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Custom Software

API Development & Integration

REST, GraphQL, gRPC — built in PHP, Go, Spring Boot, Node.js, or Quarkus. Custom API gateways, OAuth2 auth servers, LLM integration APIs, and third-party integrations. Contract-first, fully documented, production-tested.

REST GraphQL gRPC Spring Boot Go Lang Node.js PHP OAuth2
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Secure API gateway connecting web and mobile clients to GraphQL, webhooks, identity, databases and microservices

Secure integration gateway

Contracts · identity · routing · observability

Contract first

OpenAPI documented

OAuth 2.0

Secure by design

Real time

Webhooks & events

API Specialisations

Every API type, every technology stack

Spring Boot APIs

Java 21 Spring WebMVC JPA Maven

Enterprise-grade REST and reactive APIs using Spring Boot 3 with Java 21. We build structured multi-module projects with Spring Security, JPA repositories, Flyway migrations, and OpenAPI 3 documentation via SpringDoc. Deployed to AWS ECS or Kubernetes.

Spring WebFlux (Web Reactive)

Reactive Streams R2DBC Project Reactor

Non-blocking reactive APIs using Spring WebFlux and Project Reactor — ideal for streaming data, high-concurrency microservices, and WebSocket-heavy backends that need to handle thousands of concurrent connections on minimal infrastructure.

Go (Golang) APIs

Go 1.22 Gin / Fiber SQLC gRPC

Blazing-fast microservices in Go using Gin or Fiber for HTTP APIs and gRPC for internal service-to-service communication. Go's compile-time safety and low memory footprint make it ideal for high-throughput payment processors and real-time APIs.

Quarkus APIs

Quarkus GraalVM Panache RESTEasy

Cloud-native Java APIs with Quarkus — compiling to native executables with GraalVM for sub-100ms startup times and minimal memory footprint. Perfect for serverless deployments and microservices with tight cold-start requirements.

Node.js APIs

Node 20 Fastify Prisma tRPC

High-performance Node.js APIs using Fastify (2× faster than Express) with TypeScript, Prisma ORM, and tRPC for end-to-end type safety between a Next.js frontend and Node backend. Ideal for real-time apps with WebSocket or SSE requirements.

PHP APIs (Laravel & Slim)

Laravel 11 Slim 4 Sanctum Passport

Laravel REST and GraphQL (Lighthouse) APIs — our most common stack for Pakistani market applications. Also Slim 4 for lightweight microservices where the full Laravel framework would be overkill. OpenAPI 3.1 spec generated from code annotations.

GraphQL APIs

GraphQL Apollo Lighthouse DataLoader

Schema-first GraphQL APIs with Apollo Server (Node.js) or Lighthouse (Laravel). DataLoader patterns prevent N+1 query problems. Depth limiting, query complexity scoring, and persisted queries protect against abusive clients.

gRPC & Protobuf APIs

gRPC Protocol Buffers Go Java

Binary-protocol gRPC APIs for internal microservice communication — 5–10× smaller payloads than JSON REST and strongly-typed contracts enforced by Protobuf schemas. Used for high-frequency inter-service calls in distributed systems.

WebSocket & Streaming APIs

WebSocket SSE Socket.io Laravel Echo

Real-time bidirectional communication for chat, live dashboards, collaborative tools, and notification systems. Server-Sent Events for one-way streaming (AI output, live feeds). Laravel Echo + Pusher or Soketi for event broadcasting.

Infrastructure

Custom API Gateway

A custom API gateway sits in front of all your backend services and handles the cross-cutting concerns that every API needs but none should implement individually: authentication, rate limiting, request routing, payload transformation, logging, and analytics. Instead of duplicating this logic across 10 microservices, you implement it once in the gateway.

We build custom gateways using Go (for maximum throughput) or Laravel (for rapid development) depending on your scale requirements. The gateway proxies to downstream services, validates JWTs or API keys, enforces per-consumer rate limits, transforms request and response payloads when needed, and emits structured logs to your observability stack. An admin dashboard shows per-consumer usage, error rates, and latency percentiles in real time.

JWT / API key validation
Per-consumer rate limiting
Request routing & load balancing
Payload transformation (req & res)
Circuit breaker pattern
Request/response logging
Developer API key portal
Usage analytics dashboard
Security

OAuth2, JWT & API Security

API security is not a bolt-on. We implement the correct authentication mechanism for your use case from day one — and choose it deliberately, not by default.

OAuth2 Authorization Server

Full OAuth2 server (Authorization Code, Client Credentials, PKCE) using Laravel Passport or Spring Authorization Server — with scopes, refresh tokens, and token introspection.

