Builders only request actions. A protected engine decides what physically happens, and checks that water, energy, food and materials are conserved.
Time. One real second is one minute here. Building takes 0.5 person-hours per kilogram, with three people working 8 hours a day, one structure at a time. These labor rates are assumptions.
Water. A finite 100,000 L aquifer. Pumping costs m·g·H / efficiency (20 m head, 50%). Source
Solar. Area × 5 kWh/m²/day × 20% efficiency × 0.85 performance. 40 kWh battery. Source
Crops. Irrigation follows FAO-56 Penman–Monteith evapotranspiration. Harvest after 30 well-watered days. Yield is an uncalibrated proxy. Source
People. 15 L water, 2,100 kcal and 3.5 m² shelter per person per day, from humanitarian minimums. Source
Weather is fixed and fictional. Wellbeing scores are a simple model, not a measure of happiness.