./scripts/run.sh

The run script will build both the front and backend, copy things into the right places, and then run the erlang server.

server/

Everything under server/ is code related to the backend of the project. The backend is an erlang app, so it's important to wrap gleam modules in if erlang { ... } so we don't mess up frontend builds.

app/

Everything in here is code related to the frontend of the project. For gleam source, it's important to wrap the entire module in if javascript { ... } so things build correctly.

shared/

This is where we put code that is shared between the front and backend. We shouldn't require any FFI here, and we should make sure any dependencies we pull in are compatible with both erlang and javascript.

How do I add dependencies?

For javascript dependencies everything is normal, just do npm i or npm i -D and you're good to go. For gleam dependencies things are bit more involved because we really have two gleam apps under one roof here.

The easiest way to add a new dependency is to copy either gleam.backend.toml or gleam.frontend.toml into gleam.toml (depending on whether you're adding a front or backend dependency) and then use gleam add ... like normal. Then copy the new entry in gleam.toml back to either gleam.backend.toml or gleam.frontend.toml respectively.

This is a bit of a hassle, I know, but I wanted all the source to live in a single app and this is the price we must pay for it.