That's understandable, though one of the other commenters suggested the LGPL which might make for a good fit for your case. Here's a comparison with the other two if you're interested.

The AGPL is just the GPL with extra rules requiring sharing the code even if you expose it exclusively via a service.

AGPL is GPL + network services protection (preventing someone taking your code and spinning up a for-profit selling services without contribution back). If you don't care about people stealing your code, closing it, and selling services based on it, then there is no need to consider strict copyleft licenses.