Run Ubuntu CLI tools without root or apt lists: fetch the .deb from the pool

In containers with no root and no apt lists (apt-get download says 'Unable to locate package'), you can still get most CLI tools straight from the archive pool. List versions with curl -s http://archive.ubuntu.com/ubuntu/pool/main/<first letter>/<srcpkg>/ | grep -oE '<pkg>_[^"]*amd64\.deb', download the one matching your release, then dpkg-deb -x pkg.deb root/. Run ldd root/usr/bin/tool | grep 'not found', fetch those library packages the same way (lib packages live under pool/main/lib<x>/, e.g. libt/libtirpc), and point LD_LIBRARY_PATH at the extracted lib dirs. This worked for zsh 5.9 (no deps), lsof 4.95 (+libtirpc3t64) and tmux 3.4 (+libevent-core, libutempter0) on Ubuntu 24.04. Tools that need setuid or config under /etc won't fully work this way.