Salesforce Integration Developers UK

What we connect Salesforce to

Salesforce is often the place sales and service work happens, but the money, stock and delivery live elsewhere. Typical integrations we build:

• Accounting. Closed-won opportunities become invoices in Xero, Sage or QuickBooks, with payment status and credit limits flowing back to the account.
• ERP and stock. Products, price books and availability sync from your ERP so quotes use live figures. See ERP development.
• Ecommerce. Online orders and customers land on the right account, so sales see the whole relationship.
• In-house systems. Job management, booking or production systems that need to know when a deal is won, and that update Salesforce when work is delivered.

Choosing the right Salesforce API

Salesforce offers several APIs, and choosing well keeps the integration fast and inside its limits:

• REST API for reading and writing individual records, with the Composite API grouping related changes into one request.
• Bulk API 2.0 for large loads such as a full product catalogue or a historical migration, processed asynchronously in jobs.
• Change Data Capture to receive an event whenever selected records are created or changed, instead of polling. Events are delivered through the Pub/Sub API or CometD.
• Platform Events for custom business events, such as "order dispatched", that both sides can publish and subscribe to.

Updates use external ID fields and upserts, so a retried message updates the same record rather than creating a duplicate. That idempotency is what makes a sync safe to rerun after a failure.

Authentication and the move to External Client Apps

Integrations used to authenticate through connected apps. From the Spring '26 release, Salesforce disabled the creation of new connected apps by default and recommends External Client Apps for new integrations. Existing connected apps still work, but Salesforce is moving everyone across, and older flows such as username and password sign-in are being retired. We build new integrations on External Client Apps using the OAuth 2.0 JWT bearer or client credentials flow, with no passwords stored anywhere, and we migrate existing integrations when you are ready.

The integration runs as a dedicated integration user, not a member of staff. Salesforce gives Enterprise, Unlimited and Performance orgs five free Salesforce Integration user licences, which are API only and cannot log in to the interface. A permission set grants exactly the objects and fields the integration needs, nothing more.

Editions and API limits

Check your edition first. Enterprise and Unlimited editions include API access. Salesforce's add-ons list sells a Web Services API add-on for Starter and Pro Suite, and the legacy Professional Edition does not include API access by default. We confirm this before quoting, because it changes what is possible.

Salesforce allocates API requests over a rolling 24-hour period, based on edition and the number of licences, and caps long-running concurrent requests. We keep within it by using Change Data Capture instead of polling, Composite requests to cut round trips, and Bulk API 2.0 for anything large. A dashboard shows calls used, so you see trouble long before Salesforce starts refusing requests.

Reliability and testing

Every integration logs each message with its outcome. Failures go to a queue for automatic retry with backoff, and anything that still fails raises an alert with enough detail to fix it, such as a missing required field or a validation rule that blocked the update. Nothing fails silently.

We build and test in a Salesforce sandbox using realistic data, including the awkward cases: merged accounts, deleted records, validation rules, and two people editing the same record at once. Only then do we deploy to production, usually with a short period of running alongside your current process so you can compare results.

Salesforce releases three updates a year, in spring, summer and winter, and each can change behaviour, retire old API versions or switch on release updates in your org. We pin the integration to a specific API version, read the release notes for anything that affects it, and test in a preview sandbox before each release reaches production. Handover includes a runbook covering how to rotate certificates, add a field to the sync and replay failed messages.

Getting started

Tell us which systems need to talk to Salesforce and what currently gets retyped. We will review your edition, objects and existing integrations, then give a fixed-price quote for a defined scope. See also CRM integration and systems integration, or get in touch.

What we deliver

• An integration design: objects, fields, direction, timing and ownership
• Two-way sync using REST, Composite and Bulk API 2.0
• Event-driven updates with Change Data Capture or Platform Events
• Secure authentication through an External Client App and integration user
• Error queues, retries, alerts and an audit log
• Migration of existing connected-app integrations
• Documentation and tests run against a sandbox

How it works and what it costs

Every project gets a fixed-price quote after a free initial chat and a short scoping stage. You own the code and the data.

1. Free chat

   Tell us the problem in plain English: what you do now, what goes wrong and what "better" looks like. No charge, no obligation.

2. Scoping

   We map the processes, systems and data involved, agree what is in and out, and write it down so there are no surprises.

3. Fixed-price quote

   You get a fixed price for the agreed scope, or a phased plan for bigger builds, so you can start small and prove it works.

4. Build and test

   We build in short stages you can see and try, test against real data, then go live carefully with a rollback plan.

5. Hand over and look after

   You own the code and the data. We can host it, support it and keep improving it, or hand it to your own team.

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