I tend to relate to conservative with "small government", and in that light Lua would be a conservative language, because it has a small core and doesn't try to do too much.
His conservative definition is seems to be "everything that is wrong with the world" or something.
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Also, this older rant reads to me as Yegge saying that this "conservative guy" was responsible for Google's success:
"I've been debating whether to say this, since it'll smack vaguely of obsequiousness, but I've realized that one of the Google seed engineers (exactly one) is almost singlehandedly responsible for the amazing quality of Google's engineering culture. And I mean both in the sense of having established it, and also in the sense of keeping the wheel spinning. I won't name the person, and for the record he almost certainly loathes me, for reasons that are my own damn fault. But I'd hire him in a heartbeat: more evidence, I think, that the Done, and Gets Things Smart folks aren't necessarily your friends. They're just people you're lucky enough to have worked with.
At first it's entirely non-obvious who's responsible for Google's culture of engineering discipline: the design docs, audited code reviews, early design reviews, readability reviews, resisting introduction of new languages, unit testing and code coverage, profiling and performance testing, etc. You know. The whole gamut of processes and tools that quality engineering organizations use to ensure that code is open, readable, documented, and generally non-shoddy work.
But if you keep an eye on the emails that go out to Google's engineering staff, over time a pattern emerges: there's one superheroic dude who's keeping us all in line."
(http://steve-yegge.blogspot.com.br/2008/06/done-and-gets-thi...)