I perceive "guidelines" or "rules" having a very different connotation compared to a "code of conduct."
See for, example, the SQLite team adopting the Rule of St. Benedict as their "Code of Conduct," getting criticized for it, and changing it to a "Code of Ethics" in accordance with the Rule about seeking accommodation with your adversaries.
Note also that Hipp pretty much just let any criticism for that wash over him and, from all public appearances, stayed cool and just kept working on his stuff while the loudmouths got bored and found other people to bother.
See for, example, the SQLite team adopting the Rule of St. Benedict as their "Code of Conduct," getting criticized for it, and changing it to a "Code of Ethics" in accordance with the Rule about seeking accommodation with your adversaries.