True, but that's not why I use it. If it was, I would have moved to Cyclone, which has improved Cheney on the MTA by adding threading support, and has a library

True, but that's not why I use it. If it was, I would have moved to Cyclone, which has improved Cheney on the MTA by adding threading support, and has a library system that doesn't suck (with chicken, you have to generate import files for every module in order for the system to compile or interpret your code, even if the modules get compiled into a single file: it's like .h files in C, but they're autogenerated. I usually use a make script to build them), and a macro system that (afaik) isn't O(n) if you evaluate in the macro environment by default. But beyond the elegance of Chicken's internals, it's probably the most practical Scheme implementation for just getting stuff done fast. It has excellent C FFI, a good stdlib with solid POSIX bindings, an excellent package repository with all the libraries you might need, and it's very fast. It's not about the elegance, although it's there, it's about practicality: getting stuff done, efficiently, effectively, and now, not later.