I design and build NestJS/TypeScript backends for SaaS products with complex permissions, data workflows, and external integrations. The delivery includes the API, PostgreSQL data model, background jobs, and documentation your team needs to run and extend it.

WHAT'S INCLUDED

• Architecture and API contracts: Map product flows into NestJS modules, service boundaries, validated request DTOs, and documented endpoints. Define authentication, permissions, pagination, and consistent error responses.

• PostgreSQL and TypeORM: Design entities, relationships, constraints, indexes, and versioned migrations. Use transactions for operations that must succeed together and review queries for excessive reads and N+1 behavior.

• Redis and BullMQ workers: Move email dispatch, document generation, AI requests, and other slow operations out of the request cycle. Configure bounded concurrency, retries with backoff, job status tracking, and failure recovery.

• External integrations: Connect PayPal, Mailgun, OpenAI, or your existing providers through dedicated adapters. Handle credentials, timeouts, rate limits, webhook verification, and duplicate events.

• Error handling and visibility: Add consistent exception responses, structured logs, request identifiers, and health checks so failures can be traced across API requests and workers.

• Verification and handover: Test critical business flows and integration failure paths. Deliver source code, migrations, Swagger documentation, an environment configuration guide, and deployment notes.

DELIVERY ESTIMATE

Typically 3 to 6 weeks for a defined backend release. I start with an architecture review and implementation plan, then deliver reviewable milestones. Existing-system migrations, complex permissions, and additional integrations are estimated separately.

Relevant project experience My backend work includes GridIronGC’s player-conversion pipeline, OriginSustain’s multi-tenant ESG reporting workflow, and Gabriel SGO’s donation and school-allocation flows. The linked examples show the product context behind these systems.

To start, send your core workflows, existing repository or API documentation, and the release you need to ship. I will define the scope, dependencies, and milestones before implementation.