I want to echo Gleam [0] as a project to watch out for. It's still very early, but it's evolving quickly, and has a big focus on providing ergonomic tooling.
It's an ML inspired, statically typed language that compiles down to Erlang, and supports interop with the existing ecosystem. This means that you get access to ADTs, type inference, etc, while still being able to lean on OTP for your concurrency primitives. There's also examples of calling it from Elixir, so there's the option of falling back to statically typed Gleam for an especially gnarly piece of code, and calling it from your Elixir application [1]. I wouldn't necessarily recommend this for commercial apps yet, but Gleam today is about as usable as early-Elm was, in my opinion.
The project is also very welcoming to new contributors, and Louis (the language's creator) does a great job of curating a list of beginner friendly issues to tackle in the compiler. I've been spending my evenings learning Rust by adding onto the language, and it's been a ton of fun. If you want to help out, there's a fairly active IRC channel on Freenode, in #gleam-lang :)
It's an ML inspired, statically typed language that compiles down to Erlang, and supports interop with the existing ecosystem. This means that you get access to ADTs, type inference, etc, while still being able to lean on OTP for your concurrency primitives. There's also examples of calling it from Elixir, so there's the option of falling back to statically typed Gleam for an especially gnarly piece of code, and calling it from your Elixir application [1]. I wouldn't necessarily recommend this for commercial apps yet, but Gleam today is about as usable as early-Elm was, in my opinion.
The project is also very welcoming to new contributors, and Louis (the language's creator) does a great job of curating a list of beginner friendly issues to tackle in the compiler. I've been spending my evenings learning Rust by adding onto the language, and it's been a ton of fun. If you want to help out, there's a fairly active IRC channel on Freenode, in #gleam-lang :)
[0] https://gleam.run
[1] https://dev.to/contact-stack/mixing-gleam-elixir-3fe3