ToolJet

# MISSION: Scaffold "ToolJet" 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 **ToolJet**.
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## 1. PROJECT SPECIFICATIONS & BENCHMARK
- **Reference Architecture**: ToolJet
- **What It Does**: Open-source low-code application platform for building enterprise internal tools, business workflows, and AI agents.
- **Domain & Category**: Low-Code Developer Tool Platform
- **Production Scale**: 6-20 people
- **Development Mode**: HYBRID
- **Architectural Rationale**: ToolJet allows teams to build complex internal web applications and dashboards with drag-and-drop React UI components and 50+ data connectors.
- **Live Website Reference**: https://tooljet.com
- **Source Repository**: https://github.com/ToolJet/ToolJet
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## 2. PRODUCTION TECH STACK
- **Full Stack Array**: JavaScript, TypeScript, React, NestJS, PostgreSQL, Redis, Tailwind CSS, Docker
- **Primary Language(s)**: JavaScript, TypeScript, SCSS, Dockerfile, Shell, Handlebars
- **License of the reference repo**: AGPL-3.0
- **Frontend**: React — Visual drag-and-drop app builder and reactive component rendering engine; Tailwind CSS — Utility styling foundation for dashboard layouts and customizable UI widgets; TypeScript — Type-safe architecture across frontend state models and builder controls
- **Backend & APIs**: JavaScript — Dynamic query transformation runtime and sandboxed client script evaluator; NestJS — Enterprise backend application framework organizing services, auth, and workers
- **Data & persistence**: PostgreSQL — Relational system database and ToolJet DB internal data persistence layer; Redis — In-memory cache and queue broker powering BullMQ background jobs and events
- **Infrastructure & deploy**: Docker — Multi-service container definitions orchestrating app server, PostgREST, and Redis
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## 3. KEY ARCHITECTURAL DECISIONS (audited from https://github.com/ToolJet/ToolJet @ 7f406ab)
1. **Sandboxed JavaScript Execution via isolated-vm**: Executes custom user-provided JavaScript expressions securely inside V8 isolates to prevent unauthorized system and process access.
2. **Built-in ToolJet DB via PostgREST Integration**: Embeds a managed PostgreSQL schema exposed over HTTP via PostgREST, providing out-of-the-box relational tables without external database setup.
3. **Pluggable Marketplace Connector Architecture**: Isolates data source integrations into modular Lerna packages under plugins/ and marketplace/, decoupling vendor SDK dependencies.
4. **Realtime Canvas Collaboration with Yjs**: Synchronizes visual canvas modifications and multi-user cursor presences using Yjs CRDTs over persistent WebSockets.
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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**:
   - Isolate interactive UI state to leaf components. Keep core pages lightweight and performant.
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 (PostgreSQL, Redis): 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.