API Development
& Integration

REST APIs, GraphQL, OAuth2, webhooks, and API gateways - designed for reliability, documented for developers, and secured for production from day one.

REST & GraphQL OAuth2 & JWT Auth API Gateway & Management OpenAPI Documentation
60+ APIs built and integrated
99.9% Uptime SLA on managed API endpoints
15+ Third-party platforms integrated
Overview

APIs that connect your systems reliably - and don't break when traffic spikes

We design and build APIs that are production-ready from the start - with proper versioning, error handling, rate limiting, and authentication baked in, not bolted on later.

DynamicUnit's API practice covers greenfield REST and GraphQL development, integration with third-party platforms (ERP, CRM, payments, logistics), and API gateway setup via Azure APIM or AWS API Gateway. Every API we ship includes OpenAPI/Swagger documentation and a test suite — so your developers can consume and maintain it without guesswork.

We build APIs in .NET (ASP.NET Core) and Python (FastAPI / Django REST Framework) depending on your ecosystem. For Dynamics 365 integrations, we use OData and custom services. Our website development team consumes these APIs to power front-end features, and our Azure practice hosts them on App Services, Container Apps, or Functions.

What's included

  • RESTful API design & development
  • GraphQL schema design & resolvers
  • OAuth2, JWT & API key authentication
  • Webhook implementation & delivery guarantees
  • API gateway setup (Azure APIM / AWS)
  • OpenAPI / Swagger documentation
  • Monitoring, logging & alerting
Industries We Serve

API solutions built for your industry

E-Commerce & Retail

Product catalogue APIs, order management integrations, payment gateway connectors, and inventory sync between e-commerce platforms and ERP systems.

Enterprise & ERP

Custom APIs connecting Business Central, D365 F&O, and CRM to portals, mobile apps, and third-party platforms.

Logistics & Supply Chain

Shipment tracking APIs, warehouse management integrations, carrier rate-shopping connectors, and real-time status webhooks for order fulfilment.

Financial Services

Secure transaction APIs, open banking integrations, KYC verification connectors, and regulatory reporting endpoints with audit logging and encryption.

Our Capabilities

End-to-end API design, delivery, and management

From initial contract design to live monitoring - here's what our API practice delivers.

REST API Development

Resource-oriented APIs with consistent response structures, proper HTTP semantics, versioning strategy, and full error handling.

GraphQL APIs

Schema-first GraphQL design with efficient resolvers, DataLoader batching, and subscription support for real-time use cases.

Authentication & Security

OAuth2 flows, JWT validation, API key management, rate limiting, and CORS policy - all configured before any data leaves the wire.

Webhooks & Event Delivery

Outbound webhooks with retry logic, signature verification, delivery logs, and dead-letter handling for guaranteed message delivery.

API Gateway & Management

Azure APIM or AWS API Gateway setup - routing, throttling, caching, developer portal, and analytics in one managed layer.

Third-Party Integrations

Connect to Dynamics 365, Salesforce, Stripe, logistics platforms, and industry-specific systems with properly error-handled adapters.

API Documentation

OpenAPI/Swagger specs, Postman collections, code examples, and a developer-facing portal so consumers can integrate quickly.

Monitoring & Observability

Request tracing, latency dashboards, error rate alerting, and structured logging so problems are caught before customers notice.

Why DynamicUnit

What sets our API practice apart

Many developers can write an endpoint. Fewer think about contract stability, consumer experience, and operational observability from the start. We do.

Contract-First Design

We define the API contract in OpenAPI before writing code - so consumers and producers are aligned before implementation begins.

Security Is Not Optional

Every API we ship has authentication, input validation, and rate limiting configured by default - not added in a security review three months later.

Documentation That's Actually Useful

We write docs for the developers consuming the API - with real request/response examples, error codes explained, and edge cases covered.

Versioning & Backward Compatibility

Breaking changes are managed through versioning strategies - consumers are never surprised by a midnight deprecation with no migration path.

Built for Scale

Connection pooling, caching headers, async processing for heavy operations - designed to handle production load from day one.

Tested Before It Ships

Unit tests, integration tests, and contract tests are part of every delivery - not an afterthought committed the night before go-live.

How We Work

From contract design to production API in 4 phases

1
Requirements & Contract Design

We map the consumers, data flows, and integration points. The API contract is defined in OpenAPI before development begins - so all stakeholders are aligned on endpoints, schemas, and authentication.

2
Development & Testing

We build the API in .NET or Python with unit tests, integration tests, and contract tests. Documentation and Postman collections are generated alongside the code.

3
Gateway & Security Setup

API gateway configuration (Azure APIM or AWS), OAuth2 authentication, rate limiting, CORS policies, and monitoring dashboards - all configured before the first consumer connects.

4
Go-Live & Managed Support

Production deployment, consumer onboarding documentation, and ongoing support. We monitor uptime, error rates, and latency - and handle versioning and deprecation as your API evolves.

FAQ

Common questions about API development

REST is the right choice for most public-facing or integration APIs - it's predictable, widely understood, and simple to cache. GraphQL makes more sense when multiple clients (web, mobile, third-party) need flexible querying of the same data without over-fetching. We'll recommend the right approach for your use case after understanding your consumers and data model.

Yes. We have hands-on experience integrating with Dynamics 365 Finance & Operations, Business Central, Salesforce, and various logistics and industry platforms. Integrations are built with proper error handling, retry logic, and logging - not just a point-to-point call that breaks silently when the upstream system is slow.

Authentication (OAuth2 client credentials, authorization code, or API keys depending on the use case), TLS in transit, input validation at every endpoint, rate limiting, and CORS policy are all standard. For higher-security environments we also implement IP allowlisting, request signing, and audit logging.

Yes - full OpenAPI 3.x specification, a Postman collection, inline code examples, and a description of all error codes and their resolution steps. If you need a developer portal we can configure one through Azure APIM or a hosted Swagger UI deployment.

We build adapters and anti-corruption layers that isolate your system from upstream changes. For critical integrations, we implement circuit breakers and fallback behaviour so a third-party outage degrades gracefully rather than taking your whole application down. Monitoring alerts are set up to notify your team the moment error rates spike.

A focused API with 5-15 endpoints, authentication, and documentation typically takes 3-6 weeks. Complex integration projects involving multiple third-party systems, webhook infrastructure, and API gateway setup run 6-12 weeks. We provide a detailed timeline after the contract design phase.

Costs depend on the number of endpoints, integration complexity, and infrastructure requirements. A straightforward REST API project typically falls in the mid four to low five-figure range. We provide a fixed-scope quote after the contract design phase so you know exactly what you're paying for.

Need an API built properly, not just quickly?

Share your integration requirements - we'll review the architecture and give you a clear plan with realistic timelines.

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