OndrejMirtes, The list of PHPStan sponsors steadily grows, and I'm so grateful for that. Thanks to these companies I'm able to do what I love as my full-time job.
The rule of thumb should be: If you're boasting about using open-source software in your job listing, you should sponsor it.
You can find all the ways to sponsor PHPStan on the website: https://phpstan.org/sponsor