Hosted or open-source Fortnox MCP server?

What you take on with your own MCP server

Running your own Fortnox MCP server from GitHub gives you full control over the code, but control and operations aren't the same thing. Before the server can talk to Fortnox, you need to register your own developer integration with Fortnox and get it approved — the same step Nordsynk itself went through for its hosted service.

After that, it's you — not the developer who wrote the code on GitHub — who's responsible for keeping the server up, secure, and current every day it's in use, whether it runs on your own VPS, a cloud function, or your laptop in a terminal window.

• !Register your own Fortnox developer integration and get it approved by Fortnox before you can even pull a client ID and secret to code against.
• !Host and monitor the server around the clock, whether it runs on a VPS, a cloud function, or your laptop in a terminal window.
• !Store and refresh Fortnox OAuth tokens securely yourself, including rotation when a token expires, gets revoked, or leaks by accident.
• !Update the code whenever the Fortnox API or the MCP spec changes — otherwise the integration quietly stops working until a customer asks why.
• !Build your own handling for multiple users and multiple Fortnox companies, since most open projects are written for a single login at a time.
• !Add your own gate for write operations, since most open-source servers don't ship a built-in approval step before a change reaches Fortnox.

What Nordsynk handles for you

Nordsynk flips the responsibility: you activate the integration in the Fortnox portal like any other Fortnox app, and Nordsynk runs, patches, and secures the server for every customer at once on Cloudflare Workers' global network.

It's the same principle that keeps you from self-hosting Fortnox's own accounting software — you just log in and use it. For an accounting firm switching between ten client companies before lunch, that means one connection per user instead of ten self-hosted servers to keep track of.

• ✓Activation happens directly in the Fortnox portal, like any other Fortnox app — no developer integration or approval process of your own required.
• ✓The server runs hosted on Cloudflare Workers and authenticates every session through Fortnox OAuth 2.0, without you ever touching a terminal.
• ✓Changes open a browser approval preview by default. Company-scoped auto-approve can be enabled; Fortnox permissions and Nordsynk access policies always apply.
• ✓Audit history logs every call with user, timestamp, and action, ready to show at an internal or external review.
• ✓Swedish workflows — supplier invoices with OCR and approval, SIE export, customer invoices — are built in from the start, not bolted on later.
• ✓Support is included in the price via hello@nordbeam.io, from a team that already knows Fortnox and Swedish bookkeeping inside out.

When open source is the right call

Open source is the right call when you're a developer who wants to experiment with the Fortnox API or build a fully custom pipeline inside a system that already has its own hosting and its own security work. In that case, the extra cost of Nordsynk is hard to justify — you're already paying for the infrastructure and already have the skills to run the OAuth flow.

It also fits a read-only side project: a developer building a Slack notification for new customer invoices needs neither write approvals nor multiple users, just a token and a scheduled job.

In both cases, free code is simply cheaper than a Nordsynk license, as long as you already have the time and the habit of running operations and security yourself.

Quick comparison

Frequently asked questions