OCaml
Functional language with a powerful type system and optional mutability — used in compilers, proof assistants, and financial systems.
static
compiled
since 1996
functionaloopimperative
OCaml’s Hindley-Milner type system catches entire classes of bugs at compile time while its module system enables large-scale software architecture. It was the language of choice at Jane Street (financial trading) and inspired Rust’s ownership model. The Reason/ReScript dialects bring OCaml’s type system to JavaScript development.