TypeScript monorepos in fintech

At Pangea, we're using an Nx monorepo to manage our FX and payments platform. The monorepo approach has been transformative for code sharing, type safety, and developer experience.

Why Monorepo for Fintech?

Financial services require tight integration between services. A monorepo allows us to:

• Share types across services (critical for API contracts)
• Enforce consistent patterns
• Make refactoring safer across service boundaries
• Improve developer experience with shared tooling

The Nx Advantage

Nx provides:

• Dependency graph visualization
• Affected project detection
• Caching for faster builds
• Code generation for consistency

Type Safety Across Services

// Shared types package
export interface PaymentRequest {
  amount: Decimal;
  currency: CurrencyCode;
  recipientId: string;
}

// Used in both API and worker services
import { PaymentRequest } from '@pangea/shared-types';

This ensures that changes to payment types are caught at compile time across all services.

Challenges

• Build times can grow
• Need discipline around dependencies
• CI/CD complexity increases
• Requires team buy-in

Best Practices

1. Keep shared code in dedicated packages
2. Use strict dependency rules
3. Invest in CI/CD optimization
4. Document the monorepo structure
5. Regular dependency audits

The monorepo has been a game-changer for maintaining consistency and type safety across our platform.