The little simulator that could. ksim is a simulator for Intel Skylake GPUs. It grew out of two tools I wrote a while back for capturing and decoding the output of the Intel open source drivers. Once you're capturing and decoding the command stream output by the driver it's a small step to start interpreting the stream. Initially, it was exciting to see it fetch vertices, but it has now snowballed into a fairly competent and efficient software rasterizer. As of March 22nd, ksim runs all major GL/Vulkan shader stages (vertex, hull, domain, geometry and fragment shaders) as well as compute shaders. It JIT compiles the Intel GPU ISA to AVX2 code on-the-fly using its own IR and compiler.