Bdfl
Benevolent Dictator For Life
It originated in the Python community and is now generally used to describe the condition of an open-source leader who may find themselves saddled with more, and longer-term, expectations of selfless (bordering on martyrdom) leadership than they may want. — Venkatesh Rao, BDFx-ing
Wikipedia
Benevolent dictator for life (BDFL) is a title given to a small number of open-source software development leaders, typically project founders who retain the final say in disputes or arguments within the community. The phrase originated in 1995 with reference to Guido van Rossum, creator of the Python programming language.
I wanted to capture this snippet because it links to ESR's post. From my POV, I've only ever known it as BDFL.
BDFL should not be confused with the more common term for open-source leaders, "benevolent dictator", which was popularized by Eric S. Raymond's essay "Homesteading the Noosphere" (1999)