Service

API Development and Integration Services

We design, build and document REST APIs and integrations that let your applications, partners and data flow together securely — without fragile scripts and manual exports.

APIs are the backbone of modern software

Almost every system we build depends on APIs: mobile apps talk to a back end, the website sends leads to the CRM, orders flow from e-commerce to the ERP, partners pull stock levels overnight. When those connections are well designed, adding a new channel or partner is straightforward. When they are CSV exports and scheduled scripts nobody understands, every change is risky.

What we deliver

Public and partner APIs

APIs that customers and partners integrate with — often a product in their own right. We focus on consistent resource design, clear versioning, predictable error responses and excellent documentation, because developer experience decides adoption.

Internal APIs

Back ends for web and mobile apps, and service-to-service APIs inside your platform. See our mobile app development and web application development services.

Third-party integrations

Connections to payment providers, accounting packages, shipping carriers, marketplaces, CRM and ERP systems, identity providers and government services.

Integration middleware

For businesses with many systems, a central integration layer — using queues, event-driven messaging and scheduled jobs — keeps each system decoupled and makes failures visible and recoverable.

Design principles we follow

  • Contract-first design with OpenAPI specifications agreed before implementation
  • Versioning and deprecation policy so consumers are never broken without warning
  • Authentication with OAuth 2.0 / OpenID Connect, API keys only where appropriate, and fine-grained scopes
  • Rate limiting, idempotency keys and pagination for robustness under real-world load
  • Retries, dead-letter queues and alerting on every integration, so a failed sync is noticed and replayed rather than silently lost
  • Automated contract tests that run in CI

Technology

We build APIs primarily with ASP.NET Core, which offers excellent performance and first-class OpenAPI support, and host them on Azure API Management or AWS API Gateway where a gateway adds value. Integrations use Azure Service Bus, AWS SQS/SNS or RabbitMQ. Learn more on our REST APIs technology page.

Fixing fragile integrations

A common engagement starts with an audit of existing integrations: what connects to what, how often it fails and what data is at risk. We then replace the most fragile links first, typically seeing a sharp fall in manual reconciliation work. That foundation also makes business automation far easier to build.

    • What you get

      • Production APIs and connectors

        Deployed behind a gateway with monitoring in place.

      • OpenAPI specifications

        Versioned contracts for every API.

      • Developer documentation

        Guides, examples and a sandbox for consumers.

      • Integration runbooks

        Procedures for handling failures, replays and credential rotation.

    • Industries we serve

      • E-commerce

        Custom e-commerce platforms, headless storefronts and back-office integrations for online retailers who have outgrown templates and manual order handling.

      • Logistics

        Fleet tracking, driver apps, dispatch and warehouse software for logistics, courier and distribution companies that need live visibility and proof of delivery.

      • Finance

        Secure software for lenders, brokers, accountancy practices and fintech teams: client portals, workflow automation, reporting and integrations with financial systems.

      • Healthcare

        Patient booking apps, clinic management systems and secure portals for private clinics and healthcare providers, built with privacy and reliability first.

    Benefits

    Why invest in api development & integration

    • Systems that stay in sync

      Reliable integrations remove manual exports and the errors that come with them.

    • Faster partner onboarding

      Documented, versioned APIs let partners integrate without lengthy back-and-forth.

    • Failures you can see

      Monitoring, alerting and replay mean a failed sync is fixed in minutes, not discovered weeks later.

    • Future channels made easy

      A clean API layer lets you add new apps and services without touching core systems.

    Capabilities

    What we build and deliver

    • REST API design

      Resource-oriented APIs with OpenAPI specifications and consistent conventions.

    • Secure authentication

      OAuth 2.0, OpenID Connect, scoped tokens and API key management.

    • Developer portal

      Interactive documentation, sandbox environments and code samples.

    • Event-driven integration

      Webhooks, message queues and event streams for real-time data flow.

    • Resilience built in

      Rate limiting, retries, idempotency and dead-letter handling.

    • Integration monitoring

      Dashboards and alerts for throughput, errors and latency on every connection.

    Process

    How we deliver

    A transparent, milestone-based process with working software at every stage.

    • Integration landscape audit

      Map systems, data flows, volumes and failure points across your organisation.

