API & systems integration
We design APIs that other teams can build on, and we connect systems that were never meant to talk to each other. Payments, messaging, third-party services, and the syncs between them, built to survive the days when something is down.
What we do
- REST API design with versioning, pagination, and documentation written alongside the code.
- Payment integrations: charges, subscriptions, refunds, and reconciliation.
- Messaging and queues with RabbitMQ, for work that should not run inside a request.
- Third-party service integration: CRMs, accounting, logistics, and identity providers.
- Webhooks and scheduled syncs with retries, idempotency, and an audit trail.
How we work
Integrations fail at the seams: a partner times out, a webhook arrives twice, a field changes without notice. We design for that from the start, with idempotent handlers, retries and backoff, dead letter queues, and logging that shows exactly what was sent and received. The contract is written in OpenAPI before the endpoints exist, so both sides can build in parallel.
Stack
Laravel and Node.js services, OpenAPI for contracts, REST and webhooks over HTTP, RabbitMQ and Redis queues for asynchronous work, OAuth 2.0 for access between systems.
Questions we hear
Do we get documentation with the API?
Yes. We write the contract in OpenAPI first and keep it in the repository next to the code, so documentation and endpoints change in the same commit. Your team gets a browsable reference with example requests, not a description written months after the fact.
What happens when a third-party service is unreliable?
We assume it will be. Outbound calls get timeouts, retries with backoff, and a queue behind them, so a slow partner never blocks your users. If a service stays down, the work waits in a dead letter queue and resumes instead of disappearing.
How do you handle API versions?
Additive changes ship without a new version. Breaking changes get a new version, a migration note, and a deprecation window agreed with whoever depends on the old one, which stays available until they have moved.
Have a project in mind? Write to hello@longisoft.com