How to build Jool kernel module on/for Turris 1.x?

Dear all, ahoj vsichni, is a NAT64/SIIT service, allowing you to build IPv6-only LANs with access to the IPv4 internet.

It has prebuilt packages for OpenWRT (, but the packages are not available in Turris repositories. As the software depends on the installed kernel (needs to be installed as a kernel module), I’d like to build the package from sources now. For that, however, there are lots of dependencies.

I didn’t find the kernel headers in the Turris repo (or didn’t search well), so I can’t figure out on where to start with the build.

How does anyone build kernel modules for Turris? Any hints?