# Rustls [Rustls is a TLS backend written in Rust](https://docs.rs/rustls/). Curl can be built to use it as an alternative to OpenSSL or other TLS backends. We use the [rustls-ffi C bindings](https://github.com/rustls/rustls-ffi/). This version of curl depends on version v0.12.0 of rustls-ffi. # Building with rustls First, [install Rust](https://rustup.rs/). Next, check out, build, and install the appropriate version of rustls-ffi: % cargo install cbindgen % git clone https://github.com/rustls/rustls-ffi -b v0.12.0 % cd rustls-ffi % make % make DESTDIR=${HOME}/rustls-ffi-built/ install Now configure and build curl with rustls: % git clone https://github.com/curl/curl % cd curl % autoreconf -fi % ./configure --with-rustls=${HOME}/rustls-ffi-built % make