API design & systems integration
[Draft note for Manuel]: grounded directly in your own "engineering fingerprint" from Tech Profile (edge → gateway → domain service → events → systems of record) and the integration work already mentioned in the AI adoption service ("integrations to systems like Salesforce, SAP, and legacy systems"). Confirm this reads as a real, separate offering and not just a restatement of custom software development.
Most real systems aren't built from scratch in a vacuum — they need to talk to something that already exists: a CRM like Salesforce, an ERP like SAP, a legacy system nobody wants to touch, or another team's service. Getting that integration wrong is usually where a project actually breaks, not in the new code itself.
I design APIs and build the integration layer between systems, following the same shape that's worked across the enterprise projects I've owned: a thin edge, a gateway that handles auth/routing/rate limits, a domain service that holds the real business rules, events instead of tight point-to-point coupling between services (Kafka, RabbitMQ), and a data layer nobody queries directly. What that covers:
- API design — REST or event-driven, contract-first when a frontend or another team needs to build against it in parallel.
- Integration with existing systems (CRM, ERP, legacy platforms) without those systems' constraints leaking into the new codebase.
- Idempotent event handling, so a retried message or a duplicate webhook doesn't corrupt data.
- Documentation the next engineer can actually use, not just a contract sitting in someone's head.
This is the connective layer between systems — it pairs naturally with custom software development or legacy modernization when the new system's real complexity is in what it has to talk to, not in the new code itself.
Have a system that needs to integrate with something it doesn't control? Let's talk.

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