API Development

APIs that hold under load and document themselves.

API development at Empyreal Infotech means OpenAPI-first design with rate limiting, versioning, and OAuth 2.0 that handle production load without documentation gaps or concurrency failures.

OpenAPI specifications. Rate limiting that scales. Versioning that doesn't break clients. Authentication that works across integrations. Your API is reliable because the design happened first. Documented because the spec was written before the code.

For teams building integrations into their platform. For startups publishing APIs to partners. Founder-led API reviews. OpenAPI-first design.

Start an API conversationExplore our API methodology
OpenAPI-firstRate limiting99.95% uptime$55–80/hr
The Framework Decision

REST scales to infinity. GraphQL scales to clarity. The choice tree.

REST and GraphQL are not opposites. REST is a constraint that forces good boundary design. GraphQL is flexibility that lets clients ask for what they need. The question is not which is better. The question is: does your API scale through many integrations, or does it scale through a few power users asking for custom data shapes?

Most teams need both. REST for public APIs, GraphQL for internal tools. REST for webhooks, GraphQL for client apps. REST for rate-limited tier-based pricing, GraphQL for unlimited paid integrations. We start with this question. Not the framework.

Production API Infrastructure

Spec-first. Rate-limiting. Versioning that works.

OpenAPI Specifications

Spec written before code. API documented by design, not afterthought. Client SDKs generated from spec. Your spec is the contract.

Rate Limiting & Quotas

Tiered rate limits by integration. Token bucket algorithms. Quota management. Graceful degradation. Your API scales because the limits are designed in.

API Versioning

Semantic versioning strategy. Deprecation paths for old versions. Sunset dates communicated in headers. Breaking changes don't surprise partners.

Auth & OAuth 2.0

API key management. OAuth 2.0 for third-party integrations. Scoped permissions. Audit logs of who called what when.

How We Build APIs

Four decisions before the first endpoint.

01

Design the boundary

What lives inside your service. What lives outside. What gets versioned. What is stable. The contract is drawn first.

02

Specify with OpenAPI

Every endpoint. Every parameter. Every response. Spec-first design. Client SDKs generated. Documentation is auto-generated from the spec.

03

Implement inside the spec

Code builds the spec contract. Every response is spec-validated. Rate limits are part of the spec. Auth flows are documented.

04

Monitor in production

API telemetry. Rate limit behavior. Integration health. Breaking changes caught before partners report them.

Reality

Why APIs die under load.

Not because of the technology. Because rate limiting was bolted on after launch. Because versioning was not planned. Because the spec was written after the code was shipped. Because nobody documented the integration patterns and partners are asking "how do I use your API?" at 3 AM.

The API that survives scale is the one where the design happened first. Rate limits are not performance tuning. They are architecture. Versioning is not deployment strategy. It is a contract with every integration. Documentation is not marketing. It is the spec made visible.

Design for scale before you build for speed.

Proof

APIs that partners trust with critical workflows.

50+
Production APIs built
99.95%
Uptime across deployments

Fifty production APIs carrying traffic for payment systems, integrations, and critical workflows. Built on spec-first design. Built to hold under load. Built to scale without breaking partners.

Next Step

Your API conversation starts with the boundary.

Most teams build the API first and design the contract second. You do it backwards. You design the contract first, then build inside it. That is why your API scales.

Schedule a 45-minute API design sessionSee our API methodology
Questions

Frequently asked questions about our API development

Direct answers about how this engagement actually works. If your question is not here, ask Mohit directly.

Versioning, rate limiting, OAuth 2.0 flows, webhooks with idempotency, and OpenAPI specs that document themselves. We've shipped 50+ production APIs. Most junior-built APIs break under concurrency or fail silently when downstream services are down.
A production-grade REST or GraphQL API with authentication, error handling, and monitoring usually runs 150-250 hours. That's 4-7 weeks with a dedicated engineer. If you're adding APIs to an existing system, timeline is shorter.
Senior API engineers cost $45-55/hr. A 200-hour API project at $50/hr = $10,000. We price by scope: define your endpoints, data models, and security requirements, and we give you a fixed estimate.
Both. REST for straightforward integrations and public APIs. GraphQL when clients need flexible queries or you're consolidating multiple endpoints. We recommend based on your use case, not our preference.
Token bucket algorithms with Redis, IP-based throttling, and user-quota tracking. We also implement request signing for sensitive operations and monitor for suspicious patterns. OpenAPI specs document all limits so clients know what to expect.
Yes. You own all source code, git history, and OpenAPI specifications. We also leave you with postman collections, architecture diagrams, and runbooks for common operational tasks. Code review from the founder is included.

Have a different question? Email the team or read the full FAQ.