Overall a very simple yet fun game.
The bullet crafting is neat idea and feels good once you figure out what the flavours do. However until you unlock any flavours, levelling mean little and your success heavily comes down to the order of flavours you unlock.
On my first run I nearly lost due to everything out-scaling my damage as it just so happened my last few flavours were all the damaging ones (fire-rate, piercing and finally bullet count). On my second run, I reversed the order and had a much easier time.
Otherwise its very good submission, good work.