Funding Marijn

I am Marijn Haverbeke. I created and maintain a number of software components that I distribute under permissive licenses.

CodeMirror ProseMirror Acorn Lezer

Building and maintaining software is skilled, specialized work. I prefer to allow the whole world to use my software, but I do need some kind of income.

Thus, I ask people and companies who use my software to make profit to fund the production of that software. This is a social expectation, not a legal requirement.

There are several ways in which you can help:

Monthly contribution of 100 €

You get a sponsor link on a project website, and a guarantee that I'll respond to your issues.

Monthly contribution of 250 €

Your logo on a project website, and a guarantee that I'll seriously look into your issues.

Monthly contribution of 500 €

Your logo a little bigger on a project website, and I'll spend up to five hours a month on your issues.

Monthly contribution of 1000 €

Your logo extra big on a project website, I'll spend up to ten hours a month on your issues, and will consider implementing new features or significant changes to address them.

Other monthly amount

Fund for an arbitrary amount per month.

Please use GitHub or Patreon for contributions below 25 € per month.

One-time contribution

Send me money once, when that's easier than a recurring contribution. You can pay by credit card here, or use Paypal.

Custom option

If you have questions or want a custom support contract, write me an email and we'll discuss it.


Payments made on this website (by credit card) go through Stripe. Your card information is never sent to my server.

The checkout process will ask you if you want an invoice.

If you have set up a recurring contribution, you can adjust or cancel it at any time by logging in with your email here:

Feel free to mention your company's contribution when reporting an issue that's important to you, since it's not always easy for me to see, at a glance, who works where.