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✓ On-time delivery
+ Agile delivery
2-wk sprints
API Development Services

APIs Built for Security, Scale & Developer Experience

We design and build REST, GraphQL, and gRPC APIs — schema-first, documented, versioned, and secured with OAuth 2.0 from day one.

REST & GraphQL
OpenAPI 3.1
OAuth 2.0
100% IP Yours
Free first consultationNo commitment needed

API development

REST, GraphQL, gRPC

100%

code & IP yours from day one

typical API delivery
est.

4–8 wks

48h

Avg. Response Time

no surprises, ever

What are API development services?

API development services cover the design, build, documentation, and production deployment of application programming interfaces that connect systems, enable third-party integrations, and power mobile and web frontends. This includes REST API design with OpenAPI contracts, GraphQL schema design, gRPC service definitions, OAuth 2.0 authentication, rate limiting, versioning strategy, load testing, and developer portal documentation. A dedicated API team handles every layer from contract design to gateway configuration so your teams integrate reliably.

Our Services

API Development Services We Deliver

From simple REST APIs to enterprise integration platforms with developer portals.

01

REST API Design and Development

Consistent, versioned, and documented REST APIs with OpenAPI 3.1, idempotency, and clear error contracts.

02

GraphQL API Development

Schema-first GraphQL APIs with Apollo Server, subscriptions, DataLoader for N+1 prevention, and introspection docs.

03

gRPC API Development

High-performance binary gRPC APIs with Protobuf schema, code-generated clients, and bidirectional streaming.

04

API Security and Authentication

OAuth 2.0, JWT, mTLS, rate limiting, input validation, and OWASP API Security Top 10 review on every project.

05

API Gateway and Developer Portal

API gateway configuration (AWS, Kong, Traefik), developer portal with interactive documentation and sandbox credentials.

06

API Audit and Redesign

Review and redesign existing APIs for consistency, security gaps, versioning strategy, and performance bottlenecks.

Tech Stack

API Stack From Design to Production

API Styles
REST (OpenAPI 3.1)
GraphQL
gRPC / Protobuf
WebSockets / SSE
Backend Runtimes
Node.js (Fastify, Express)
Python (FastAPI)
Java (Spring Boot)
Go (Chi, Gin)
Auth & Security
OAuth 2.0 / OIDC
JWT
mTLS
API Keys + HMAC
Documentation
OpenAPI / Swagger
GraphiQL / Apollo Sandbox
Stoplight
Postman Collections
Gateway & Infra
AWS API Gateway
Kong
Traefik
Nginx
Testing
Supertest
REST Assured
k6 (load)
Pact (contract)
Why Good API Design

The Contract That Every Consumer Integration Depends On

A stable, versioned API contract prevents downstream consumer breakage
OpenAPI documentation reduces integration time for every new consumer
Idempotent write operations make retry logic safe and predictable
Rate limiting and input validation prevent abuse before it reaches your database
OAuth 2.0 and JWT give you auditable, revocable authentication without shared secrets
GraphQL eliminates over-fetching so mobile clients receive only the data they display
gRPC reduces inter-service latency compared to REST for high-frequency internal calls
Contract tests catch API breaking changes before they break consumers in production
Our Process

How We Build APIs

A structured delivery process from contract design to gateway configuration and handover.

01

API Design and Contract Definition

We define the OpenAPI or GraphQL schema before any code is written, agree on naming conventions, versioning strategy, and error format with all consumer teams.

02

Security Architecture

Auth flow, token lifecycle, rate limiting tiers, and access control model are designed and agreed before the first endpoint is built.

03

Core API Build in Sprints

Endpoints are built iteratively against the agreed schema with integration tests validating correctness at every milestone.

04

Documentation and SDK Generation

OpenAPI spec, interactive Swagger UI, Postman collection, and optional SDK generation are produced from the live implementation.

05

Load Testing and Performance Validation

k6 or Locust load tests verify the API handles target concurrency at acceptable latency before production.

06

Gateway, Monitoring, and Handover

API gateway configuration, rate limit tiers, error alerting, access log dashboards, and full API documentation handover.

Indicative Pricing

API Project Investment Ranges

Fixed-price scopes for common API engagement types.

EngagementScopeInvestment (USD)
REST APIAuth, CRUD, OpenAPI docs, rate limiting$8,000 – $22,000
Full API PlatformMultiple resources, third-party integrations, portal$25,000 – $70,000
Enterprise API ProgrammePartner integrations, multi-tenant, compliance$50,000 – $140,000+

Ranges are indicative. Final pricing depends on resource count, integration complexity, and compliance requirements. Get a fixed-price quote after a scoping call.

Why CodeShiper

Why Teams Choose Us for API Development

Six reasons API projects succeed with our team.

01

Schema-First Design

We define the OpenAPI or GraphQL contract before writing code. Consumer teams can start building against the spec while the API is in development.

02

Security Is Not Optional

OAuth 2.0, rate limiting, input validation, and OWASP API review are in scope on every project — not charged as extras.

