This is a good and original game, congrats on making it in only 9 days!
A few recommendations if you want to improve on it.
1. Gameplay
I got stuck early on, because I had no idea that it was possible to scroll. The documentation starts with "the game can be played entirely with the mouse" so I stopped reading there but that was a mistake.
It would help a lot if you had some onscreen buttons for zoom in/out. Ideally with tooltip that share the Q/E keyboard shortcut.
The "add" block came up early, but at the beginning this block is not needed since final outputs are added as needed and the bank block wasn't there yet. Consider making sure the "add" block only shows up after the bank block.
2. User interface
- the shop would be a lot more readable if buttons and machines looked different.
- I was expecting the shop UI to go away if I click outside of the shop "window".
- when moving with the arrow keys, players expect the shift key to speed up the movement (this is especially important in this game since you quickly get a large map)
- scrolling with the mouse was unsatisfying (this was on Firefox) it proceeds by big steps that somehow aren't the size I want. It would be much nicer to have faster, finer-grained scrolling, plus on-screen buttons to zoom to exact useful sizes (one map square, 3x3 map squares, etc.)
- we quickly end up having to spend some time zoomed out, and then it's impossible to read the squares. It would be nice to have easily parseable visual effects to indicate "bank full" or "no square in range of square harvester"
- for a game with spread-out units like this, consider starcraft-style keybindings: press control-1 to control-9 while a unit (or more) is selected to save the selection. Press 1-9 to select that unit again. Press it a second time quickly after to move to that unit. This would make navigation much more pleasant.