATIONS & BENCHMARK
- **Reference Architecture**: Nextcloud
- **What It Does**: Nextcloud server is a self-hostable PHP 8.3 platform for file storage, sharing, and collaboration, exposing a stable OCP public API to first-class PHP apps and a Vue frontend that is transitioning from Webpack/Vue 2 to Vite/Vue 3.
- **Domain & Category**: Self-Hosted Collaborative Productivity Suite
- **Production Scale**: 20+ people
- **Development Mode**: CLASSIC
- **Architectural Rationale**: Server internals (OC) are kept separate from a versioned public API (OCP) so that independently namespaced apps under apps/ can extend Nextcloud without depending on private implementation details, while database support is validated per-engine in CI.
- **Live Website Reference**: https://nextcloud.com
- **Source Repository**: https://github.com/nextcloud/server
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## 2. PRODUCTION TECH STACK
- **Full Stack Array**: PHP, JavaScript, TypeScript, Vue, MySQL, PostgreSQL, SQLite, Vite, Webpack
- **Primary Language(s)**: PHP, JavaScript, TypeScript
- **License of the reference repo**: AGPL-3.0
- **Frontend**: Vue — Powers the Vue 3 UI in build/frontend and the legacy Vue 2 UI in build/frontend-legacy.; Vite — Builds the current Vue 3 frontend bundle.; Webpack — Builds the legacy Vue 2 apps and core assets that have not migrated to Vite.; Pinia — State management store used by the Vue 3 frontend.
- **Backend & APIs**: PHP — Implements the core server, apps under apps/*, and the OCP public API in lib/public.
- **Data & persistence**: MySQL — Supported production database, exercised by dedicated CI workflows.; PostgreSQL — Supported production database, exercised by dedicated CI workflows.; SQLite — Supported lightweight database for development and small instances.
- **Infrastructure & deploy**: Docker — Provides the devcontainer image used for local development.
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## 3. KEY ARCHITECTURAL DECISIONS (audited from https://github.com/nextcloud/server @ 014dc42)
1. **Server core is PHP with a PSR-4 autoloaded public API surface**: composer.json maps OCP\\ to lib/public and OC\\ to lib/private, giving apps a stable public API (OCP) while keeping server internals (OC) separate; core/ hosts framework-level controllers, migrations, and background jobs.
2. **Frontend is mid-migration from Webpack/Vue 2 to Vite/Vue 3**: build/frontend-legacy/package.json still builds Vue 2 apps with Webpack, while build/frontend/package.json builds a separate Vue 3 bundle with Vite; both are driven from build/demi.sh so old and new apps ship side by side during the transition.
3. **Apps are first-class, independently namespaced PHP modules**: The apps/ directory (files, dav, sharing, encryption, user_ldap, workflowengine, and more) each ship their own composer.json with an autoloader-suffix and psr-4 root, so bundled apps can be enabled, disabled, or replaced without touching core.
4. **Database support is verified per-engine in CI rather than assumed**: The workflow set (phpunit-mysql.yml, phpunit-pgsql.yml, phpunit-sqlite.yml, phpunit-mariadb.yml, phpunit-oci.yml, phpunit-mysql-sharding.yml) runs the PHPUnit suite against each supported database engine separately.
5. **DAV protocol support is isolated in its own app with its own autoloader**: apps/dav/composer/composer.json declares an OCA\\DAV\\ namespace rooted at apps/dav/lib, keeping CalDAV/CardDAV/WebDAV protocol handling (also covered by integration-dav.yml and integration-litmus.yml) separate from the core file storage code.
6. **Static analysis runs through Psalm and Rector, not just PHPUnit**: vendor-bin/psalm/composer.json and vendor-bin/rector/composer.json pin vimeo/psalm and rector/rector as isolated Composer bin dependencies, run via composer scripts (psalm, psalm:security, rector) referenced from build/rector.php and build/psalm-baseline.xml.
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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 (MySQL, PostgreSQL, SQLite): 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.