one dataset · paper, tables, graph, wiki
simgrammar the grammar of simulation

parts

16 mechanics, as Stardew Valley does them

core · 5

progression & goals

Collection goals

Community Center bundles ask for sets of crops, forage, fish, and artisan goods; completed rooms repair town infrastructure and unlock areas, and the museum collects minerals and artifacts.

resources & production

Crop cultivation

Seasonal seeds need daily watering (rain or sprinklers substitute) and grow through stages over set day counts; most crops must be harvested before the season changes.

time & pacing

Daily action budget

An energy bar refills each morning, drains with tool use, and is restored by food; the clock forces bed by 2 a.m. or the player passes out and loses money.

social relations

Relationship values

Each villager has a friendship stock of 250 points per heart up to 10 hearts; it decays 2 points per day without talking, takes two gifts a week, multiplies birthday gifts by 8, and unlocks heart events.

environment & ecology

Seasons

Four 28-day seasons gate which crops grow, which fish and forage appear, and which festivals occur.

supporting · 11

agents & behavior

Agent skills

Farming, foraging, fishing, mining, and combat levels rise with practice and unlock recipes and professions.

biology & health

Animal husbandry

Barns and coops house animals that produce eggs, milk, and wool when fed and cared for; animals cannot be slaughtered.

space & construction

Building placement

agents & behavior

Daily schedules

Villagers follow routines that vary by weekday, season, and weather.

resources & production

Hand crafting

Recipes turn gathered materials into sprinklers, fences, machines, and bombs.

multiplayer & persistence

Modding API

SMAPI, the de facto mod loader, runs C# mods and content packs.

resources & production

Production chains

Kegs, preserves jars, and other machines convert crops and animal products into higher-value artisan goods over fixed processing times.

resources & production

Quality tiers

Crops and animal products come in normal, silver, gold, and iridium quality.

social relations

Romance and family

Twelve marriage candidates regardless of player gender; spouses help with chores, and couples can have children.

narrative & generation

Villager requests

A help-wanted board posts item, fishing, and slaying requests from townspeople.

environment & ecology

Weather

Rain waters crops and changes fish and villager routines.

watch

1 short with this record on screen
Short 2: Every part of Stardew Valley is older than it, opening frameplay · 0:40
rendered · short-02.mp4 · drawn from the dataset

short 2 0:40

Every part of Stardew Valley is older than it

transcript

Every part of Stardew Valley appears in an earlier game in our catalog.

Crops first appear in Hamurabi, a text game from 1968. A daily action budget first appears in Princess Maker 2, in 1993. Seasons and friendships with villagers first appear in Harvest Moon, in 1996, the game Stardew was built in response to.

That is the norm. Games released since 2010 draw 84 percent of their mechanics from parts that already existed by 2000.

Stardew sets its own numbers: 250 friendship points a heart, and two lost on each day you don't talk to someone.

also on the pages for

core loop

plan the day -> spend energy watering, harvesting, mining, or fishing -> sell crops and artisan goods -> buy seeds, tools, and buildings -> gift and talk to villagers -> complete Community Center bundles -> new areas and seasons open

design notes

Eric Barone built Stardew Valley alone over about five years in response to Harvest Moon, keeping its seasonal crop calendar and town relationships while leaving the long-term structure open-ended. Each day is bounded by an energy bar refilled each morning and a clock that forces sleep, so play is a daily allocation problem across farming, foraging, fishing, mining, and socializing. Friendship is a point stock (250 points per heart, 10 hearts for most villagers) that loses 2 points per day without conversation and accepts two gifts per week, with birthday gifts worth eight times as much. Community Center bundles make collection the main progression gate.

appears in

the paper, 2 sections · 5 chapters · 2 episodes · 1 short
paper

5. The structure of the design space

linked in this section of the paper

paper
paper

Appendix A. Game catalog

linked in this section of the paper

paper
catalog

The catalog

listed with its year, developer, subgenre, and number of mechanics

book
ch 2

Chapter 2. Six layers

linked from the text

book
ch 3

Chapter 3. Old parts

linked from the text

book
ch 4

Chapter 4. Families

linked from the text

book
ch 6

Chapter 6. Five ceilings

linked from the text

book
ch 10

Chapter 10. Bets

linked from the text

book
ep 2

Where the parts came from

on screen at 0:38 hamurabi in parts, 6:53 built from older parts

episode
ep 3

Families across genres

on screen at 3:18 odd couples

episode
short 2

Every part of Stardew Valley is older than it

0:40 · on screen in the short

short

relations

1 stored edges
influenced by

sources

3
Wikipedia contributors (2026). Stardew Valley. Wikipedia
Stardew Valley Wiki contributors (2026). Friendship. Stardew Valley Wiki
Stardew Valley Wiki contributors (2026). Bundles. Stardew Valley Wiki

provenance

runs in log/runs
2026-10-24
created2026-10-24-catalog-gccatalog
2026-10-24
reviewed2026-10-24-review-fixesmaintenance
2026-10-25
reviewed2026-10-25-contributor-readinessmaintenance