I like how the look of the game is so chill (pun intended) but the gameplay is soo stressful. Very nicely drawn art, I didn't come across any bugs. Like Nobody_of_Teron, I also had a bit trouble reading the font, but I could just manage it. Maybe go for a more basic font next time.
If you want to continue on this game after the GameJam, I would suggest an easier beginning of the game, so you don't get frustrated right away. Like maybe you're trained on how to serve customers in a warm location, then you get promoted to colder and colder climate locations, so the coal hauling gets harder and harder...