Backend + APIs
We build the systems behind the UI. REST APIs, GraphQL, WebSocket / SSE, background-job processing, integrations with third-party services. Our SaaS line runs ~50 production endpoints in Rails (Outsourcing, Finance) and Node/TypeScript (HRS, Logistics, Leads, CMS) — same stack we recommend.
Konkrete Ergebnisse
- REST + GraphQL APIs — versioned, documented (OpenAPI), authenticated (OAuth2, JWT, API key).
- Background-job pipelines — Sidekiq, BullMQ, Celery; cron + scheduled jobs.
- Real-time features — WebSocket, Server-Sent Events, pub/sub via Redis or Kafka.
- Third-party integrations — Stripe, SendGrid, Twilio, DocuSign, Salesforce, HubSpot, Airtable.
- Webhook handling + retry — idempotency keys, dead-letter queues, replay tooling.
- Migrations — language migrations (Rails → Go, PHP → Node), framework upgrades (Rails 5→7, Node LTS), database migrations (MySQL → Postgres).
Womit wir arbeiten
Wir wählen, was zu Ihrem Team passt — keine erzwungenen Präferenzen.
Languages
Node.js + TypeScript (deepest) · Ruby on Rails · Python (FastAPI, Django) · Go · Java/Kotlin (Spring) · Elixir/Phoenix (specialised)
Databases
PostgreSQL (default) · MySQL · MongoDB · Redis · DynamoDB · ClickHouse
Queues + jobs
Sidekiq (Ruby) · BullMQ (Node) · Celery (Python) · RabbitMQ · Kafka · AWS SQS
API patterns
REST (default) · GraphQL · tRPC · gRPC (internal RPC) · WebSocket · SSE
ORMs
Prisma (TypeScript) · ActiveRecord (Rails) · SQLAlchemy (Python) · Drizzle (TypeScript)
Testing
Vitest, Jest (Node) · RSpec, Minitest (Ruby) · pytest (Python) · Postman/Bruno + automation
So arbeiten wir
Discovery (1 week)
API contract design, data model, third-party integration mapping. Output: OpenAPI spec + ERD diagram.
Schema + scaffolding (1 week)
Database migrations, model layer, seed data, base auth. Nothing exposed to the world yet — but the foundation is testable.
Build endpoints (3-8 weeks)
Route by route, with tests. Sequence by dependency: read-only first, writes second, integrations third.
Production hardening
Rate limiting, observability, log aggregation, on-call runbooks. Postman/Bruno integration test suite for ongoing health checks.
Aus unserer eigenen Produktion
Merot Outsourcing API (Rails 7)
70+ controllers, JWT auth, Sidekiq for background jobs, Stripe + DocuSign + SendGrid integrations. Multi-product (admin / employer / employee) with role-based access.
Merot Logistics backend (Node + TS + Prisma)
Multi-tenant white-label SaaS — shipments, COD, GPS, BullMQ for background sync, Infobip SMS/WhatsApp integration.
Merot CMS (Node + TS + Prisma)
Headless content API serving merot.com + outsourcing blogs. Public read endpoints + admin write.
Engagement-Modell
Häufige Fragen — Backend + APIs
Rails vs. Node vs. Go — what do you recommend?
Default: Node + TypeScript for new projects under a 5-person team. Rails when you want maximum convention + speed-of-build for CRUD apps. Go when latency matters + your team already runs Go. We don't push a stack — we pick what fits your team.
Do you write tests?
Yes — the kind you can actually maintain. Unit tests for pure logic, integration tests for the API surface, end-to-end tests sparingly. Coverage isn't a goal; correctness is.
Database — Postgres or something else?
Postgres is the default. MySQL when you've inherited it. Mongo for genuinely document-shaped data (rare). DynamoDB / Cassandra when you've outgrown Postgres scale (very rare for most clients).
Idempotency for webhooks?
Yes — every webhook handler we write is idempotent. We assume the sender will retry (because they will). Dead-letter queue for failures, replay tool to reprocess.
Background jobs — what stack?
Sidekiq for Rails. BullMQ for Node. Celery for Python. We don't recommend reinventing — these are mature.
GraphQL or REST?
REST by default — simpler to debug, cache, and rate-limit. GraphQL when the client team specifically needs it (deeply nested reads with strict typing). We won't push GraphQL just to have it.
How do you handle long-running operations?
Background job with status polling endpoint, or webhook callback when complete. We avoid keeping HTTP requests open longer than 30 seconds.
What about gRPC?
Used internally between services where latency matters (e.g. our PDF service does gRPC under high load). Rarely exposed externally — REST is friendlier for clients.
Backend + APIs-Projekt scopen
60 Min. Discovery-Call kostenlos. 6-seitiger Plan in 48 h.