Imported from David-Li0406/meta-skill-evloving (skill-flow/data/skills-refined-agentskillos-36k/skillsmp/game-engineering-team/SKILL.md). Install upstream with npx skills add David-Li0406/meta-skill-evloving --skill game-engineering-team. Copyright stays with the author.

Game Engineering Team

A multidisciplinary council of AAA-caliber engineers dedicated to building production-quality game systems for Farming in Purria.

The Engineering Council

Core Game Engineers (6)

UI/UX Engineers (5)

Data & Infrastructure (5)

Quality & Craft (4)

Integration Specialists (4)

Part I: Core Engineering Principles

The Engineering Manifesto

┌─────────────────────────────────────────────────────────────────────────────┐
│                    FARMING IN PURRIA ENGINEERING PRINCIPLES                 │
├─────────────────────────────────────────────────────────────────────────────┤
│                                                                             │
│  1. PLAYER FIRST                                                            │
│     Every technical decision serves the player experience.                  │
│     60fps on mobile. Instant feedback. No jank.                            │
│                                                                             │
│  2. TYPE SAFETY END-TO-END                                                  │
│     From database to UI, types are the contract.                           │
│     If it compiles, it should work.                                        │
│                                                                             │
│  3. EXPLICIT OVER CLEVER                                                    │
│     Readable code beats clever code.                                       │
│     The next developer is you in 6 months.                                 │
│                                                                             │
│  4. SMALL, COMPOSABLE PIECES                                                │
│     Functions do one thing. Components render one thing.                   │
│     Composition over inheritance.                                          │
│                                                                             │
│  5. FAIL FAST, RECOVER GRACEFULLY                                           │
│     Validate inputs immediately. Handle errors at boundaries.              │
│     Players should never see stack traces.                                 │
│                                                                             │
│  6. MEASURE EVERYTHING                                                       │
│     If we can't measure it, we can't improve it.                           │
│     Telemetry is not optional.                                             │
│                                                                             │
│  7. OPTIMIZE LAST                                                            │
│     Make it work. Make it right. Make it fast.                             │
│     Profile before optimizing.                                             │
│                                                                             │
└─────────────────────────────────────────────────────────────────────────────┘

The Technical Stack

┌─────────────────────────────────────────────────────────────────────────────┐
│                              TECH STACK                                     │
├─────────────────────────────────────────────────────────────────────────────┤
│                                                                             │
│  FRONTEND                          BACKEND                                  │
│  ────────                          ───────                                  │
│  React 18+                         Hono                                     │
│  TanStack Router                   tRPC                                     │
│  Zustand                           Drizzle ORM                              │
│  Tailwind CSS                      SQLite/Turso                             │
│  shadcn/ui                         Bun runtime                              │
│  Framer Motion                     Zod validation                           │
│                                                                             │
│  TOOLING                           INFRASTRUCTURE                           │
│  ───────                           ──────────────                           │
│  TypeScript 5+                     Cloudflare Pages                         │
│  Biome (lint/format)               Cloudflare Workers                       │
│  Vitest                            GitHub Actions                           │
│  Playwright (E2E)                  PostHog analytics                        │
│                                                                             │
└─────────────────────────────────────────────────────────────────────────────┘

Part II: Game Programming Patterns

Pattern 1: Finite State Machines (FSM)

When to Use: Phase management, UI states, game mode transitions

// Type-safe FSM with explicit transitions
type GamePhase = 'morning' | 'action' | 'resolution' | 'night';

interface PhaseTransitions {
  morning: 'action';
  action: 'resolution';
  resolution: 'night';
  night: 'morning';
}

type NextPhase<T extends GamePhase> = PhaseTransitions[T];

class GamePhaseMachine {
  private phase: GamePhase = 'morning';
  
  transition(): void {
    const transitions: Record<GamePhase, GamePhase> = {
      morning: 'action',
      action: 'resolution',
      resolution: 'night',
      night: 'morning',
    };
    
    this.phase = transitions[this.phase];
    this.onPhaseEnter(this.phase);
  }
  
  private onPhaseEnter(phase: GamePhase): void {
    // Phase-specific initialization
  }
}

Pattern 2: Command Pattern (Undo/Redo)

When to Use: Bet placement, farm actions, any reversible operation

interface Command {
  execute(): void;
  undo(): void;
  description: string;
}

class PlaceBetCommand implements Command {
  constructor(
    private potId: string,
    private betType: BetType,
    private amount: number,
    private gameState: GameState
  ) {}
  
  execute(): void {
    this.gameState.placeBet(this.potId, this.betType, this.amount);
  }
  
  undo(): void {
    this.gameState.removeBet(this.potId);
    this.gameState.refundCoins(this.amount);
  }
  
  get description() {
    return `Bet ${this.amount} on ${this.potId}`;
  }
}

class CommandHistory {
  private history: Command[] = [];
  private pointer = -1;
  
  execute(command: Command): void {
    // Clear redo stack
    this.history = this.history.slice(0, this.pointer + 1);
    command.execute();
    this.history.push(command);
    this.pointer++;
  }
  
  undo(): void {
    if (this.pointer >= 0) {
      this.history[this.pointer].undo();
      this.pointer--;
    }
  }
  
  redo(): void {
    if (this.pointer < this.history.length - 1) {
      this.pointer++;
      this.history[this.pointer].execute();
    }
  }
}

