API Development & Integrations
Custom APIs and reliable integrations that connect your website, apps, payment providers and business tools.
Make your systems talk to each other
Most businesses run on a mix of tools: a website, a CRM, an accounting package, a payment provider, email marketing, maybe a mobile app. When they don't share data, people fill the gaps by copying and pasting, and errors creep in.
Maetheon Ltd builds custom APIs and integrations for businesses in the UK, the US, Canada and Australia. We design clean, documented REST APIs for your own products, and connect the third-party services you already rely on, with logging and retries so data keeps flowing when something goes wrong.
Integration work is central to our own products. Our 17 picker tools depend on social media platform APIs and payment webhooks every day, so we understand rate limits, authentication, changing platform rules and graceful failure. You can read more in our case studies.
Integration work we deliver
Custom REST APIs
Well-structured, versioned APIs with authentication, rate limiting and documentation.
Payment integrations
Stripe and PayPal checkouts, subscriptions, webhooks and reconciliation.
CRM & sales tools
Syncing leads, contacts and deals between your website, CRM and email tools.
Accounting & operations
Invoices, orders and stock moving between your shop, accounting and fulfilment tools.
Social platform APIs
Integrations with major social platforms' official APIs, built within their terms of use.
Automation & webhooks
Event-driven workflows, scheduled syncs and alerts that remove manual work.
Signs you need an integration
A good fit if you…
- Re-type the same data into several systems
- Need a mobile app to use your existing data
- Want partners or customers to access your data securely
- Are replacing a fragile Zapier-style workflow
- Need payments connected to your own software
What makes an integration reliable
Plan for failure
Third-party services go down, time out and change. Reliable integrations use queues, retries with back-off and clear error logs, so a temporary problem doesn't lose data or create duplicates.
Respect rate limits and terms
Most platforms limit how often you can call their APIs and set rules on how data may be used. We design around these limits from the start and build only on official, permitted access. That's how our own social media tools operate.
Keep secrets secret
API keys and tokens belong in secure configuration, not in code or spreadsheets. We use least-privilege access, rotate credentials where possible and document who owns each connection.
Our process
Integration audit
We map your systems, data flows and the problems to solve.
Design
Data mapping, API design and error-handling plan.
Build & test
Development against sandbox environments with automated tests.
Go live
Careful rollout with monitoring and alerts.
Maintain
Updates when third-party APIs change.
Pricing & timelines
| Option | What it covers | Starting price |
|---|---|---|
| Single integration | One system connected to another | From £3,500 |
| Custom API | Documented API for your product or partners | Quoted on scope |
| Integration maintenance | Monitoring and updates for API changes | From £1,200 / month |
Typical timeline: 3–8 weeks depending on the systems involved. Prices exclude any applicable taxes; every project gets a fixed written quote. See the full pricing guide.
Why work with us
A UK contract
You work with a company registered in England & Wales, with written scopes, clear terms and invoices in GBP.
Fixed, transparent pricing
Written quotes and milestone billing. Any change in scope is quoted before we do the work.
You own the results
Code, designs, footage and accounts belong to you on final payment, with full handover.
Experience from our own products
We run 17 live products, so launches, growth, support and search visibility are everyday work for us.
Frequently asked questions
What's the difference between an API and an integration?
Can you integrate with software that doesn't have an API?
What happens when a third-party API changes?
Is our data secure?
Do you document the APIs you build?
Related services
Areas we serve
Need your systems connected?
Tell us what you want to build or grow. We reply within one business day with clear next steps and a written quote.