# 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 v0.7.0 of crustls. # Building with rustls First, [install Rust](https://rustup.rs/). Next, check out, build, and install the appropriate version of crustls: % cargo install cbindgen % git clone https://github.com/rustls/rustls-ffi -b v0.7.0 % cd crustls % make % make DESTDIR=${HOME}/crustls-built/ install Now configure and build curl with rustls: % git clone https://github.com/curl/curl % cd curl % ./buildconf % ./configure --with-rustls=${HOME}/crustls-built % make