I have built some unofficial and experimental elm 0.19.1, elm-format 0.8.2 and elm-json 0.2.3 binaries for Raspberry Pi.
Installation
curl -L https://github.com/dmy/elm-raspberry-pi/releases/latest/download/elm.tar.gz | sudo tar zxC /usr/local/bin
The binaries have been tested only on a Raspberry 4 Model B with Raspbian GNU/Linux 10 (buster).
I believe that they should work on older Raspberry Pis and maybe other ARM 32 bits operating systems based on glibc, so please report any success or failure, here or in a GitHub issue.
Known issues
Because of a known ghc bug on ARMv7, SMP is disabled so elm will run only on a single core.
This is a good question, as I don’t use this myself, and my motivation to provide the binaries is also to evaluate the interest and the use cases.
A teacher on slack wanted to use Elm on Raspberry Pi with students for education, and I guess this is the main use case.
Apart from that, I don’t know either what are the other ones, but folks sometimes ask if some binaries are available and the Pi 4 is now a quite capable general-purpose computer, at a very low cost, so it can be used for whatever reason any computer is used.