Pattern 3: Observer Pattern (Event Bus)

When to Use: Cross-system communication, triggers, achievements

type GameEvent = 
  | { type: 'POT_THRESHOLD_REACHED'; potId: string; threshold: number }
  | { type: 'TROUBLE_SPAWNED'; hexId: string; troubleType: TroubleType }
  | { type: 'SIMULIN_LEVELED'; simulinId: string; newLevel: number }
  | { type: 'TRIGGER_EARNED'; trigger: TriggerType }
  | { type: 'DAY_COMPLETED'; dayNumber: number };

type EventHandler<T extends GameEvent['type']> = (
  event: Extract<GameEvent, { type: T }>
) => void;

class GameEventBus {
  private handlers = new Map<GameEvent['type'], Set<EventHandler<any>>>();
  
  on<T extends GameEvent['type']>(type: T, handler: EventHandler<T>): () => void {
    if (!this.handlers.has(type)) {
      this.handlers.set(type, new Set());
    }
    this.handlers.get(type)!.add(handler);
    
    // Return unsubscribe function
    return () => this.handlers.get(type)?.delete(handler);
  }
  
  emit(event: GameEvent): void {
    const handlers = this.handlers.get(event.type);
    if (handlers) {
      handlers.forEach(handler => handler(event));
    }
  }
}

// Usage
const events = new GameEventBus();

// Trigger system listens for pot events
events.on('POT_THRESHOLD_REACHED', ({ potId, threshold }) => {
  if (threshold === 100) {
    checkForPerfectReadTrigger();
  }
});

Pattern 4: Object Pool (Performance)

When to Use: Particles, projectiles, frequently created/destroyed objects

class ObjectPool<T> {
  private pool: T[] = [];
  private activeCount = 0;
  
  constructor(
    private factory: () => T,
    private reset: (obj: T) => void,
    initialSize = 10
  ) {
    for (let i = 0; i < initialSize; i++) {
      this.pool.push(factory());
    }
  }
  
  acquire(): T {
    if (this.activeCount >= this.pool.length) {
      this.pool.push(this.factory());
    }
    return this.pool[this.activeCount++];
  }
  
  release(obj: T): void {
    const index = this.pool.indexOf(obj);
    if (index !== -1 && index < this.activeCount) {
      this.reset(obj);
      // Swap with last active
      [this.pool[index], this.pool[this.activeCount - 1]] = 
        [this.pool[this.activeCount - 1], this.pool[index]];
      this.activeCount--;
    }
  }
  
  releaseAll(): void {
    for (let i = 0; i < this.activeCount; i++) {
      this.reset(this.pool[i]);
    }
    this.activeCount = 0;
  }
}

Pattern 5: Strategy Pattern (Interchangeable Algorithms)

When to Use: AI behaviors, scoring algorithms, difficulty modes

interface ScoringStrategy {
  calculateScore(results: DayResults): number;
  getName(): string;
}

class StandardScoring implements ScoringStrategy {
  calculateScore(results: DayResults): number {
    return results.potsWon * 100 + results.troubleCleared * 50;
  }
  getName() { return 'Standard'; }
}

class HarvestPhaseScoring implements ScoringStrategy {
  calculateScore(results: DayResults): number {
    // 3x multiplier during harvest phase
    return (results.potsWon * 100 + results.troubleCleared * 50) * 3;
  }
  getName() { return 'Harvest Bonus'; }
}

class GameScorer {
  constructor(private strategy: ScoringStrategy) {}
  
  setStrategy(strategy: ScoringStrategy): void {
    this.strategy = strategy;
  }
  
  score(results: DayResults): number {
    return this.strategy.calculateScore(results);
  }
}

Part III: Casino & Card Game Implementation

Random Number Generation

Critical: Use cryptographically secure, seedable RNG for fair play.

class SeededRNG {
  private seed: number;
  
  constructor(seed: number = Date.now()) {
    this.seed = seed;
  }
  
  // Mulberry32 - fast, good distribution
  next(): number {
    let t = this.seed += 0x6D2B79F5;
    t = Math.imul(t ^ t >>> 15, t | 1);
    t ^= t + Math.imul(t ^ t >>> 7, t | 61);
    return ((t ^ t >>> 14) >>> 0) / 4294967296;
  }
  
  // Range helpers
  nextInt(min: number, max: number): number {
    return Math.floor(this.next() * (max - min + 1)) + min;
  }
  
  nextFloat(min: number, max: number): number {
    return this.next() * (max - min) + min;
  }
  
  // Shuffle array (Fisher-Yates)
  shuffle<T>(array: T[]): T[] {
    const result = [...array];
    for (let i = result.length - 1; i > 0; i--) {
      const j = this.nextInt(0, i);
      [result[i], result[j]] = [result[j], result[i]];
    }
    return result;
  }
  
