Third-Party API Integration Services

Payment platforms (Stripe, Stripe Connect, PayPal, GoCardless), CRMs (HubSpot, Salesforce, Pipedrive), marketing automation (Mailchimp, ActiveCampaign, Klaviyo), eCommerce (Shopify, WooCommerce, Magento), shipping and fulfilment (Royal Mail, DPD, ShipStation), analytics (GA4, Mixpanel, Segment), communication (Twilio, SendGrid, Slack), and most bespoke partner APIs your business runs. If the third party publishes an API and authentication model, we can integrate with it.

An idempotent handler produces the same outcome whether it runs once or ten times for the same event. This matters because webhooks are commonly delivered more than once — the third party retries when it doesn't get an acknowledgement quickly enough, network glitches cause duplicates, and load balancers occasionally double-deliver. Without idempotency, every duplicate webhook can double-charge a customer, double-create a contact, or double-fulfil an order. We build idempotency in by default — usually keyed on the third party's event ID — so duplicate delivery is harmless.

Every webhook receiver verifies the signature using the third party's signing secret before doing any work. Spoofed webhooks fail validation and are rejected — they cannot trigger real actions. The signing secret itself lives in a managed secrets vault rather than an environment file, and rotation procedures are documented in your runbook.

Third parties version their APIs and publish deprecation notices, typically with multi-month lead times. On maintenance retainers, we monitor those notices and migrate before the deprecated version is removed. For one-off integrations, we document the API version in use so your team knows what to watch and can either handle the migration themselves or bring us back in when it is required.

Sometimes. If the platform has any kind of programmatic interface — undocumented APIs, RSS feeds, scraped HTML, or file-based exports — we can usually build a connector around it, with the trade-off being more fragile reliability than a documented API would provide. Where no interface exists at all, we work with you to identify the best alternative path (CSV exports, manual sync, or escalating with the vendor).

Three layers. First, every integration is monitored — webhook delivery rate, queue depth, retry rate, authentication failure rate — with alerts that route to engineers when something drifts. Second, dead-letter queues capture events that exhaust retries so they don't disappear silently. Third, reconciliation jobs run on a schedule and compare your local state against the third party's source of truth, flagging any divergence before it shows up in customer complaints or accounting reports.

Yes. For workflows that span multiple third parties — lead to CRM to invoicing to marketing automation, or order to payment to fulfilment to customer notification — we typically combine third-party integration with our API integration and automation service. The workflow is implemented as a coordinated set of integrations rather than a brittle chain of point-to-point connections.

For payment integrations we follow Stripe and PayPal's PCI guidance — typically using their hosted checkout or Elements to keep card data out of your systems entirely, so PCI scope stays minimal. For GDPR-relevant integrations, we configure proper data-residency, retention policies, and audit logging. We can produce data-processing documentation on request for compliance reviews.

Available on retainer for ongoing monitoring, version migration when third parties deprecate API versions, incident response when something upstream breaks, and feature additions as your operations evolve. Pairs naturally with our managed UK hosting and API testing & monitoring services for a fully-supported production integration.