GNU assembler alternatives

I am trying to build my system from scratch, since I really like the idea of atomicity of each program in unix-like approach, I would like to preserve it as much as possible in my build. Since GNU binutils, in a way, violates this principle, I would like to know if there is just GNU assembler, which wouldn't be dependant on binutils? If not, are there any minimal and performant alternatives to GNU assembler? I know of yasm, but in case there is a better one, I would like to know of it. Thank you in advance.