Many many developers all over the net respect NASM for what it is:
a widespread (thus netwide), portable (thus netwide!), very flexible
and mature assembler tool with support for many output formats (thus netwide!!).
Now we have good news for you: NASM is licensed under the "simplified"
(2-clause) BSD license.
This means its development is open to even wider society of programmers
wishing to improve their lovely assembler.