fakechroot 2.19-3.2 (amd64 binary) in ubuntu focal

 The fakechroot preloads a library which overrides libc functions, so
 it is possible to use root-specific tools without root privileges.
 .
 In fake chroot you can install i.e. Debian bootstrap, create developer's
 environment and build packages inside chroot'ed system using standard
 non-root user account.