The Gleam toolchain can be compiled with Cargo, Rust's build tool. The most recent stable version of Rust needs to be installed, as other versions may not be able to compile Gleam.
Clone the Gleam source code repository at the version you want.
git clone https://github.com/gleam-lang/gleam.git --branch v1.14.0
cd gleam
Compile and install Gleam.
cargo install --path cargo-bin --force --locked