It's not just how easy it is to embed, it's also really small in both code + runtime size. I've shipped it on systems with sub 8mb of total system memory(we use

It's not just how easy it is to embed, it's also really small in both code + runtime size. I've shipped it on systems with sub 8mb of total system memory(we used a preallocated 400kb block), until quickjs came along there really wasn't anything comparable. It was also much faster than anything else at the time and regularly beat v8 in the benchmarks I ran. Unity+Unreal are the public engines out there but there's plenty of in-house engines and tool chains you don't really hear about. I wouldn't be surprised if it's still deployed in quite a few contexts.