APIs and integrations

API development and integration services that keep systems in sync

We connect CRMs, ERPs, payment gateways, learning platforms and online stores, and build the APIs your own apps depend on. Every sync is designed for timeouts, duplicates and retries.

  • 100+ eCommerce projects
  • Documented, versioned endpoints
  • Failures logged and retried
Get a free quote See our work
What is included
  • REST API development
  • Webhooks in and out
  • Business system connectors
  • Middleware and queues
  • Security and access
  • Monitoring and documentation
Get a free quote Reply within one business day. NDA on request.
The problem

When systems stop agreeing

Integration work starts with a sentence like "when an order is paid, the customer should appear in the CRM and get access to the course". It sounds like one step. In practice it is three systems, two vendors and a list of awkward questions. What if the CRM is down for ten minutes? What if the payment gateway sends the same notification twice? Who finds out when a record is rejected?

We build the connection and answer those questions in the design. Sometimes that means a small plugin inside WordPress or Moodle. Sometimes it means a standalone API or a middleware service that sits between systems and keeps a record of every message. Payments are where this matters most, and with 100+ eCommerce projects delivered we have learned to treat the unhappy path as the main part of the job.

  • Staff are the integration

    Someone retypes orders into the accounting package and copies enrollments into a spreadsheet for HR. It is slow, it is error-prone, and it stops whenever that person is away.

  • A sync that fails silently

    The connector worked for months, then an API key expired or a field was renamed. Nobody noticed until a customer complained, and now a week of records has to be repaired by hand.

  • Duplicates and half-finished records

    A timeout caused a retry, the retry created a second invoice, and the stock count is off by one. Each of the two systems believes it holds the correct version.

  • No-code automation at its limit

    A chain of Zapier or Make steps handled the first few cases. Now it has branches nobody can follow and no safe way to test a change before it goes live.

What we do

Integration work we take on

We write APIs for others to consume and we consume other people's, usually in the same project. In both directions the work is the same mix of mapping, error handling and proof that the data arrived.

REST API development

Resource-based endpoints with consistent naming, pagination, filtering, validation errors a client can act on, and a version in the URL or header so old consumers keep working.

Webhooks in and out

Receivers that verify signatures, acknowledge quickly and process in a queue, plus outgoing webhooks from your system with retries and a delivery log your customers can read.

Business system connectors

Two-way sync with CRM, ERP, accounting, payment, shipping and learning platforms, with a field map agreed in advance and a rule for which side wins a conflict.

Middleware and queues

A small service between systems that reshapes, queues and retries messages, so a slow or offline vendor does not block a checkout or lose an update.

Security and access

API keys, OAuth 2.0 or signed tokens depending on who is calling, scoped permissions, rate limits, input validation and secrets kept out of the codebase.

Monitoring and documentation

Request logs, failure alerts by email or chat, a dashboard of pending and failed jobs, and OpenAPI documentation with examples a third-party developer can follow.

Typical projects

Connections we build most often

01

Store to accounting and fulfillment

Paid orders, refunds, customers and stock levels passed between an online store, the accounting package and the warehouse or carrier, with each order sent once and traceable.

02

LMS to HR or CRM

Enrollments created from the HR system or a deal stage, and completions, grades and certificates written back, so training records live where managers already look.

03

A public API for your product

Documented endpoints, keys and rate limits that let your customers and partners build on your platform without direct database access or one-off favors from your developers.

04

One back end for web and mobile

A single API serving the browser application and the Flutter or native app, with token authentication, push notification hooks and versioning for older app releases.

In depth

Designing an integration that fails safely

Start with a field map and an owner

Before any code we draw a table: each field in system A, where it lands in system B, what format it takes on the way, and which system is the source of truth. Customer email might belong to the CRM while billing address belongs to the store. Writing this down settles most arguments early, and it exposes the fields with no home, which is where integrations usually stall. The same table becomes the acceptance test.

Polling, webhooks or both

Webhooks are fast and cheap, since the other system tells you when something changed. They also get lost. Servers restart, deliveries time out and some vendors stop retrying after a few attempts. For anything that matters we pair webhooks with a scheduled reconciliation job that asks "what changed since my last successful run" and repairs the gaps. Where a vendor offers only polling, we store a cursor or timestamp and respect its rate limits instead of hammering it.

