API integration services in the United Kingdom

Check for a ready-made connector first. An official integration between products may cover the common flow you need without a custom build. Look at what it actually transfers and what your staff need to change: a connector that covers the routine case still needs to fit the way you use each system.

Zapier or Make suits a simple, low-volume flow that your staff want to adjust themselves. Custom code suits higher volumes, complex rules or strict error handling. The choice affects how much control you have over the logic and how much work goes into building it. Start with the flow you need to run, including the cases that need attention when it fails.

With a few systems, direct connections can work well. As more systems are added, a central integration service helps avoid a tangle of individual links. If a system has no API, exports or email are often an option, though those routes need their own handling. We learn your business and goals, then agree the scope with you before design and build begin.

The UK government has published e-invoicing requirements for VAT-registered businesses and public bodies, with Peppol as the core interoperability framework. If your invoice integration falls within that scope, we map the invoice fields and accounting connection with that framework in mind. The mapping needs to account for differences in identifiers, formats and tax codes, as well as records that exist in only one system. Agreeing those details before the connection is built gives the people responsible for invoices a clear view of what will move between systems.

Start by deciding which system should be the source of truth for each piece of data, such as stock, customer details or payment status.

• List your systems, their plans or editions, and whether API access is included. Some vendors reserve it for higher tiers.
• Arrange admin access or API credentials under a business-owned service account, plus sandbox accounts where available.
• Name the owner of each system and gather vendor support contacts for questions about permissions and limits.
• Decide who receives a failed-sync alert and how quickly someone needs to act.
• Identify who owns keys or OAuth tokens, how they are stored securely and who renews them before expiry.

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  Conflicting sources

  A two-way sync can overwrite good data with stale data. Agree which copy is authoritative before allowing updates in both directions.

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  Duplicate events

  Webhooks can arrive twice or out of order. Log processed event IDs and avoid depending on delivery order.

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  Silent failures

  Missing orders or invoices can go unnoticed when a sync fails without an alert. Make sure a failure reaches someone who can act.

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  Testing only the happy path

  Include blanks, odd characters, duplicates and cancelled orders when checking mappings against real-world data.