That's definitely not the first game that would pop into my mind when thinking about Minetest (and I don't even think it's a great stand-alone game concept, it feels more like a minigame) but the author made a really nice job porting an endless runner videogame into Minetest. Collecting coins is rewarding, it can jump AND slide (the dead animation also works perfectly, congratulations for using the tools the game already gives you), and with the music defaulted to on it would have been even better.
If I have to find some critiques, putting it into a cave would have made more sense with the title, as the empty sky is somehow out of context. Also, I think that, after a while, the author just copy-pasted a piece of the map over and over, but (if I'm right) it's a jam and it's totally understandable.
P.S.: I know that saying the following isn't impartial as I'm the author, but consider to use arena_lib to turn it into a really nice minigame that people can put into their servers