Idempotency, so a retry is harmless

Networks fail halfway. The request reached the other side, the response did not come back, and now you do not know whether the invoice exists. The fix is to make every write safe to repeat. We give each operation a unique key, store the keys we have processed, and look up before creating. Payment providers such as Stripe support idempotency keys for exactly this reason. Retries then run on a queue with growing delays, and after a set number of failures the message moves to a failed list where a person can inspect and replay it.

Where the code should live

If one system is clearly the hub, the integration belongs inside it: a plugin for WordPress API integrations, a local plugin and web services for Moodle integration. When three or more systems are involved, or none of them is yours to extend, a separate middleware application is cleaner. We usually write it as a Laravel API, because queues, scheduling, validation and logging are already there.

Security and life after launch

Credentials sit in environment configuration, never in the repository. Incoming calls are authenticated, validated and rate limited, and we follow OWASP API security practices when you ask us to build and test to them. After launch the integration reports on itself: a log of every exchange, alerts on repeated failures and a simple screen showing what is queued, sent and stuck. Vendors change their APIs, so this is the part that pays for itself.

Process

Steps from mapping to monitoring

  1. 1

    Audit the systems

    We read the API documentation for each system, check authentication, rate limits and sandbox access, and confirm what your current vendor plans allow.

  2. 2

    Map fields and events

    A shared document lists every field, trigger and direction of travel, plus the conflict rule. You sign it off before development.

  3. 3

    Build against sandboxes

    Endpoints, receivers and jobs are developed with test accounts and recorded responses, including the error cases vendors rarely demonstrate.

  4. 4

    Rehearse with real data

    A copy of production data runs through the sync. We compare record counts and spot-check values on both sides before switching it on.

  5. 5

    Go live and monitor

    The integration is enabled for a small slice first where possible, then fully, with alerts and a failed-message screen in place from the first day.

Deliverables

What you receive with the integration

  • A signed-off field map and event list
  • API documentation in OpenAPI format with examples
  • Retry, deduplication and reconciliation built in
  • A log and alerting for every failed exchange
  • Source code and credentials under your control
FAQ

API and integration questions answered

Should we build a custom integration or use Zapier?
Use a no-code tool when the flow is simple, low volume and not business critical. Build a custom integration when you need two-way sync, guaranteed delivery, complex mapping or an audit trail. We often start by replacing only the one automation that keeps failing and leave the rest alone.
Which systems can you connect?
Any system with a documented API, a webhook, a database we may read or even a scheduled file export. That covers most CRM, ERP, accounting, payment, shipping, email and learning platforms. Where a vendor has no API at all, we will tell you before quoting.
What happens when one of the systems is down?
Messages wait in a queue and are retried with increasing delays, so nothing is lost during a short outage. After repeated failures the item moves to a failed list, an alert goes to your team, and it can be replayed once the other side is back.
How do you prevent duplicate orders or invoices?
Every write carries a unique key and we check for it before creating a record. A retried request therefore returns the existing record instead of making a second one. A scheduled reconciliation compares both sides and flags anything that still differs.
Will you document the API for our partners?
Yes. You get an OpenAPI specification, a readable reference with request and response examples, and a Postman collection. Authentication, error codes, rate limits and the versioning policy are written down so an outside developer does not need to ask us.
What affects the cost of an integration?
The main drivers are the number of systems, whether data flows one way or both, the quality of each vendor API and sandbox, and how much existing data must be matched first. Two clean APIs with one-way sync is a small job. Legacy systems with file exports take longer.
Can you build the API for our mobile app?
Yes. We design one API for web and mobile clients, with token authentication and versioning so older app releases keep working. The app-side work is described under mobile app API integration.
Related

Laravel API Development

PHP API Development

WordPress API & Integrations

Moodle Integration

Mobile App API Integration
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Which systems need to talk to each other?

Name the systems, the data that should move and how often. We reply within one business day, check the APIs involved and follow up with a mapped plan and a free quote.

  • Free consultation and quote
  • NDA on request
  • You own the source code
  • Reply within one business day
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