    • API contract design

      Define resources, schemas, auth and versioning in OpenAPI and review with consumers.

    • Implementation

      Build APIs and connectors with automated unit, integration and contract tests.

    • Security and load testing

      Penetration-style checks, auth review and load tests at expected peak volumes.

    • Release and monitoring

      Publish documentation, onboard consumers and set up alerting and runbooks.

    Technologies

    Technology we use for this service

    • REST APIs

      Well-designed, documented REST APIs that connect web and mobile apps, partners and third-party systems such as payments, ERP, CRM and logistics platforms.

    • ASP.NET Core

      ASP.NET Core is our default framework for secure web applications and REST APIs: fast, cross-platform and well suited to complex business logic and integrations.

    • Microsoft Azure

      We design, build and run applications on Microsoft Azure: App Service, containers, Azure SQL, Functions and Azure OpenAI, with security and cost control built in.

    • Amazon Web Services

      We build and operate applications on Amazon Web Services, using managed containers, databases, serverless functions and storage with sound security and cost practices.

    • PostgreSQL

      PostgreSQL is our open-source database of choice for SaaS platforms and cost-sensitive systems, with strong reliability, JSON support and vector search for AI features.

    • .NET

      We use Microsoft .NET to build fast, secure and maintainable business software: web APIs, ERP and POS back ends, background services and cross-platform apps.

    Related work

    Projects we've delivered

    • Fleet Logistics Tracking App

      A driver app and dispatch dashboard for a regional delivery company, with live vehicle tracking, digital proof of delivery and optimised route sequencing.

    • Smart Education ERP

      A unified education management platform for schools, colleges, universities, and multi-campus institutions, covering admissions, attendance, timetabling, fee management, examinations, academic records, and parent and student portals in one integrated system.

    • Manufacturing ERP Rollout

      A custom ERP for a mid-sized metal fabrication manufacturer, connecting sales orders, production planning, inventory, purchasing and finance in one system.

    Case studies

    Results from similar engagements

    • Retail Chain POS Modernisation

      How a 60-store retail chain replaced ageing on-premise tills with an offline-capable cloud POS, cutting checkout times by 35% and ending overnight price syncs.

    • AI Support Assistant for a B2B SaaS Company

      How a B2B SaaS company deployed a grounded AI support assistant that resolves 42% of conversations on its own and hands the rest to agents with full context.

    What our clients say

    • We used to lose half a day's takings every time a store's broadband went down. Since the new tills went in, outages barely register, and head office can change a price at lunchtime and see it on every shelf-edge promotion by the afternoon.

    • Parents now have one app instead of four, and our office teams have stopped spending Monday mornings chasing absence calls. The migration was the part we worried about most, and the trial runs meant there were no surprises on go-live day.

    • The assistant resolves the repetitive how-do-I questions and hands everything else to us with a proper summary. Our agents spend their time on the tricky tickets now, and customers get answers at 2am without us adding a night shift.

    Solutions

    Related software solutions

    • ERP Software

      Modular ERP software that connects finance, purchasing, inventory, production, sales and HR in one system, configured to your processes and rolled out in phases.

    • AI Business Automation

      AI business automation platform that reads documents, classifies requests and runs multi-step workflows across your systems, with human approval where it matters.

    • AI Customer Support

      AI customer support assistant that answers questions from your own knowledge base, takes actions through your systems and hands off to human agents with full context.

    FAQ

    Frequently asked questions

    • What is the difference between API development and API integration?

      API development means building an API that others call — for your apps or partners. API integration means connecting your systems to existing APIs, such as a payment provider or accounting package. Most projects involve both.

    • How do you secure APIs?

      We use OAuth 2.0 and OpenID Connect with scoped tokens, enforce HTTPS, validate every input, apply rate limits and log access. Sensitive APIs sit behind a gateway with additional policies.

    • Can you integrate with legacy systems that have no API?

      Often, yes — through database-level integration, file exchange, or by building a small API wrapper around the legacy system. We assess the safest option during the audit.

    • Do you document the APIs you build?

      Always. Every API ships with an OpenAPI specification and developer documentation, and public APIs get a developer portal with examples and a sandbox.

    Insights

    Further reading

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