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Make your systems
talk to each other.

Robust, documented REST APIs built from scratch — and third-party integrations that connect the tools you already use. Orders flowing to fulfilment, leads into your CRM, data where it belongs, automatically.

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Is this you?

Copy-paste between tools
is a job nobody wanted.

PROBLEM 01

Systems that don't speak

Your store, CRM, accounting, and shipping tools all hold pieces of the truth — and someone manually shuttles data between them daily.

PROBLEM 02

Partners need access

Vendors and partners want to connect to your data programmatically, and you have no safe way to let them. A proper API is that way.

PROBLEM 03

The fragile Zapier tower

Automations held together with no-code tools that break silently and bill by the task. Real integrations are sturdier and cheaper at scale.

The Nexo way

Documented. Secured. Boring in the best possible way.

APIs should be the most reliable part of your stack. Mine come with authentication, rate limiting, clear documentation, and error handling that fails loudly instead of silently.

What's included

Everything you need.
Nothing you don't.

Custom REST API development

Endpoints designed around your data and workflows, built on solid foundations.

Third-party integrations

Stripe, CRMs, email platforms, shipping carriers, accounting tools — connected properly.

Authentication & security

API keys, OAuth, rate limiting, and access controls — partner access without exposure.

Webhooks & automation

Event-driven flows: when X happens in one system, Y happens everywhere it should.

Documentation included

Clear docs any developer can pick up — you're never locked to me.

Monitoring & logging

Know what's flowing, catch what's failing, with logs that make debugging fast.

How it works

From first message
to connected systems.

Map the data flow

We chart what needs to move where, when, and what happens when things go wrong.

Fixed quote

Endpoints, integrations, and timeline priced in writing within 48 hours.

Build & test hard

Integrations tested against real-world mess: retries, timeouts, malformed data, edge cases.

Deploy with docs

Live, monitored, documented — with handover notes your future developers will thank you for.

PRICING

From $1,500, fixed

Single integrations from $1,500; full custom APIs typically $3,000–$10,000. Fixed quote before I start — no surprise invoices, no lock-in contracts.

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PROOF

Wired into real stores

The e-commerce builds in my portfolio run on integrations — payments, shipping, inventory — moving data reliably every day.

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API questions? Straight answers.

How much does API development cost?

Single third-party integrations start at $1,500; complete custom REST APIs typically run $3,000–$10,000 depending on endpoints and complexity. Fixed quote upfront, always.

Can you connect my store to my other tools?

Yes — that's the most common request. Orders to fulfilment, customers to CRM, sales to accounting: connected once, running automatically.

Is a custom integration better than Zapier?

For light workflows, no-code tools are fine. Once volume grows or reliability matters, custom integrations win: no per-task fees, no silent failures, and logic no-code tools can't express. I'll tell you honestly which your case needs.

Will other developers be able to work with your API?

Yes — everything ships with clear documentation and standard conventions. No lock-in by obscurity.

Can you fix or extend an existing API?

Usually. I'll review what's there and give you a straight assessment — extend, refactor, or rebuild — before anything is spent.

Related services

APIs are the plumbing behind web apps, AI automations, and serious e-commerce operations.

Web App Development →AI Integration →E-commerce Websites →

Tired of being
the human API?

Tell me which systems should talk. I'll map the connection and price it fixed.

Get in Touch →