The developer himself says in the game that he was unable to finish it within the time constraints, which makes absolute sense. In any case game itself is essentially unfinished. I won't delve too deep into the game, especially because it's obvious even the dev himself isn't satisfied with his work. (No shame, I didn't even publish anything myself so I'm not one to talk)
The theme is taken very literally, with generated energy turning directly into matter at 1000 energy. Turning energy into matter serves 0 purpose, it provides no benefit to gained energy, it cannot be used to unlock upgrades (Unless they only start showing up after you collect more than 10 matter, after collecting that much I was more than finished with the game.) The energy collection process is not changed at all, and the effort required to make 1000 energy is not very difficult, and even easier with an auto clicker. With no change to the gameplay loop, it becomes incredibly stale after you've gained a single point of matter. The "upgrades" to energy collection which are simply "Auto-Generate Energy" and "Upgrade the Auto-Generator" aren't balanced at all, and after a few purchases become entirely pointless as their cost is more than a "Matterize" anyways.
I do think there is some bones here that are still usable, with a solid frame but not much else to go on, It's easy to imagine what could have been. An additional goal to work towards, some permanent upgrades to unlock, or really any other objective at all. Any release is better than nothing, so props to the dev for pushing out something, regardless of quality.