A GC-free systems language isn't just for OS kernels. Rust's main use case was to replace C++ components in firefox. This wouldn't have been possible with a lan

A GC-free systems language isn't just for OS kernels. Rust's main use case was to replace C++ components in firefox. This wouldn't have been possible with a language that brings along its own GC, as Firefox already has a JS GC. Multiple garbage collectors in the same process are a quick way to madness, especially if you have reference cycles stretching across multiple GC heaps. This also comes up when writing Python extension modules, base libraries that are meant to be usable across languages, etc... This is part of why Rust is so successful -- it's the first real alternative for this space since C++ came along. For most application development, it's better to use a garbage collected language. But in the application space there is a much bigger choice of languages already available, Rust wouldn't have been a big deal over there.