It’s dynamically-typed and it doesn’t have real arrays. It can sometimes be frustratingly slow to do things that imperative languages do easily, but that’s the price of entry for functional languages. Luckily you can drop down into Rust or C if you need high performance.

Otherwise, it’s a great language. I’m consistently happy with the decisions that the Erlang and Elixir core teams make, and it’s my go-to language for web development.