Custom API Development ConsultantsDevelopment Consultants
We build APIs that move data fast and stay reliable. Get a fixed-price quote in week 2.
IRPR specializes in custom API development for businesses that need fast, secure data exchange. We handle everything from REST and GraphQL endpoints to event-driven architectures with Kafka and gRPC.
Our senior engineers ship production-ready APIs in 8-12 weeks with fixed pricing from $80K to $250K. All code passes PCI-DSS and HIPAA compliance checks before delivery.
We work with SaaS founders needing to expose platform APIs, healthcare startups building FHIR-compliant backends, fintech companies requiring PCI-grade payment gateways, and ecommerce brands scaling their inventory integrations.
Types of software we ship.
REST API Development
Build standards-compliant REST APIs with OpenAPI docs. Use Node.js, Express, Django, or Spring Boot for high-performance endpoints.
GraphQL API Development
Design GraphQL schemas for flexible data querying. Use Apollo Server, GraphQL Yoga, and implement caching with Redis.
gRPC API Development
Implement gRPC services for low-latency, high-throughput communication. Use Protocol Buffers with Go, Python, or C++.
Webhook and Event-Driven API Development
Build webhook systems with delivery guarantees using SQS, RabbitMQ, or Kafka. Support retries with exponential backoff.
Third-Party API Integration Consulting
Integrate external APIs like Stripe, Salesforce, Twilio, or Slack. Handle rate limits, pagination, and error mapping.
API Gateway and Aggregation Layer
Create a single entry point for microservices using Kong, AWS API Gateway, or NGINX. Reduce client complexity.
Microservices API Architecture Design
Design decoupled API services with service mesh (Istio) and container orchestration (Kubernetes). Each service owns its data.
Real-Time API (WebSocket / SSE)
Build real-time data streams with WebSocket or Server-Sent Events. Use Socket.IO, Pusher, or custom protocol on WebSocket.
We build for every business type.
SaaS companies
Fintech firms
Healthcare organizations
Ecommerce brands
Enterprise platforms
Why Custom API Development Consultants Matter
A poorly designed API costs your team weeks in debugging and integration time.
IRPR's consultants have shipped 200+ production APIs handling millions of requests per day. Our APIs average 50ms response times and 99.9% uptime.
We use OpenAPI 3.0 for documentation, automated testing with Postman collections, and CI/CD pipelines on GitHub Actions. Every API is monitored with Datadog and Sentry.
Generic Dev Shop vs IRPR: The API Delivery Gap
Not all developers understand API contracts, error codes, and rate limiting from day one.
Generic agencies often hand bombed endpoints without documentation or error handling. They treat each API as a standalone script, not a reusable product.
IRPR builds APIs as products: OpenAPI specs are written before code, all endpoints include uniform error responses, and we ship with auto-generated client SDKs for Python, Node, and Java.
- No API contracts until week 6
- Inconsistent error formats (400, 500)
- No rate limiting or auth built in
- Documentation is an afterthought
- Unclear versioning strategy
- No staging environment for testing
- OpenAPI 3.0 spec delivered week 1
- Uniform error schema across all endpoints
- Built-in rate limiting with API keys
- Auto-generated docs with Swagger UI
- Semantic versioning from launch
- Staging and sandbox environments included
Our API Design and Delivery Process
Every API project follows a 4-phase framework from idea to release.
We start with an API first approach: define endpoints, schemas, and data flows before writing any production code. This eliminates integration surprises later.
Each phase includes a review with your team. You see working endpoints every 2 weeks, not just slides.
What Ships with Every Custom API Project
Your team gets more than endpoints. Every deliverable is production-ready from day one.
We hand over everything: source code, tests, documentation, and CI/CD pipelines. No black boxes.
- Complete source code in your GitHub repo
- OpenAPI 3.0 specification (YAML/JSON)
- Auto-generated interactive API docs (Swagger UI)
- Postman collection with all endpoints and example calls
- CI/CD pipeline with GitHub Actions and linting
- Load testing scripts (k6, Artillery)
- Error monitoring with Sentry
- Performance dashboards in Datadog
- Developer guide with integration examples
- Client SDK stubs for Python, Node, and Java
What we ship in this practice.
Fintech Payment Gateway API
Built a PCI-DSS compliant payment processing API for a fintech startup. Handles 10,000 transactions per minute with <100ms latency using Node.js, Express, Stripe API integration, and Redis caching. Reduced transaction failure rate by 40%.
Healthcare FHIR API for EHR Integration
Developed a FHIR R4 API to connect a telemedicine platform with Epic and Cerner EHR systems. Using Python FastAPI, HL7 FHIR SDK, and AWS HealthLake. Enabled real-time patient data sync saving doctors 2 hours per day.
SaaS Multi-Tenant API with Usage Tracking
Created a multi-tenant REST API for a SaaS analytics platform with per-customer rate limits and billing hooks. Tech stack: Django REST Framework, PostgreSQL, Redis, Stripe. Scaled from 10 to 500 tenants in 6 months without downtime.
Ecommerce Inventory Sync API
Built a real-time inventory sync API connecting an ecommerce brand's warehouse system to Shopify and Amazon Marketplaces. Uses WebSockets and RabbitMQ for event streaming. Cut inventory discrepancy reports from daily to real-time.
Real Estate MLS Data API
Developed a GraphQL API for a real estate platform aggregating MLS listings from 5 regional databases. Used Apollo Server, MongoDB, and AWS Lambda. Reduced listing update latency from 4 hours to 15 seconds.
Media Content Delivery API for Streaming
Designed a gRPC microservice API for a video streaming platform to manage transcoding workflows and content metadata. Go language, Protocol Buffers, RabbitMQ. Increased transcoding throughput by 3x.
Why teams hire us.
Fixed Price, Not Hourly
Every custom API project gets a fixed quote during the Roadmap phase (week 2). No hourly billing, no surprise invoices, no scope creep charges. You know the cost upfront.
Senior Engineers Only
Every IRPR consultant has 8+ years of production API experience. No juniors, no offshoring. Our team includes former AWS engineers and contributors to the OAuth 2.0 spec.
OpenAPI Spec Before Code
We write the OpenAPI 3.0 specification before writing any endpoints. Your team reviews design contracts in week 1, not week 6. Eliminates integration surprises.
Production Ready from Day One
Every API ships with CI/CD, monitoring, error tracking, auto-generated docs, and client SDK stubs. You don't need to hire a DevOps engineer to make it work.
HIPAA and PCI-DSS Compliance
IRPR has built APIs for healthcare and fintech clients requiring HIPAA and PCI-DSS compliance. Our code passes security audits before deployment. We run static analysis with SonarQube and dynamic scans with OWASP ZAP.
Full Code Ownership
You own 100% of the source code, documentation, and infrastructure. IRPR does not license or restrict. Handoff is complete: source in your repo, docs in your wiki, APIs in your account.
Idea → Roadmap → Product → Release.
Every engagement runs through the same four-stage pipeline. Predictable by design.
Questions clients ask first.
Related services and industries.
Ready to build? Let's talk.
30-minute discovery call. No deck. We'll tell you honestly what it takes, how long, and how much.