Has anyone summited Everest without a Sherpa?

I'm curious, has anyone ever successfully scaled Mount Everest without the assistance of a Sherpa guide? It's a daunting feat, given the treacherous terrain and harsh weather conditions that climbers face on the world's tallest peak. I'm wondering if any solo climbers or small groups have managed to make it to the summit without relying on the expertise and experience of a Sherpa to guide them through the most challenging sections of the climb. It would be fascinating to learn about any such accomplishments and the strategies and preparations that went into them.