The following assumes a user named "builder" will be created to build packages.
- Create a Debian instance
- Update package database: apt-get update
- Install basic build system: apt-get install build-essential fakeroot devscripts
- Create mortal to build package and add to sudoers: adduser builder
- Add mortal to sudoers: usermod -aG sudo builder
- Allow mortal to sudo without password (optional): Create /etc/sudoers.d/builder-nopasswd containing: builder ALL=(ALL) NOPASSWD:ALL
- Become mortal: su -l builder
- Aquire the source in ~builder/packagename
- Acquire any dependencies: mk-build-deps debian/control && sudo apt-get install ./packagename-build-deps_*_all.deb
- Rebuild the unmodified binary package, unsigned: debuild -b -uc -us
- Install the package: sudo apt install ~builder/packagename.deb
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