./install.sh should get everything running on either macOS or Ubuntu.
For safely experimenting with new options, a docker file gives us a sandbox.
docker build -f ./test/Dockerfile . -t neovim-sandbox
docker run --rm -it -v ${PWD}:/nvim neovim-sandbox /bin/bash
cd /nvim
./install.sh
Note that something is stopping me running the install.sh as part of the docker build, so
this step always has to be manually executed after the sandbox opens.
If I try to keep a readme out here it'll almost certainly fall out of step. The config file is/will be commented at length