API Integration Services: Connect the Tools Your Business Runs On
Most companies already own the software they need. What they do not have is the connections between it, so someone re-types the same order into three systems every morning. Integration work removes that person from the loop.
Discuss your projectThe four shapes integration work takes
Knowing which one you need changes the cost more than the choice of vendor does.
One-way sync
Records flow from a source of truth into a second system. Simple, predictable, and the right answer more often than people assume. Orders into accounting is the classic case.
Two-way sync
Both systems can change the same record, so something has to decide what happens when both change it before the sync runs. That conflict rule is the whole job; the API calls are the easy part.
Event-driven
A webhook fires and work happens immediately. Fast and efficient, but webhooks get delivered twice, out of order, or not at all, so the receiving end has to be built to tolerate all three.
Custom API
When you are the system others integrate with — exposing your own documented API for clients, partners, or your mobile app, with authentication, versioning, and rate limits.
Integrations we build most often
Stripe, for subscriptions, one-off payments, and the webhook handling that keeps your records in step with what actually got charged. Most Stripe problems we are called in to fix are not payment failures; they are webhooks that were processed once and never made idempotent, so a retry double-counted.
HubSpot, for pushing qualified leads in from forms, chat, or voice agents, and keeping deal stages aligned with what your own systems believe. HubSpot's rate limits are low enough that bulk operations need queueing rather than a loop.
QuickBooks and Xero, for invoices, payments, and the chart-of-accounts mapping that has to be agreed with your bookkeeper before a line of code is written. Accounting integrations fail on taxonomy, not on technology.
Shopify, for orders, inventory, and fulfilment, including multi-location stock where two channels can sell the last unit within the same second.
Beyond those: Salesforce, Zoho, GoHighLevel, Slack, Google Workspace, Microsoft 365, Calendly, Twilio, and a long tail of industry systems whose documentation is a PDF from 2017. We quote that long tail honestly, because it takes longer.
Reliability, which is most of the work
An integration that works on a good day is not finished. These are the failure cases we build for as standard.
- Retries with backoff, so a vendor's five-minute outage does not drop your data on the floor.
- Idempotency, so the same webhook delivered twice does not create two invoices. Vendors retry more often than their documentation suggests.
- A dead-letter queue, so records that fail repeatedly are held for inspection rather than discarded silently.
- Rate-limit awareness, including the vendors that return a 200 while quietly throttling you.
- Alerting on the thing that actually matters — a sync that has stopped producing records — rather than on raw error counts, which are noisy and get ignored.
- A reconciliation job that compares both systems on a schedule and reports drift, because every long-running sync eventually drifts.
Off-the-shelf connector or custom integration
Zapier, Make, and native connectors are genuinely the right answer for a lot of work. Here is where they stop being it.
| Off-the-shelf connector | Custom integration | |
|---|---|---|
| Setup time | Hours | Days to weeks |
| Monthly cost | Per-task pricing, rises with volume | Hosting only, flat |
| Conditional logic | Limited, awkward past a few branches | Unrestricted |
| Field mapping | Whatever the connector exposes | Any field either system has |
| Error handling | Email on failure, manual replay | Retries, dead-letter queue, alerting |
| Volume ceiling | Gets expensive fast | Scales on your infrastructure |
| Who can change it | Anyone on your team | A developer |
Our usual advice: start with a connector. Move to custom when the per-task bill becomes noticeable, when the logic no longer fits, or when a silent failure would cost you more than the build.
Common questions
Tell us what you need
Describe the problem and we will come back with scope, timeline, and a rate. No obligation to proceed.
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