System api integration

Systems & API Integration

System Integration Services That Connect the Tools You Already Use

We connect your CRM, accounting software, and everyday tools so information moves automatically between them — no more copying data by hand from one system to another.

Why DIY breaks

The Zapier Flow That Worked Fine Until It Didn't

A CRM integration that quietly stops syncing doesn't announce itself.

Most businesses don’t start with a system integration services provider, they start with a no-code tool and a weekend project. That works, until a field name changes upstream, a rate limit gets hit during a busy month, or the person who built it leaves the company and nobody knows how it works. You just find stale customer data three weeks later, after it’s already cost you something.

Custom API development isn’t about building something fancier than Zapier or Make. It’s about building something that’s monitored, documented, and doesn’t depend on one person remembering how it works.

WHAT WE CONNECT

Five Areas We Focus On

Your CRM should be the single source of truth for customer data — but only if it actually stays in sync with your invoicing tool, your support platform, and everything else that touches a customer record. CRM integration keeps every system updated automatically, so nobody's manually copying a new contact into three different places.

Xero integration services and QuickBooks integration services connect your books directly to your CRM, invoicing, and payment tools — so a new sale, an invoice, or a payment updates everywhere it needs to, without someone re-entering it.

Not every tool has an off-the-shelf connector. As an API integration company, we build custom API development for the specific tools in your stack that don't — matched to what your systems can actually handle, not a generic template.

Legacy system integration and ERP integration services are two of the areas most automation agencies avoid, because older systems don't always have modern APIs. We specifically work with these — connecting the tools you're not planning to replace anytime soon.

Google Workspace automation, Microsoft Teams, Slack, and the smaller tools your team relies on daily — connected so information doesn't need manual syncing between them either.

Fit check

Built for Businesses Running on Tools That Don't Talk to Each Other

If your CRM, accounting software, and everyday apps each work fine on their own — but someone on your team is the one manually keeping them in sync — this is built for you. We’re not a SaaS integration agency trying to sell you a new platform to replace what you have. We build the connections between the tools you’ve already chosen.

CRM

YOU

Copy · Paste · Repeat

Accounting

So your team stops being the integration layer between them.

Still copying data between two systems?

A no-pressure call to work out which connections are worth building first.

STACK

Fits Into the Tools You Already Use

We build on top of your existing stack — not a replacement for it.

30 Integrations · All categories

HubSpot CRM, marketing and sales in one platform

Pipedrive Sales-first CRM built for small teams

Salesforce Enterprise CRM and customer platform

GoHighLevel All-in-one CRM built for agencies

Zoho CRM CRM inside the wider Zoho suite

Monday.com Work management with CRM boards

Xero Cloud accounting for small business

QuickBooks Accounting and bookkeeping software

FreshBooks Invoicing and accounting for services

Sage Accounting and payroll software

Zoho Books Online accounting in the Zoho suite

Wave Free accounting for small business

n8n Source-available workflow automation

Zapier No-code automation between apps

Make Visual, scenario-based automation

Power Automate Microsoft workflow automation

Pipedream Developer-first integration platform

Workato Enterprise integration and automation

Proof

What Clients Say

GUARANTEE

Our Guarantee

Connected, without being locked in

An integration is only worth having if it keeps working after the person who built it has moved on. That means it belongs to you, it is written down, and somebody is watching it.

We connect, we don't replace

We build on the tools you have already chosen and paid for. You will never be told the fix is a new platform, and we don't earn anything from you switching.

You own what we build

The integrations, the credentials and the documentation are yours. Nothing runs on a ZeltaCode-only platform, so the whole thing goes with you if you work with someone else later.

It's monitored, not hoped for

APIs change without warning. Under Ongoing Support we watch what we've built and repair it — you shouldn't be the one who discovers it three weeks later from stale data.

Covered from launch and for as long as Ongoing Support is in place

FAQ

Common Questions

Straight answers about how we work, what things cost, and what happens after launch.

Still have a question?

Ask it in a free consultation — no pitch, just answers.

Book a Free Consultation

No. We connect the tools you already use and trust — we're not selling you a new platform.

That's what custom API development is for. If there's an API — and sometimes even if there isn't a documented one — we can usually still build the connection.

Yes. Legacy system integration and ERP integration services are two of the areas most agencies specifically avoid, and areas we specifically work in.

Zapier and Make are good tools for simple, low-stakes connections. Where we help is building integrations that hold up under real usage, handle edge cases properly, and don't quietly stop working when an upstream tool changes its API — with someone monitoring it, not just you finding out when something breaks.

That's covered under Ongoing Support. APIs change without warning — we monitor for that so you're not the one discovering it three weeks later.

Ready to Stop Doing This Manually?

Book a free consultation and find out what’s worth automating first.

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