03

Documentation as a Deliverable

Every API ships with accurate, interactive OpenAPI documentation. Undocumented APIs get misused; we make sure yours is not.

04

Contract Testing

Pact-based contract tests ensure that API providers and consumers agree on the contract in CI — not discovered via a production incident.

05

Load Testing Before Go-Live

We run k6 load tests against your target concurrency numbers before any production deployment. No surprises on launch day.

06

Versioning and Deprecation Strategy

Every API we build ships with a versioning contract and deprecation policy so you can evolve the API without breaking consumers.

100%
IP ownership from day one
OpenAPI
Docs delivered with every API
48 h
Average response time
98%
Client satisfaction rate
FAQ

Common Questions About API Development

What is API development and why does my business need it?
API (Application Programming Interface) development is the design and build of structured communication contracts between software systems. Every modern business that wants its systems to talk to each other — internal apps to external tools, mobile apps to backend servers, third-party payment processors to your platform — needs well-designed APIs. A poorly designed API is one of the most expensive technical decisions to undo: every consumer integration is built on your contract, and breaking changes break everyone downstream.
REST vs GraphQL vs gRPC — which should we use?
REST is the right default for most public-facing APIs, mobile backends, and third-party integrations — it is widely understood, easily cached, and tooled by every client in every language. GraphQL is the right choice when multiple clients (web, mobile, third-party) need different data shapes from the same backend, or when over-fetching and under-fetching are real performance problems. gRPC is the right choice for internal service-to-service communication, especially when you need high throughput, streaming, or polyglot services — its binary protocol and code-generated clients make it significantly faster than REST for internal calls.
What makes an API well-designed?
A well-designed API is consistent (naming, error formats, and response shapes are predictable), versioned (consumers can upgrade on their own timeline), documented (OpenAPI/Swagger or GraphQL schema with examples), idempotent for write operations (retrying the same request does not create duplicate side effects), and honest about failure modes (clear error codes and messages, not generic 500s). Most API design problems come from inconsistency and undocumented implicit contracts, not from the choice of REST vs GraphQL.
How do you handle API authentication and security?
For public APIs, we implement OAuth 2.0 with the appropriate grant type (Authorization Code for user-facing, Client Credentials for machine-to-machine). For internal APIs, API keys or mTLS (mutual TLS) are common. Every API gets input validation at the boundary, rate limiting to prevent abuse, and HTTPS-only enforcement. Sensitive endpoints get additional controls — short-lived tokens, refresh token rotation, and audit logging. We follow OWASP API Security Top 10 as the baseline checklist.
What is API versioning and how should we do it?
API versioning is how you introduce breaking changes without breaking existing consumers. The most common approach is URL versioning (/api/v1/, /api/v2/) — explicit, easy to route, visible in logs. Header-based versioning (Accept: application/vnd.api+json; version=2) is cleaner but harder to cache and debug. For GraphQL, the standard advice is to avoid versioning by evolving the schema non-breakingly with deprecation. We recommend URL versioning for REST and a clear deprecation policy with a sunset header before removing any endpoint.
How do you document APIs?
For REST APIs, we generate OpenAPI 3.1 documentation from code annotations or schema-first definitions. The generated spec drives Swagger UI for interactive documentation, Postman collection generation, and SDK generation for common languages. For GraphQL, the schema is self-documenting via introspection, and we add GraphiQL or Apollo Sandbox for interactive exploration. Documentation is treated as a deliverable, not an afterthought — undocumented APIs get abandoned or misused.
How do you design an API for a third-party integration or partner?
Third-party and partner APIs require more stability guarantees than internal APIs. We apply a stricter versioning contract, define explicit deprecation timelines (typically 12+ months), publish a changelog, and provide sandbox environments with test credentials. We design idempotency keys for write operations so retry logic does not create duplicates. We also consider the developer experience explicitly — the easier the API is to integrate from a client, the less support burden it creates.
How do you test APIs?
We write unit tests for business logic, HTTP integration tests using Supertest (Node.js), MockMvc (Spring), or httptest (Go) against real server instances, and contract tests using Pact or similar to verify that API consumers and providers agree on the contract. Load tests with k6 or Locust verify the API handles target concurrency before any production deployment. We do not accept "it works in Postman" as a test strategy.
What is an API gateway and do we need one?
An API gateway is a reverse proxy that sits in front of your APIs and handles cross-cutting concerns: authentication, rate limiting, request routing, SSL termination, logging, and sometimes response caching. You need one when you have multiple services that clients should access through a single entry point, or when you want to enforce security and rate limiting consistently without implementing it in every service. AWS API Gateway, Kong, and Traefik are common choices depending on your infrastructure.
What does an API development project typically cost?
A simple REST API with auth, CRUD endpoints, and OpenAPI documentation typically costs $8,000 to $22,000. A full API platform with multiple resource types, third-party integrations, a developer portal, and SDK generation runs $25,000 to $70,000. An enterprise API with complex business logic, multi-tenant architecture, advanced rate limiting, and a partner integration programme is typically $50,000 to $140,000 depending on scope and compliance requirements.

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