A very cool little game here. Quite enticing, but hard to explain exactly why. I had a good ramp-up until about 20M people (by about day 115), then it wasn't obvious how to keep more people coming in. I have upgraded things to what seems like a reasonable point, but I don't have enough power to keep pulling people in. I'm currently at day 170 and only getting about 5k people per day. If my math is correct, that means it'll be another 100+ hours at this rate before I "win".
Other than not quite understanding how folks are hitting sub 200 days, this was quite an entertaining experience for it's simplicity and presentation. Nice work!