100 DAYS AFTER

A survival story in one hundred days.

Lead a small band of survivors through a world ended by Grayfall — an engineered blight that came down with the dust. Every day you have a handful of actions, a ledger of hungry mouths, and a hundred ways to lose someone. What happens on Day 100 depends on what you built, learned, earned — and who you buried.

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Play

npm install
npm run dev        # → http://localhost:5199

Production build: npm run build then npm run preview.

Controls

• Everything is mouse-driven. Hover anything with a dotted underline for tooltips.
• Each day: spend limited actions (SCAVENGE / EXPLORE / HUNT / BUILD / TALK / TRADE / REPAIR / REST / TRAVEL), then press END DAY and read the night ledger.
• Click survivors for their full sheet: skills, traits, relationships, memories.
• The MAP tab previews each location's illustrated scene; the JOURNAL keeps your story.
• Encounters show honest odds for Fight / Hide / Run / Negotiate. Estimates. Not promises.

The shape of a run

Days	Phase	What happens
1–20	Early Survival	Scarcity, first strangers, learning the valley
21–50	Expansion	New faces, bigger camp, the wide world opens
51–80	Escalation	Raiders, herds of the Dust-Sick, hard choices
81–99	Endgame	Radio fragments resolve; escape plans form
100	Finale	Convoy, boats, the last raid… or something nobody told you about

Eight endings, including one hidden ending that requires three recovered radio parts, a seed vault, a running generator, and enough hope to be dangerous.

Runs are seeded and fully reproducible — same seed, same world. Share seeds.

Architecture

Clean separation of state, simulation, content and presentation:

src/
  engine/          pure logic, zero DOM
    types.ts       all shared types (GameState is plain serializable data)
    rng.ts         seeded mulberry32 + cursor (exact reproducibility)
    state.ts       new-game generation (survivors, map, weather, stores)
    sim-core.ts    caps, morale floor, defense rating, relationship math
    eventctx.ts    the mutation API events are written against (+ death & grief)
    sim.ts         actions, tactical encounters, night resolution, story beats
    ending.ts      ending selection + epilogue data
    save.ts        slots + autosave (localStorage), versioned envelopes
  content/         data-driven game content
    survivors.ts   names, occupations, traits, personalities, goals, weapons
    locations.ts   13 location templates (loot tables, risk, specials)
    buildings.ts   8 upgradeable structures
    enemies.ts     enemy archetypes
    world.ts       weather table, campaign phases, lore fragments
    events/
      people.ts    strangers, traders, internal conflict, callback chains
      world.ts     storms, creatures, factions, discoveries
      story.ts     scripted beats (Day 2→99), Day-100 finale, all endings
  ui/              presentation
    portraits.ts   procedural SVG character portraits with moods
    scene.ts       canvas parallax scenes, weather particles, camp rendering
    ui.ts          screens, HUD, modals, event/combat flow
  audio/audio.ts   synthesized wind/rain/thunder, adaptive music pads, SFX
scripts/
  headless.ts      auto-plays full campaigns across N seeds:
                   crash checks, determinism proof, balance histogram
  smoke.mjs        real-browser test: boot → play days → save → reload → load

Adding content never touches core systems: new events are entries in content/events/* (a title, conditions, choices with requirements, and outcome functions using the ctx helper API); new locations/buildings/enemies are plain data records.

Emergent storytelling systems

• Memory: every survivor logs what happened to them ("Skipped supper so others could eat").
• Grief: deaths ripple through relationships; close friends spiral, confront you, and remember on Day 99.
• Callback chains: rob the caravan and it returns; spare the stranger and he remembers; feed the family and a package appears at the fence weeks later.
• Feeding priority: food shortfalls feed the hungriest first — whoever's last in line develops opinions about leadership.
• Karma & hope quietly steer strangers' returns, tribute demands, and endings.

Testing

npm run sim          # 12 seeded campaigns, headless: crashes/determinism/balance
npm run sim -- --seeds=40
npm run smoke        # browser E2E through the real UI (needs the dev server)
npm run build        # typecheck + production bundle

Built as a vertical-slice-first project, expanded to the full 100-day campaign.