Most "we need automation" requests are actually a missing integration.
When two systems don't talk to each other, someone ends up manually copying data between them — orders from a website into an inventory system, leads from a form into a CRM, payments into an accounting tool. Nexa Codex builds the API connections that remove that manual step.
We work with existing third-party APIs (payment gateways like Razorpay, CRMs, WhatsApp Business, shipping providers) and, where none exists, build custom APIs so your own systems can be integrated by anyone in the future.
Every integration is documented and tested against edge cases — failed payments, duplicate webhooks, rate limits — not just the happy path.
What an API & integration project includes
- Custom REST API development for your own systems
- Payment gateway integration (Razorpay and others)
- CRM, ERP and accounting tool connections
- WhatsApp Business, SMS and email API integration
- Webhook handling with retry and failure logic
- API documentation for future developers
What makes an integration reliable, not just functional in testing.
The details that matter once real data — and real edge cases — start flowing through.
Connects the tools you already use
Payment gateways, CRMs, shipping and messaging providers integrate through their APIs, no manual re-entry required.
Custom APIs where none exist
When two of your own systems need to talk and no off-the-shelf integration exists, we build the API layer that connects them.
Handles failure cases
Failed payments, duplicate webhooks and rate limits are handled explicitly, not left to silently drop data.
Documented for the future
Every integration ships with documentation, so a future developer — ours or yours — can maintain or extend it without reverse-engineering the code.
Tested against real load
Integrations are load-tested against realistic traffic, not just verified once in a staging environment.
Secure credential handling
API keys and tokens are stored and rotated following standard security practice, not hardcoded into a config file.
API development & integration questions
What kinds of systems can you integrate?
Most systems with a public API — payment gateways, CRMs, ERPs, WhatsApp Business, shipping/logistics providers, accounting tools and custom internal software.
What if the tool we use doesn't have a public API?
Some tools support integration through webhooks, CSV exports/imports, or partner-only APIs — we assess what's available and find the most reliable connection method, or recommend a swap if there's genuinely no way in.
How do you handle failed payments or dropped webhooks?
Integrations include retry logic and failure handling for exactly these cases, plus logging so a dropped event can be identified and reprocessed instead of silently disappearing.
Can you build a public API for our own product?
Yes — if you need to expose your own data or functionality to partners or a future app, we design and build a documented REST API for that purpose.
More from Nexa Codex
Tired of manually moving data between two tools?
Tell us which systems need to talk to each other — we'll scope the integration.