technicalArchitecture

Technical Architecture

System Overview

Catalyst employs a microservices architecture organized into distinct application layers, each with specific responsibilities and clear interfaces. This separation enables independent scaling, isolated testing, and flexibility in technology choices while maintaining system coherence through well-defined APIs.

Architecture Layers

Application Layer

Three Next.js 14 web applications, each optimized for its user audience:

  • Investor Dashboard: Portfolio tracking, opportunity discovery, and multi-currency wallet management
  • SME Portal: Mobile-responsive funding request creation and profit reporting
  • Admin Platform: Operational dashboards with data visualization and monitoring tools

All applications communicate with the backend exclusively through RESTful HTTP requests, maintaining clean separation between presentation logic and business logic.

Backend API Layer

Node.js Express application providing unified business logic for all platform operations:

  • Authentication via JWT tokens
  • Authorization through middleware
  • Database transactions via Prisma ORM
  • Blockchain coordination through Blockfrost API
  • External service integrations (exchange rates, file uploads)

The API implements RESTful principles with resource-based routing, standard HTTP methods, JSON request/response formats, and meaningful status codes.

Database Layer

PostgreSQL for persistent storage with Prisma ORM providing type-safe database access and automated migration management. The schema implements:

  • Relational data modeling with foreign key constraints
  • Indexes on frequently queried fields
  • Transaction support for multi-table updates
  • Financial amounts stored as BigInt in smallest currency units

Blockchain Layer

Integration with Cardano’s preprod testnet (mainnet planned) through Blockfrost API. Smart contracts written in Aiken implement investment escrow logic:

  • Funds lock on-chain until predefined conditions trigger release
  • Users interact through client-side wallet applications (Nami, Eternl, Flint)
  • Never exposing private keys to the platform
  • Maintaining self-custody while participating in the ecosystem

External Services

  • CoinGecko: Real-time ADA/NGN exchange rates
  • ExchangeRate-API: Fiat currency conversions (USDM/USD/NGN)
  • Cloudinary: File uploads with automatic optimization and secure CDN delivery

Technology Stack

Backend:

  • Node.js 18 LTS
  • Express 4.18
  • Prisma 5.x (ORM)
  • PostgreSQL 14+
  • JWT & bcrypt
  • TypeScript 5.x

Frontend:

  • Next.js 14
  • React 18
  • TypeScript 5.x
  • Tailwind CSS 3.x
  • Lucid Cardano
  • Axios

Blockchain:

  • Cardano
  • Aiken 1.0
  • Plutus
  • Blockfrost
  • Lucid 0.10

Infrastructure:

  • Vercel (frontend)
  • Railway/AWS (backend)
  • PostgreSQL managed instance
  • Cloudinary (CDN)
  • GitHub Actions (CI/CD)

Why This Stack?

  • TypeScript across all layers for compile-time error detection
  • Next.js provides SSR, code splitting, and optimized builds
  • Prisma generates type-safe database clients, reducing runtime errors
  • Cardano offers formal verification, low fees ($0.20), and sustainability
  • Fast feedback loops and high confidence in code correctness
APIBlockchain