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Full Manual: https://drive.google.com/file/d/1bZB9ZR7VG74hrAO13e2x6yNg0HgBOktY/view?usp=sharing

WE SUGGEST USING THIS MOD WITH THESE MODS:

Spud's Shop (Fork) - https://www.curseforge.com/minecraft/mc-mods/spuds-shop-fork
SDM Economy [Forge/Fabric] - https://www.curseforge.com/minecraft/mc-mods/sdm-economy

Stock Prices - Supply and Demand

A living economy. Prices that react to your world.

This is not a shop mod. It is the market underneath one. Stock Prices decides what every item SHOULD be worth, and that worth moves on its own as your world changes: as goods are mined or destroyed, as a player corners the market in a hidden vault, as money piles up or burns in a war. Players can manipulate the economy through hoarding, flooding, and supply disruption, and the price of a siege shows up on the shelves a few days later. It pairs with Spud's Shop to put those living prices on real stalls.

How the market works

Every Minecraft day the server recomputes a Standard Retail Price (SRP) for every obtainable item, from a single model. References calibrate on first launch, so day one prices equal your base prices and everything moves relative to that. Prices ease toward their target at one rate, so a sudden shock still lands within a day or two while ordinary drift is gradual, and rises and falls behave the same way.

The forces that move a price

- Supply. The more of an item that exists in the world, the cheaper it gets.
- Hoarding. Scarcity is about distribution, not just totals. The mod measures how concentrated an item is (its average per chunk) and treats a stockpile locked in one vault as if it is out of circulation. So if one player corners every ingot of iron, the price climbs even though there is more iron than ever, because almost none of it is actually on the market. This is the heart of the mod.
- Money supply. Every currency item in the world counts as money. Hoard or print currency and every price inflates; drain it and prices fall. This makes a treasury, or its loss in a war, something the whole market feels.
- Demand. The model carries a tunable demand factor for buying pressure (see the roadmap below).

The keybind: see the whole market

Press the bound key (set it in Controls, under Stock Prices) to open the Market Prices screen. Search any item as you type; every obtainable commodity shows its icon, name, and current value, with a 7-day trend arrow (green up, red down, a dash for no real change) and the percentage. Sort by name, by price, or by Movers to instantly see what war or hoarding is doing to the market. Spawn eggs, air, and technical blocks are kept out automatically, and the list is fully compatible with modded items.

Spud's Shop integration

With Spud's Shop (Fork) installed, open a stall you own and you will find an SRP checkbox at the right of the owner screen: a box that fills in when it is on, with a hover tooltip telling you its state. Toggle it on and that stall hands its pricing over to the market. The price updates the moment you toggle, and again every Minecraft day, with no need to touch it again. Wake up to find your potato stall has crashed because the market is flooded, or spiked because someone burned the world's supply.

Prices are written in smart bills. Instead of asking a customer for 1000 emeralds, the mod uses the largest coin that fits, so a price of 1000 becomes 10 diamonds, while small prices stay in emeralds. You define the coin ladder in config.

Currency, two ways

The currency denominations you configure do double duty. As bills, they shape what a stall charges (the fewest, largest coins). As money, every one of those items in the world is counted into the economy's money pool at its configured value. So the same emeralds and diamonds that pay for goods are also the money supply that inflates them. One list, both jobs.

How supply is measured

Minecraft keeps no record of what sits in unloaded chunks, so the mod builds its own. As chunks load and unload it quietly indexes their containers, and counts ender chests and online inventories too. Supply is the sum of every chunk it has seen, using the last known contents of ones that are currently unloaded. A chest in a dungeon you have never visited is invisible, exactly as it should be, and a hidden stockpile keeps propping a price up until someone disturbs it. Container scans are spread out over time, so joining a world never stalls on them, and prices are saved, so they survive a restart untouched.

Commodity model

- Synonyms merge. Two mods that both add garlic become one commodity at one price.
- Reversible storage groups with weights. An iron block counts as nine ingots, a nugget as a ninth, all one price.
- One-way processing stays separate. Ore, raw metal, and the finished ingot are different commodities, so a smelting bottleneck in a war shows up as cheap ore and expensive ingots.
- Manual include and exclude lists let you fix anything the auto-detector gets wrong.

Configuration

A full config file (config/stockprices-common.toml) tunes everything: how hard scarcity, hoarding, and money pull on prices, how sharply hoarding bites and at what concentration, how fast prices move, the floor and ceiling, default and per-item base prices, the commodity groups, the include and exclude lists, the currency ladder, the trend window, and a performance budget for the chunk scanner. There are also a few admin and test commands (/stockprices market, recompute, reload, and info) to open the market, force a recompute, reload commodities, and inspect exactly what the engine sees for the item in your hand.

Compatibility

Stock Prices runs on its own and needs no other mods. Spud's Shop (Fork) is an optional integration: install it to get the SRP checkbox and stall pricing. SDM's economy is an optional money backbone. Both are detected at runtime, so nothing breaks if they are absent.

Roadmap

- Live demand from purchases: feeding actual sales at shops into the demand factor, so buying pressure drives prices up directly.
- Reading SDM account balances into the money pool alongside physical currency.

Requirements

- Minecraft 1.21.1
- NeoForge
- Optional: Spud's Shop (Fork), an SDM economy

About

This mod is play-tested in multiplayer and actively maintained. It is still growing, so expect the odd rough edge and please report anything you find. Feature ideas and bug reports are hugely appreciated.

JUST COMMENT FOR BUG REPORTS

Let the market decide.

-Barunn