The sandbox begins with four founding traders: one fisher, baker, woodworker and weaver. The island always has exactly 100 gold coins. Arriving merchants bring no gold; they add production and become buyers of the other three goods. Prices update immediately. There is no timer, winning condition or score.

Try welcoming a fisher. Fish becomes cheaper because there is more of it, while the fisher adds demand for bread, timber and cloth. Those goods can become more expensive. Try a balanced boat: when production grows across all four goods at a steady trading pace, the same gold buys more goods.

A basket contains one fish, one loaf, one plank and one roll of cloth. Its starting price is 25 gold. Basket prices and gold purchasing power compare with those original four traders. Gold prices can be fractional; coins are treated as divisible.

This is an illustrative market-clearing model, not a forecast or a simulation of individual wallets. Each resident supplies their specialty and splits an equal spending budget among the other three goods. Total daily spending is 100 gold × trading pace. Each price equals that good’s share of spending divided by its available daily output. Sellers are assumed to clear the market.

Fixed gold alone does not guarantee deflation: prices also depend on output, preferences and how often coins circulate. Change the trading pace to explore that distinction. Undo and reset let you try another mix. The island supports up to 400 residents.