# DLib {#dlib} [DLib](http://dlib.net/) is a modern, C++\-based toolkit which provides several machine learning algorithms. ## Compiling without AVX support {#compiling-without-avx-support} Especially older CPUs don't support [AVX](https://en.wikipedia.org/wiki/Advanced_Vector_Extensions) (Advanced Vector Extensions) instructions that are used by DLib to optimize their algorithms. On the affected hardware errors like `Illegal instruction` will occur. In those cases AVX support needs to be disabled: ```nix self: super: { dlib = super.dlib.override { avxSupport = false; }; } ```