API Development & System Integration
Documented APIs and integration layers that keep your systems consistent without manual re-entry.
What this is
Integration work fails on the unglamorous parts: retries, idempotency, partial failure and reconciliation. We build integrations that assume the network will fail and the other system will change, so a retry cannot duplicate an order and a mismatch is surfaced rather than silently absorbed.
When teams call us about this
If more than one of these is familiar, there is usually a case worth scoping.
- The same record is typed into two systems because they do not talk.
- A nightly export breaks silently and nobody notices for a week.
- Partners ask for API access and there is no documented API to give them.
- A retry created duplicate orders and reconciliation found it a month later.
What this covers
Each item below is part of this service line. Where an offering needs a specialist partner, it is marked as such rather than implied.
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API development
REST and GraphQL APIs with specifications, versioning and sandbox access.
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System integration
Reliable data flow between CRM, ERP, finance, commerce and bespoke systems.
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Third-party integration
Payment, logistics, communication, mapping and identity provider integration.
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Legacy bridges
Database, file or scripted integration where no API exists.
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Event-driven architecture
Queues, webhooks and event streams with ordering and replay handling.
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Data synchronisation
Two-way sync with conflict rules and reconciliation reporting.
What you receive
Artefacts that end up in your repositories and your cloud account, not locked inside our team.
- Documented API with an OpenAPI specification and versioning policy
- Authentication, authorisation, rate limiting and quota handling
- Integration layer with idempotency, retries and backoff
- Webhook delivery with signing, retry and replay
- Reconciliation job surfacing mismatches rather than hiding them
- Monitoring, alerting and a dead letter queue for failed messages
- Sandbox environment and integration documentation for consumers
Typical engagements
The shapes of work we are asked for most often in this area.
Store to back office
Keeps orders, stock and customers consistent between commerce and ERP.
CRM and finance sync
Stops the same customer and invoice data being maintained twice.
Partner API
Gives integrators a documented, versioned, rate-limited interface.
Replacing fragile exports
Turns a brittle nightly file transfer into monitored, event-driven integration.
How we run it
Discovery
Systems, data ownership, volumes, failure modes and reconciliation requirements.
Contract design
Schemas, specification, versioning and error semantics agreed before build.
Build
Integration with idempotency, retries, backoff and dead letter handling.
Testing
Contract tests, partial failure simulation and load testing at realistic volume.
Deployment
Staged rollout with monitoring, alerting and reconciliation running from day one.
Documentation
Consumer documentation, sandbox access and an operational runbook.
Products we built and sold
Our own commercial platforms, built with this engineering stack. These are products, not client references.
RideOn
A ride-hailing and fleet management platform, now with agentic dispatch, driver support and demand intelligence.
View product Multivendor marketplaceUniBooker
A configurable multivendor service-booking marketplace with agentic onboarding, matching and support.
View product Classifieds marketplaceClassify
A classifieds marketplace with agentic listing creation, moderation and buyer-seller matching.
View productAPI Development & System Integration — FAQs
Including the questions where the honest answer is "it depends", and what it depends on.
REST or GraphQL?
REST for straightforward resource access and partner-facing APIs, GraphQL where clients need varied shapes of the same data. We pick per interface rather than standardising for its own sake.
What if the other system has no API?
We use whatever supported extension point exists: scheduled database reads, file exchange or scripting hooks. We assess the options and flag where the only safe path is a vendor change.
How do you prevent duplicate records?
Idempotency keys on every write, so a retry after a timeout is recognised as the same operation rather than creating a second order.
How do we know an integration is healthy?
Monitoring, alerting on failure and queue depth, and a reconciliation job that compares both sides and reports mismatches rather than assuming success.
Services that pair with this
Custom Software Development
Applications shaped around how your business actually works, not around a product roadmap.
Read moreData Engineering & Enterprise Technology
Pipelines, warehouses, dashboards and database work that make reporting consistent and fast.
Read moreCloud, DevOps & Infrastructure
Infrastructure as code, CI/CD pipelines, containerisation and monitoring you can operate yourself.
Read more