templates VS nix-beam-flakes

Unless you want to handwire something together or use another higher level function from some 3rd party library, your want to use this function. It is basically the entrypoint to a flake based nixos system configuration. See https://github.com/NixOS/templates/blob/master/simple-container/flake.nix for an example.

There are some templates on the official repository. https://github.com/NixOS/templates You can find others on github.

Don’t forget about the official templates. Built right into the CLI https://github.com/NixOS/templates

I am new to nix, and even newer when it comes to using flakes. I was trying out the following simple flake (based on this template), which just terminates with a segmentation fault whenever I use --impure flag (e.g. nix develop --impure)

You would probably want to use flakes. There is NixOS/templates repo with flake templates. Take a look at go-hello one.

You should consider adding this as a template to https://github.com/nixos/templates.

I left it vague because I didn't want to seem self-promotional. Unmerged documentation branch is the best starting place here: README, docs folder of that branch, example from develop. I daily drive it at work, and on a personal project for about 8 months. Doesn't do well for monorepos with disparate BEAM versions yet, but there are escape hatches and usage-as-library too. For the typical Phoenix project with a few extra system deps it's a pretty good onramp. perSystem.beamWorkspace.devShell.extraPackages is how you add arbitrary buildInputs like your VIPS stuff and .extraArgs for additional arguments to mkShell, such as your non-sensitive envvars. There's a page for future goals too. Publishing the rendered docs as a static site is in my TODOs, it's mostly glue left.