API Development and Integrations
Typed, documented, observable APIs that let your systems actually talk to each other.
· Reviewed by senior engineers
01 What it is
What this service is
API development and integrations is the engineering work that lets your systems share data and behaviour cleanly — both the APIs you expose to your own frontend, partners, and customers, and the integrations you build to consume third-party services like Stripe, NetSuite, Salesforce, Shopify, SAP, or HMRC's Making Tax Digital endpoints. It is the connective tissue of a modern business.
We design APIs the way good APIs are designed: typed end-to-end (OpenAPI, GraphQL SDL, or protobuf), versioned with clear deprecation policies, paginated and idempotent where it matters, and instrumented so every request has a trace. We document them in a way that an external partner can integrate without filing a ticket — clear request and response examples, error catalogues, sandbox credentials, and a Postman or Insomnia collection generated from the schema.
Integrations are the inverse: consuming APIs that often were not designed as cleanly. We build adapters that absorb the quirks — retries, exponential backoff, circuit breakers, dead-letter queues — so your application code stays clean and your operations team has the dashboards to see what is happening.
02 What it's for
What it's for
APIs and integrations are for any business whose systems do not all live in one box. A US healthcare startup integrating EHR data through HL7 FHIR with HIPAA-compliant logging; a UK retailer connecting Shopify to Microsoft Dynamics with three-way inventory sync; a LATAM marketplace integrating MercadoPago, PIX, and OXXO alongside Stripe for cross-border settlements; a B2B SaaS shipping a public API as a product so customers can build on top.
They are also the right call when your team is spending more time on glue code than on the differentiated product. If your engineers are debugging Salesforce field mappings every Tuesday, a well-designed integration layer recovers that time. If your partners complain that your API is hard to use, the cost is usually a missed deal somewhere.
We work with teams from Series A startups exposing their first public API through to enterprises with hundreds of internal services that need an API gateway, a developer portal, and a sensible deprecation cadence.
03 How to use it
How to engage devinsta
We begin with a contract-first workshop. Before any code is written, we agree on the resource model, the verbs, the error structure, and the versioning policy. The output is an OpenAPI or GraphQL schema your team signs off on. This sounds slow and it saves months downstream.
From there we build in sprints, with each sprint producing a working endpoint deployed to a sandbox, complete with documentation generated from the schema. Your team gets early access; partners get sandbox credentials by week three; production launch usually follows in eight to twelve weeks for a focused API surface.
For integrations we run a similar pattern: one integration at a time, end-to-end, with monitoring before we move to the next. We have learned the hard way that shipping six half-finished integrations is much worse than two solid ones.
04 How to deploy
How we deploy it
APIs are deployed behind a gateway — typically AWS API Gateway, Kong, or Apollo Router for GraphQL — with rate limiting, authentication, and request validation enforced at the edge. The application logic runs on Fargate, Cloud Run, or Lambda depending on traffic profile and cold-start sensitivity.
Authentication is OAuth 2.1 or JWT with rotating signing keys; for partner APIs we issue scoped API keys with per-client rate limits and usage dashboards. Webhook delivery is asynchronous through SQS, SNS, or EventBridge with idempotency keys, exponential backoff, and a dead-letter queue every consumer can introspect. Failed webhooks are replayable from a queue console without needing to redeploy anything.
Observability is non-negotiable. Every request gets a correlation ID propagated across services, captured in Datadog APM or Honeycomb, and tied back to the originating user or partner. We set SLOs on latency and error rate per endpoint, alert on burn-rate breaches, and produce a monthly partner-facing status report. For regulated workloads we maintain a separate audit log in an immutable store (S3 with Object Lock or a WORM-mode database) and document the data residency posture for GDPR, HIPAA, or PCI DSS as required.
05 What we provide
What you get from us
- Contract-first OpenAPI, GraphQL, or gRPC schema with versioning policy
- Production-grade implementation in Node, Go, or Python with full type coverage
- Authentication, rate limiting, and quota management at the API gateway
- Webhook delivery infrastructure with retries, dead-letter queues, and replay tooling
- Auto-generated developer documentation, SDKs (TypeScript, Python), and Postman collections
- Integration adapters for Stripe, Shopify, NetSuite, Salesforce, SAP, HubSpot, and others
- Observability with OpenTelemetry, SLO dashboards, and per-endpoint alerting
- Partner onboarding playbook and sandbox environment with seed data
FAQ
Common questions
REST, GraphQL, or gRPC — which should we pick?
It depends on the consumer. Public partner APIs are almost always REST with OpenAPI because tooling is universal. Internal service-to-service traffic where performance matters tends to be gRPC. GraphQL shines when one frontend needs to aggregate many backend services and benefits from a typed contract. We help you pick based on who consumes the API and how often it changes.
How do you handle versioning and breaking changes?
We version URL paths for major breaking changes (/v1, /v2) and use additive evolution for minor changes. Deprecation is announced six months in advance, communicated through the developer portal, and surfaced in response headers. We do not break partners without warning.
Can you integrate with our legacy ERP or accounting system?
Yes. We have built integrations with SAP, Oracle NetSuite, Microsoft Dynamics, Sage, Xero, QuickBooks, and various bespoke mainframes accessed over SOAP or even SFTP file drops. We absorb the legacy quirks in an adapter so your modern application code does not have to know.
Do you build webhooks or just consume them?
Both. We design idempotent, signed, retried webhook delivery for APIs you expose, and we build resilient webhook consumers for APIs you receive. The hard parts — replay, deduplication, ordering guarantees, dead-letter handling — are part of the deliverable, not an afterthought.