Thanks - shahld_pk pointed me in the right direction. On inspection, it appears that a complete ‘debian’ folder isn’t included, rather a ‘package_tool’ script is included which outputs a ‘debian’ folder and then calls debuild to build the package.
Loosely the process is something like the following:
Follow the instructions here: https://github.com/dotnet/coreclr/blob/master/Documentation/building/linux-instructions.md
git clone https://github.com/dotnet/cli.git
mkdir ~/git/cli/$ #This bit doesn’t look right!
copy the appropriate contents from ~/git/coreclr/bin/Product/Linux.x64.Debug/ and ~/git/corefx/bin/Linux.x64.Debug/ into ~/git/cli/$
sudo apt-get install devscripts
~/git/cli/packaging/debian/package_tool/package_tool ~/git/cli /tmp/test/
The script then copies the binaries to /tmp/test/dotnet-0.201/, creates and populates /tmp/test/dotnet-0.201/debian/ and runs debuild to produce /tmp/test/dotnet_0.201-1_amd64.deb
I haven’t quite managed to put it all together yet, but I think that’s the idea. Having a directory called $ looks wrong, so I think I’ve misunderstood something there.