API Development

APIs that power your ecosystem.

Zarsco builds scalable, secure, and well-documented APIs that connect your products, partners, and internal systems. From RESTful services to GraphQL and WebSocket APIs, our backend engineers build APIs designed for reliability and developer experience.

Developer-First Design

Clear, consistent APIs with comprehensive OpenAPI documentation and SDKs.

Enterprise Security

OAuth 2.0, API keys, rate limiting, and IP allowlisting for secure access.

High Performance

APIs handling thousands of requests per second with sub-100ms response times.

Versioning & Stability

Semantic versioning and backward-compatible changes for API consumers.

What we do for you

All Industries

Third-Party Integrations

APIs connecting your platform with Salesforce, HubSpot, Shopify, and hundreds more.

Mobile

Mobile App Backend

RESTful or GraphQL APIs powering iOS and Android applications.

Technology

Microservices Architecture

Internal APIs enabling microservices to communicate reliably at scale.

Platform / SaaS

Partner API Program

Public APIs for third-party developers to build on your platform.

Analytics / Finance

Data APIs

APIs for real-time and batch data access with streaming support.

All Industries

Webhook System

Event-driven APIs that push real-time updates to external systems.

Everything included in our API Development service

We handle every aspect from strategy to launch so you can focus on outcomes, not execution.

  • RESTful API design with OpenAPI 3.0 spec
  • GraphQL API with query optimization
  • WebSocket for real-time features
  • OAuth 2.0 and API key authentication
  • Rate limiting and throttling
  • API versioning strategy
  • Comprehensive Postman/Swagger documentation
  • SDK generation for JavaScript, Python, and more

Frequently Asked Questions

REST vs GraphQL — which should I choose?

REST is simpler, better-cached, and widely understood — great for most use cases. GraphQL excels when clients need flexible queries or when you're supporting many different client types. We'll recommend the right choice for your specific architecture.

How do you handle API security?

We implement OAuth 2.0 or API key auth, HTTPS only, input validation, SQL injection prevention, rate limiting, CORS policies, and audit logging for all API requests.

Do you write API documentation?

Yes. We provide OpenAPI 3.0 (Swagger) specifications, Postman collections, integration guides, and code examples. Good documentation is non-negotiable for any API we build.

Can you build APIs that integrate with third-party services?

Yes. We have experience integrating with hundreds of third-party APIs — Stripe, Twilio, SendGrid, Salesforce, HubSpot, AWS services, Google APIs, and many more.

Ready to get started with API Development?

Book a free consultation call. Our experts will assess your needs and outline a clear plan.