Very fun! With such a simple set of upgrades, I still felt like I needed to make decisions about what I needed most after each day. The price increase from 1 to 3 might be a bit high--it's a bit silly to buy a 3 cost before the other 1-costs--but this also encouraged me to try each of the upgrades quickly. The sound effects really added a lot to the feel and mood of the game too! It took a bit of experimenting to figure out how it all worked, but I got there after a few (very short) runs :)
I think the fuel gauge needs to be more linear--it felt like it ran out very quickly on the final quarter, while the first quarter lasted a long time. If there's something affecting how quickly it runs out like threat level or something, that needs to be more obvious. I kept making a bit more progress than last run and wanted to see the end of the game, but kept suddenly running out of fuel despite focusing on managing that.
Great work! One of my favorites so far!