The Ubuntu image sunside/bionic-libuv is based on ubuntu:disco, contains curl and vim-tiny as well as a custom built version of libuv.

docker build -t sunside/bionic-libuv:1.32.0 -f Dockerfile.disco-libuv .

The Mono image sunside/bionic-mono is based on a nightly build of mono-runtime. Make sure the build.sh file lists the correct versions; you can check them on the Mono download page and the Ubuntu package repository at http://origin-download.mono-project.com/repo/ubuntu/dists/bionic/main/binary-amd64/Packages (or similar, depending on the current version).

docker build -t sunside/disco-mono:6.4.0.198 -f Dockerfile.mono .

The dotnet image sunside/dotnet contains the latest dotnet ("preview2") CLI version from dot.net.

docker build -t sunside/dotnet:3.1.100-2.2.402 -f Dockerfile.dotnet .
docker build -t sunside/dotnet:3.1.100 -f Dockerfile.dotnet-slim .