The default on MacOS is `md5`, while Nix only has `md5sum` available.
Therefore, make it possible to override the variable via the environment
so that flake.nix can set the correct binary name.
This adds a flake.nix file that makes it possible to quickly create a
development environment.
You can download Nix here, for use on your Linux or macOS system:
https://nixos.org/download.html
After you have installed Nix, you can enter the development environment
as follows:
nix develop
This drops you into a bash shell, where you can install TinyGo simply
using the following command:
go install
That's all! Assuming you've set up your $PATH correctly, you can now use
the tinygo command as usual:
tinygo version
You can also do many other things from this environment. Building and
flashing should work as you're used to: it's not a VM or container so
there are no access restrictions.