$ checkbashisms ./rfc possible bashism in ./rfc line 74 (should be 'b = a'): if [ "$COMMIT" == "$new_commit" ]; then

$ checkbashisms install.sh possible bashism in install.sh line 3 ('function' is useless): function __install_rfc() { possible bashism in install.sh line 49 (unsafe echo with backslash): echo "\n# Added by 'rfc' installer\nexport PATH=\$PATH:\$HOME/bin" \

but above and beyond that, it requires GNU grep (uses GNU extension --excludes) to run the script itself