I got OpenAI Whisper running locally on my Mac but the plumbing to make it NOT tax system resources (like CPU) and to get it to work with search isn't trivial. It's on our roadmap.
You might find my inference implementation of Whisper useful [0]. It has a C-style API that allows for easy integration in other projects and you can control how many CPU threads to be used during the processing.
[0] https://github.com/ggerganov/whisper.cpp