JWT Bearer Tokens

Stateless JWT authentication with RS256 signing, short expiry, refresh token rotation, and token blacklisting for logout. JWKS endpoint for public key distribution.

API Key Management

Self-service API key issuance with hashed storage, last-used timestamps, per-key permission scopes, and admin revocation — suitable for B2B API products.

mTLS for Service-to-Service

Mutual TLS for internal microservice APIs — each service presents a certificate; the gateway validates both sides. No shared secrets over the wire.

OWASP API Top 10 Hardening

We audit and harden against broken object-level auth, mass assignment, security misconfiguration, unrestricted resource consumption, and the full OWASP API Security Top 10.

Integrations

Third-party API & LLM integrations

Third-Party API Integration

We integrate any third-party service that has a documented API — handling authentication, webhook verification, error handling, retry logic, and idempotency so your integration is robust from day one.

Payments
JazzCash, EasyPaisa, Stripe, PayPal, HBL, Meezan Bank
Communications
Twilio SMS, SendGrid, Mailgun, Firebase FCM, WhatsApp Business API
CRM & ERP
HubSpot, Salesforce, SAP, Odoo, Zoho, Pipedrive
Mapping & Logistics
Google Maps, Mapbox, HERE Maps, Pakistan Post, TCS, Leopards
Social & Identity
Google OAuth, Facebook Login, LinkedIn, Apple Sign-in, NADRA VERISYS
Finance & Tax
FBR API, SBP reporting, SECP filings, Open Banking (PSD2)

What we handle for every integration

  • Credential storage in Secrets Manager (never .env files)
  • Webhook signature verification & idempotent processing
  • Exponential backoff retry on transient failures
  • Daily reconciliation job to catch missed webhooks
  • Test coverage: happy path + all documented error codes
  • Sandbox → staging → production environment separation

LLM Integration API

We build APIs that expose LLM capabilities to your product — wrapping OpenAI, Anthropic Claude, Google Gemini, or self-hosted open-source models behind a clean, versioned API your frontend team can consume without understanding prompt engineering.

Chat Completion APIs

Multi-turn conversation endpoints with system prompt management, conversation history persistence, context window management, and token usage tracking per conversation.

RAG (Retrieval-Augmented Generation)

Document ingestion pipelines that chunk, embed, and store your content in a vector database (Pinecone, pgvector, Qdrant). Query endpoints retrieve relevant context before generation.

Streaming Completion

Server-Sent Events endpoint that streams LLM tokens to your frontend as they are generated — eliminating the perceived latency of waiting for a full response before rendering.

Function Calling / Tool Use

LLM agents that call your internal APIs as tools — looking up customer records, querying stock levels, booking appointments — with structured JSON output and error handling.

Vision & Multimodal APIs

Endpoints that accept image uploads and return structured JSON analysis using GPT-4o Vision or Claude — for document OCR, product image classification, and visual QA pipelines.

LLM API Gateway (Cost & Safety)

Proxy layer that caches identical prompts, enforces per-user token budgets, redacts PII before sending to third-party LLMs, logs all prompts/completions for audit, and falls back to a cheaper model when the primary is unavailable.

APIs that other teams love to consume

A poorly designed API is a multiplier of technical debt — every integration partner inherits your mistakes. We design APIs contract-first: the OpenAPI 3.1 specification is written and reviewed before the first endpoint is implemented. Resource naming is consistent, response formats are predictable, and error responses include enough context to debug without reading your source code.

We follow REST conventions correctly — not just HTTP verbs and JSON, but proper resource nesting, consistent pagination, meaningful HTTP status codes, and hypermedia links where useful. For GraphQL APIs, we design schemas that balance consumer flexibility with performance constraints, using DataLoader to prevent N+1 queries and depth limits to protect against abuse.

Choosing the right technology

Technology Best for Throughput
PHP / Laravel Rapid dev, CRUDs, Pakistani market apps ⭐⭐⭐
Node.js / Fastify Real-time, streaming, JS full-stack teams ⭐⭐⭐⭐
Go / Gin High-throughput microservices, fintech ⭐⭐⭐⭐⭐
Spring Boot Enterprise Java, complex domain models ⭐⭐⭐⭐
Spring WebFlux Reactive / non-blocking, streaming data ⭐⭐⭐⭐⭐
Quarkus Native serverless, cloud-native Java ⭐⭐⭐⭐⭐
GraphQL (any lang) Flexible data fetching, BFF layer ⭐⭐⭐
gRPC (Go / Java) Internal microservice, binary efficiency ⭐⭐⭐⭐⭐

