API and systems integration — make the tools you already pay for talk to each other

Most businesses do not have a software problem. They have a translation problem. The website captures a lead someone retypes into the CRM. The CRM closes a deal someone retypes into the accounting package. The order that shipped this morning gets marked shipped in three places, on three days. Every one of those tools works. None of them talk.

The second version of this problem is worse, because it looks solved. A sync existed, it ran fine for months, then a rate limit or a renamed field quietly stopped it. Nobody noticed until the month-end numbers were wrong. Integration is not hard because connecting two APIs is hard. It is hard because staying connected is.

What integration means in our hands

We design for the failure, not the happy path. Third-party APIs go down, throttle you, rename a field, or accept a request and lose it. Every integration we ship carries idempotency keys so a retry cannot double-charge or duplicate an order, backoff that respects published rate limits, a queue for repeated failures, and an alert to a human when something needs attention. Silent failure is the one unacceptable outcome.

Reconciliation, not just sync. Sync moves records. Reconciliation proves both sides agree. We build a scheduled check that compares the two systems on the fields that matter and reports the drift, so a discrepancy surfaces the next morning, not at year end.

APIs documented for the developer who did not build them. When we build your API you get versioned endpoints, an OpenAPI specification, authentication that is not a shared password, sandbox credentials and a changelog, so your partner or your next developer can integrate without booking a call with us first.

What a typical engagement includes

• An integration map: every system, the data it owns, the direction it flows, and which side wins a conflict
• Connections into the tools you already pay for: CRM, accounting, payments, shipping, booking, ERP, marketing and support platforms
• REST API design and build, with versioning, an OpenAPI spec, and credentials issued per consumer
• Webhook endpoints and event pipelines with signature verification, replay protection and a dead-letter queue
• Field mapping and transformation, including the awkward parts: currencies, tax codes, time zones, partial records
• Backfill of historical data alongside ongoing sync, with a reconciliation report
• Rate-limit handling, caching, and graceful degradation while a vendor is down
• Monitoring, logging and alerting on every integration point, in an admin screen you can read
• Written runbooks and handover, so your team knows what to do on a Friday evening

The stack and the approach

TypeScript end to end, in the same Next.js 16 codebase as the product where that makes sense. Postgres holds the sync state, the event log and the reconciliation history, so there is no integration SaaS to rent forever and no black box sitting between your systems. Queues and scheduled jobs handle retries and backfills; credentials live in environment configuration, never in the repository.

Where a legacy system offers nothing but a database, an SFTP drop or a nightly CSV, we bridge it: an adapter presenting a clean, modern interface to everything downstream while the old system keeps running untouched. That buys years of breathing room, and it is often the honest alternative to a rebuild nobody has budget for.

What this looks like in practice

Wiring the tools a business already pays for. Website and phone leads land in the CRM automatically; a closed deal creates the invoice in the accounting package; the payment reconciles against it; the shipment writes tracking back to the customer record. Staff who used to retype data spend that hour on customers instead. Frequently paired with a CRM build or an ecommerce store.

Building the API other systems consume. A business with a mobile app, a partner network or a franchise group needs one documented, authenticated, rate-limited API instead of five bespoke exports. We design the contract, build it, document it, and wrap it in monitoring so you can see who calls what. Usually part of a wider custom software or webapp build.

Pricing

Integration work is scoped per project. Two modern APIs and a nightly sync sit at one end; a legacy ERP, a payment provider and eleven years of history to reconcile sit at the other. We scope after a short call, then quote a fixed price against a written specification. Ongoing monitoring can ride on a Care Plan. Contact us for a quote.

Ready to stop retyping?

Send the list of tools you run and the point where the copying starts. We respond within four business hours, and if the fix is a setting in software you already own, that is what you will hear.

Start an integration project or book a 30-min call