# apt search jool
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  jool-dkms/stable 4.1.9-1 all
    kernel-based SIIT and NAT64 (IP/ICMP translation)

  jool-tools/stable 4.1.9-1 amd64
    userspace utilities for the Jool kernel modules

I suppose it is packaged, but dkms is still very much in the "why is does my router need a compiler installed" vibe.