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The metal-cpp wrapper released end of last year wraps the Metal 2 API, and by extension the basic NS foundation, in C++ code. From looking through the code, metal-cpp uses the objc/runtime.h header and uses objc_msgSend and sel_registerName to fetch pointers and call methods as if it were Objective-C code. This mostly works, however I've come across an issue where the renderCommandEncoderWithDescriptor: selector fails to load through sel_registerName. My application creates the default metal device, a command queue, a CAMetalLayer and I can present the drawable through a command buffer and all of it works. However, if I want to start actually rasterising any geometry, I need a MTLRenderCommandEncoder. To create one, I need to call renderCommandEncoderWithDescriptor: on a MTLCommandBuffer, which causes a segfault because the selector is 0x0 and the Objective-C runtime code tries to read from it. This short snippet is where the segfault occurs. Calling MTL::CommandBuffer::renderCommandEncoder will call the objc_msgSend with a 0x0 selector. auto buffer = queue->commandBuffer(); auto encoder = buffer->renderCommandEncoder(renderPass); MTLCommandBuffer buffer = [queue commandBuffer]; MTLRenderCommandEncoder encoder = [buffer renderCommmandEncoderWithDescriptor:renderPass]; And this would be the equivalent in raw Objective-C code, which does in fact work. I have uploaded a small test example to GitHub: https://github.com/spnda/metal-cpp-bug. This example uses GLFW to create the window and I use a small Objective-C++ file to modify the NSWindow and CAMetalLayer, as the metal-cpp wrapper curiously does not provide wrappers for these classes. I am personally on macOS Monterey 12.3 with a M1 iMac 24", it would be interesting to see if this is an issue with everybody, or just specific to my setup. Not being able to create a MTL::RenderCommandEncoder makes Apple's official Metal C++ wrappers absolutely useless for any rendering, and I would much appreciate any help to fix this issue.