sbuild binary package in Ubuntu Focal riscv64

 The sbuild suite of programs (buildd and sbuild) are used to build
 binary packages from source packages. sbuild does the actual package
 building.
 .
 sbuild uses chroots to build packages, which act as virtual, minimal
 operating system installations dedicated to package building. This
 means that a number of environments may be used for building
 simultaneously on the same machines, for example stable, testing,
 unstable and experimental. When coupled with schroot to create
 snapshots of chroots, sbuild may be used to build many packages in
 parallel. A chroot environment allows packages to be built in a
 controlled, clean environment. sbuild installs only essential and
 build-essential packages, plus those in the package build
 dependencies.

Source package