Running elixir LSP in docker

I would like to run the language server in a docker container, as it is the last piece of software in our project that is not running in docker. example

So far, I’m experimenting with this docker file:

FROM elixir:1.12.3-alpine

RUN wget https://github.com/elixir-tools/next-ls/releases/download/v0.22.2/next_ls_linux_arm64 -O next_ls
RUN chmod +x next_ls

CMD NEXTLS_SPITFIRE_ENABLED=1 ./next_ls --port 12000 && tail -f .elixir-tools/next-ls.log

It starts up correctly, but as soon as my editor tries to connect to it, it blows up:

$ docker run -ti -p 12000:12000 next-ls:latest
Starting on port 12000

init terminating in do_boot ({undef,[{elixir,start_cli,[],[]},{init,start_em,1,[]},{init,do_boot,3,[]}]})

Crash dump is being written to: erl_crash.dump...done

The first thing I’m noticing is that I get an undef in the do_boot, but I’m not sure what is it referring to.

I would like to debug it further, but I have no idea how to start.
Any suggestions where can I look further?