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kotlinlang

I don't like that posting either, but I could imagine a conference ad being okay if there was a focus on Kotlin-- if the posting said something like "N sessions with a focus on Kotlin over M days!" then I think it would be sufficiently on-topic.
To me this message was similar to the "I'm using Dagger and it's not working: &lt;pastes Java code&gt;" type of questions we see occasionally.

I feel like an ad and somebody posting a SO question/problem are different things, even if they’re both off-topic

Fair enough, I was just sharing my perspective :slightly_smiling_face:  I think in this case the message might both be an ad _and_ off topic.