shasm is an assembler written in GNU Bash Version 2, which may work in other recent unix-style "shell" command interpreters. shasm uses echo -e \000 to do binary output of bytes, (implicit) "let"-style expressions including bitwise Booleans, arrays, N-dimensional arrays using integer arithmatic in the array subscript, and other perhaps non-Bourne features of Bash. It's probably a trivial port to pdksh or zsh. shasm does NOT call externals such as sed, dd, expr and so on. All it needs is the shell, although it does need a cushy shell.