These tend to appear as soon as a product has more than one client application or more than a couple of partners.
The web app's back end was never meant to be called from phones, and it shows.
Customers or resellers ask for an API, and you don't have one you'd want to publish.
Orders, contacts or inventory are exported and re-entered between tools every day.
A provider you depend on announced a new version, and your integration needs rework before a deadline.
No contract tests, no versioning and no clear owner for the API surface.
New models, search or analytics need clean, well-structured data from your system.
REST APIs designed around your domain, with consistent naming, errors and pagination.
The services, data models and background jobs behind your API, in Node.js or Python.
Payments, CRM, ERP, shipping, analytics, identity and AI services connected to your product.
APIs that external developers can use, with keys, rate limits, versioning and onboarding docs.
Event-driven integrations with retries, queues and idempotent handlers so nothing gets lost.
Reliable data exchange between your internal tools, warehouses and legacy systems.
Authentication, authorization, input validation and rate limiting checked against real attack patterns.
OpenAPI specs, examples and client libraries that make your API easy to adopt.
Whether it serves your own front end or many partners, the same basics decide whether an API is a pleasure or a pain to use.
Spec agreed before implementation
Consistent resources, errors and pagination
Versioning strategy from the first release
Docs generated from the spec, so they stay current
Token-based authentication
Permissions checked on every request
Rate limits and quotas per client
Secrets kept out of code and logs
Retries with backoff for external calls
Queues for slow or bursty work
Idempotent webhook handling
Contract tests against third-party sandboxes
Structured logs for every request
Alerts on errors and slow endpoints
Usage metrics per client
Clear runbooks for common failures
You need a public or partner API, or your internal API has become hard for your own teams to use.
Your web app needs a mobile app, a partner channel or an AI feature, all on the same back end.
Your CRM, ERP, store and accounting tools don't talk to each other, and people fill the gaps by hand.
You build the front end and need a reliable partner for the API and integration work behind it.
Contract, architecture and first endpoints.
Payments, CRM, ERP or AI providers.
Keys, limits, docs and onboarding.
Consistency, versioning and documentation.
Find the cause and make them reliable.
Back end ready for mobile or web clients.
We list who calls the API, what they need and which external systems are involved, including their limits and quirks.
Resources, payloads, errors and auth are written as a spec you can review before any code is written.
Endpoints and integrations built in sprints, with automated and contract tests against sandboxes and real data samples.
Access rules, rate limits and a security review, plus documentation and examples for every consumer.
Versioned release, logging, alerts and usage metrics, then ongoing support as consumers and providers change.
One API or a defined set of integrations
Fixed price after scoping.
For a clear piece of work: a new API, a payment or CRM integration, or a partner endpoint set.
Scope and contract agreed up front
Built and tested against provider sandboxes
Documentation for your team
Monitoring set up before launch
Hand-over or ongoing support
Backend engineers and QA on your platform
Monthly, per engineer or team.
For products where APIs and integrations are a constant stream of work, not a single project.
Engineers matched to your stack
Ownership of the API surface
Versioning and deprecation managed
Contract tests in your pipeline
Scale up when new integrations arrive
An AI-powered fashion commerce platform that helps retailers deliver personalized shopping experiences through virtual styling, AI recommendations, image search, and intelligent product discovery.
An AI-powered payroll validation platform that extracts data from salary slips, verifies payroll calculations, and automates reporting and approval workflows for HR and finance teams
Most of the products we build depend on external services and several client apps. Getting the API layer right is everyday work for our back-end engineers.
APIs serving web apps, iOS and Android apps from one back end.
Node.js, NestJS, Express, Python, FastAPI and Django.
RabbitMQ, AWS Lambda, Docker and Kubernetes.
Work can start in about two weeks.
85% of our customers come back with new work.
You review the API design before it's built.
Documentation ships with the code, not months later.
Retries, queues and alerts for every external dependency.
Keys, repositories and infrastructure stay with you.
Engineers in Europe overlap with part of the US working day.
No sales pitch
Tell us what needs to connect
Describe your product, the systems involved and who will use the API. We'll suggest an approach and come back with a rough estimate.
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