Core capabilities

Contract-first OpenAPI 3.1 design
RESTful, GraphQL & gRPC endpoints
OAuth2 / JWT / API key authentication
Per-route rate limiting & throttling
URI versioning strategy (v1, v2)
Integration & contract test suites
Swagger UI & Postman collection
Webhook dispatch & verification
Idempotency keys for safe retries
Pagination (cursor & offset)
Filtering, sorting & field selection
Multi-language SDK generation

Frequently asked questions

REST suits simple, well-defined CRUD APIs with a small number of known consumers. GraphQL is better when different consumers (web, mobile, third-party) need different shapes of data from the same backend, or when you are building a BFF aggregation layer.
Depends on your team and requirements. PHP/Laravel is our default for rapid development and Pakistani market context. Go is ideal for high-throughput microservices. Spring Boot suits Java-heavy enterprise environments. Node.js/Fastify fits real-time and streaming APIs.
Every API ships with an OpenAPI 3.1 specification generated from code annotations (auto-kept in sync), a hosted Swagger UI, and an importable Postman collection your QA and integration partners can use immediately.
Yes. We build gateways in Go or Laravel with request routing, JWT validation, per-consumer rate limiting, payload transformation, circuit breakers, structured logging, and a developer portal for self-service API key management.
URI versioning (/api/v1, /api/v2) and a documented deprecation policy — consumers get at minimum 6 months notice before a version is sunset, with migration guides for every breaking change.
Yes. We build developer portals with self-service API key creation, usage analytics, webhook subscription management, tiered rate limits, and sandbox environments for testing without impacting production data.
Performance

Production APIs built for real traffic

An API that works in development and breaks under production load is worse than no API at all — it creates incidents, damages consumer trust, and is hard to fix under pressure. We load-test every API before launch using k6 or Gatling, profiling under realistic concurrent request patterns to identify bottlenecks before they reach production.

The key performance levers we apply: database query optimisation with EXPLAIN ANALYZE on slow queries, Redis caching for expensive aggregations, connection pooling (PgBouncer for PostgreSQL), async processing for non-blocking responses, and horizontal scaling behind a load balancer. Go and Spring WebFlux APIs get non-blocking I/O by design; PHP and Node.js APIs use queue workers to offload heavy tasks.

< 20ms
P50 latency (cached endpoints)
Redis hit, no DB query required
< 150ms
P99 latency (DB-backed endpoints)
Indexed queries, connection pooling
50,000+
Req/s (Go API, 2-core server)
k6 load test, no cache warm-up
5,000+
Req/s (Laravel Octane / FrankenPHP)
Sustained load, Redis-cached responses
99.95%
Uptime SLA (AWS multi-AZ)
Health-check-driven failover < 30s
100%
Endpoints with integration tests
Including error codes and edge cases
Our process

From contract to consumer-ready — the API development roadmap

Requirements & Consumer Analysis

Week 1

We interview every API consumer (frontend teams, mobile devs, third parties) to document what data shapes they need, what operations matter, and what SLA they require. This prevents rebuilding endpoints after handover.

OpenAPI / Schema Contract Design

Week 1–2

The API contract (OpenAPI 3.1 for REST or GraphQL schema for GraphQL) is written and reviewed before a single line of implementation code. All stakeholders sign off on the contract — it is the shared source of truth.

Architecture & Tech Stack Decision

Week 1–2

Database design, authentication strategy (OAuth2 / JWT / API keys), caching topology, rate limiting approach, and queue architecture are designed before development. Technology choice (Go, Spring Boot, Laravel, Node) is finalised here.

Implementation (Sprint-based)

Weeks 2–N

Development in 2-week sprints. Each sprint delivers a working set of endpoints deployed to the staging environment, with integration tests proving they match the contract. You test against the real API, not mocks.

Testing & Contract Verification

Each sprint

Integration tests for all endpoints (happy path + error codes), contract tests against the OpenAPI spec using Dredd or Spectral, load tests with k6, and security scans for OWASP API Top 10 vulnerabilities.

Documentation & SDK Generation

Final sprint

Swagger UI hosted alongside the API, Postman collection exported and versioned, SDK generation (TypeScript, Python) if required, and a developer onboarding guide with code examples for every endpoint.

Production Deployment & Monitoring

Go-live

Blue-green deployment, rate limit tuning, CloudWatch / Prometheus alerting on error rate and P99 latency, and a 30-day hypercare window where we monitor and fix any production issues immediately.

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