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Services > API Integration

APIs that connect
your business.

Custom API development, third-party integrations, and middleware that makes your systems talk to each other — reliably.

What We Build

The full API integration stack.

From custom API design to legacy system connectors — we build the integration layer that makes your tech stack actually work together.

Custom API Development

RESTful and GraphQL APIs designed for your business logic. Versioned, documented, and built to last. We spec the API contract first — endpoints, authentication, data models, error responses — then build to that contract so your frontend and third-party partners can integrate with confidence.

Third-Party Integration

Connect CRM, ERP, marketing, e-commerce, and payment platforms. We've integrated hundreds of APIs — we know where the documentation lies, which endpoints are unreliable, and how to build connectors that hold up when the upstream service has an outage.

Webhook Orchestration

Real-time event-driven architecture. Receive, transform, and route webhooks across your stack with retry logic and dead-letter queues.

Middleware & iPaaS

Custom middleware for complex data transformation. When Zapier or Make can't handle it, we build the bridge in Node.js or Python.

API Strategy & Documentation

OpenAPI specs, Postman collections, developer portals, and versioning strategy. APIs your team — and partners — can actually use.

Legacy System Integration

Connect modern SaaS to legacy on-prem systems. SOAP-to-REST translation, database connectors, and file-based integration without a full rewrite.

Rate Limiting & Security

API key management, OAuth 2.0, JWT authentication, rate limiting, and request validation. Security built into the API layer, not bolted on.

API Monitoring & Observability

Latency tracking, error rate dashboards, uptime monitoring, and SLA alerting. Know when an upstream API degrades before your users do.

Who This Is For

Built for teams with too many disconnected systems.

API integration pays off fast when data silos are costing your team time, accuracy, or visibility. Here's who we help most.

CTOs and VP Engineering building connected systems

You have 10+ tools in your stack and none of them share data natively. You need an integration layer that's maintainable, observable, and doesn't require a new hire to understand.

Companies experiencing data silos

Sales sees one version of the customer. Finance sees another. Operations has a third. You need a single source of truth — and that starts with proper integrations between your systems.

Teams building partner and customer-facing APIs

You're exposing data or functionality to external developers, partners, or customers. You need an API that's well-documented, versioned, and reliable — one that builds trust.

Companies with legacy systems that need to modernize

You can't replace the legacy system overnight, but you can build an abstraction layer on top of it. We create connectors that let modern tools work with legacy infrastructure — no big-bang migration required.

Our Process

From system audit to production integration.

01

Audit

We map your current system landscape — every tool, API, data flow, and integration point. We identify where data gets stuck, where manual handoffs happen, and what the integration priorities should be.

02

Design

We produce an API contract and integration architecture: endpoints, authentication patterns, data models, error handling, and versioning strategy. You review before we write a line of code.

03

Build

We develop the APIs and connectors against the agreed spec. Every integration includes error handling, retry logic, idempotency keys, and comprehensive logging. Tests are written alongside the code, not after.

04

Monitor

We deploy with observability from day one — latency dashboards, error rate alerts, and uptime monitoring. We provide documentation, Postman collections, and a handoff package so your team can maintain the integration.

Why Corsox

API expertise without the enterprise agency price

We've built integrations for Salesforce, HubSpot, Shopify, AWS, and hundreds of other platforms. We know which APIs break, where the documentation is wrong, and how to design integrations that survive versioning changes. US entity for contracting, LATAM engineering for execution.

Contract-first development

OpenAPI specs reviewed and approved before any code is written

LATAM engineering for speed and cost

Senior API engineers — 40–60% less than US agency rates

Common Questions

Questions we hear about API integration.

What APIs have you integrated before?

Hundreds — including Salesforce, HubSpot, Shopify, Stripe, QuickBooks, NetSuite, Twilio, SendGrid, AWS services, Azure services, and many industry-specific platforms. If it has a public API (or even just a SOAP endpoint), we've likely worked with something similar.

REST vs GraphQL — which should we use?

REST for simple CRUD operations and broad compatibility — it's universally understood, easier to cache, and simpler to document for external partners. GraphQL for complex data requirements where clients need to request exactly what they need — ideal for mobile apps, dashboards, and scenarios where over-fetching is a performance problem. We design the right approach for each use case.

How do you handle API failures and downtime?

Circuit breakers, exponential backoff, dead-letter queues, and monitoring with alerts. We design for failure because third-party APIs will fail — scheduled maintenance, rate limit hits, unexpected outages. Your workflows shouldn't cascade-fail when an upstream API goes down. Every integration we build includes failure handling as a first-class concern, not an afterthought.

Ready to connect your tech stack?

Tell us which systems need to talk to each other. We'll audit your current integrations, identify the gaps, and build API connections that are reliable, documented, and built to last.