This maybe isn’t really that significant of an accomplishment generally speaking, but I’ve lost something like 30–50 9x9 games to this bot so it’s very satisfying for me personally to finally beat it. 
Finally won against Cosumi Lv. 0 at 9x9
Of course, in a normal game I would’ve still lost by a few points due to komi; there’s no komi when you play against it at Lv. 0 and you always play black. Still, it was a pretty arduous and challenging process for me to get here and I had to refine a lot of random parts of my technique over the course of my attempts, most recently opening and attacking.
I can tell that I still have a tendency to play a little too passively/defensively, especially for 9x9; in this game I seem to make blunders of that sort about every 10 moves or so. After what @gennan said to me in “What might be some profitable angles of play from this midgame-ish position in a 9x9 game?” I’ve been working on improving my attacking play and trying to probe the limits of what it’s possible to make work so I’m not as skittish about trying invasions (which I think it’s fair to say can be quite scary in 9x9 because a failed invasion typically spells an instant loss and there are many ways for it to go badly because of the close-in sides—but there are also a lot of surprising things that can work). I still have work to do in this regard of course but it seems like I’ve made progress.
Anyway, maybe I should go back to playing against humans now XD I feel a little less afraid of playing in a way that’s like cartoonishly embarassing after that win (I know it’s kind of silly to worry about that but it’s so hard to help). I honestly kind of want to try 19x19 because I really like that it has more of a mix of strategy and tactics (9x9 is closer to “pure tactics” I think it’s fair to say even if it does also have like “full-board go strategy in miniature” in a sense). I feel a little anxious about how long 19x19 games can take though 
it’s such a silly thing to worry about I guess, since if I play 3–5 9x9 games in a row, which is typical, it can end up taking as long as a 19x19 game.