  // Weighted random selection
  weightedChoice<T>(items: T[], weights: number[]): T {
    const totalWeight = weights.reduce((a, b) => a + b, 0);
    let random = this.next() * totalWeight;
    
    for (let i = 0; i < items.length; i++) {
      random -= weights[i];
      if (random <= 0) return items[i];
    }
    return items[items.length - 1];
  }
}

// Usage with verifiable seed
const daySeed = hashString(`${seasonId}-day-${dayNumber}`);
const rng = new SeededRNG(daySeed);

Card Deck Management

interface Card {
  suit: 'hearts' | 'diamonds' | 'clubs' | 'spades';
  rank: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13;
}

class Deck {
  private cards: Card[] = [];
  private discardPile: Card[] = [];
  
  constructor(private rng: SeededRNG) {
    this.reset();
  }
  
  reset(): void {
    this.cards = [];
    this.discardPile = [];
    
    const suits: Card['suit'][] = ['hearts', 'diamonds', 'clubs', 'spades'];
    for (const suit of suits) {
      for (let rank = 1; rank <= 13; rank++) {
        this.cards.push({ suit, rank: rank as Card['rank'] });
      }
    }
    
    this.shuffle();
  }
  
  shuffle(): void {
    this.cards = this.rng.shuffle(this.cards);
  }
  
  draw(count = 1): Card[] {
    if (this.cards.length < count) {
      // Reshuffle discard pile into deck
      this.cards = [...this.cards, ...this.rng.shuffle(this.discardPile)];
      this.discardPile = [];
    }
    
    return this.cards.splice(0, count);
  }
  
  discard(cards: Card[]): void {
    this.discardPile.push(...cards);
  }
  
  get remaining(): number {
    return this.cards.length;
  }
  
  peek(count = 1): Card[] {
    return this.cards.slice(0, count);
  }
}

Poker Hand Evaluation

type HandRank = 
  | 'high-card'
  | 'pair'
  | 'two-pair'
  | 'three-of-a-kind'
  | 'straight'
  | 'flush'
  | 'full-house'
  | 'four-of-a-kind'
  | 'straight-flush'
  | 'royal-flush';

interface HandResult {
  rank: HandRank;
  value: number;        // For comparing same-rank hands
  cards: Card[];        // The 5 cards making the hand
  kickers: Card[];      // Remaining cards for tiebreakers
}

class PokerHandEvaluator {
  evaluate(cards: Card[]): HandResult {
    if (cards.length < 5) {
      throw new Error('Need at least 5 cards');
    }
    
    // If more than 5 cards, find best 5-card hand
    if (cards.length > 5) {
      return this.findBestHand(cards);
    }
    
    const sorted = [...cards].sort((a, b) => b.rank - a.rank);
    const isFlush = this.checkFlush(sorted);
    const straightRank = this.checkStraight(sorted);
    const groups = this.groupByRank(sorted);
    
    // Check for each hand type
    if (isFlush && straightRank === 14) {
      return { rank: 'royal-flush', value: 1000, cards: sorted, kickers: [] };
    }
    if (isFlush && straightRank > 0) {
      return { rank: 'straight-flush', value: 900 + straightRank, cards: sorted, kickers: [] };
    }
    if (groups[0].length === 4) {
      return this.buildResult('four-of-a-kind', 800, groups, sorted);
    }
    if (groups[0].length === 3 && groups[1]?.length === 2) {
      return this.buildResult('full-house', 700, groups, sorted);
    }
    if (isFlush) {
      return { rank: 'flush', value: 600 + this.highCardValue(sorted), cards: sorted, kickers: [] };
    }
    if (straightRank > 0) {
      return { rank: 'straight', value: 500 + straightRank, cards: sorted, kickers: [] };
    }
    if (groups[0].length === 3) {
      return this.buildResult('three-of-a-kind', 400, groups, sorted);
    }
    if (groups[0].length === 2 && groups[1]?.length === 2) {
      return this.buildResult('two-pair', 300, groups, sorted);
    }
    if (groups[0].length === 2) {
      return this.buildResult('pair', 200, groups, sorted);
    }
    
    return { 
      rank: 'high-card', 
      value: 100 + this.highCardValue(sorted), 
      cards: sorted, 
      kickers: sorted.slice(1) 
    };
  }
  
  private checkFlush(cards: Card[]): boolean {
    return cards.every(c => c.suit === cards[0].suit);
  }
  
  private checkStraight(cards: Card[]): number {
    const ranks = cards.map(c => c.rank).sort((a, b) => b - a);
    
    // Check for wheel (A-2-3-4-5)
    if (ranks[0] === 13 && ranks[1] === 5 && ranks[2] === 4 && 
        ranks[3] === 3 && ranks[4] === 2) {
      return 5; // Low straight
    }
    
    // Check regular straight
    for (let i = 0; i < ranks.length - 1; i++) {
      if (ranks[i] - ranks[i + 1] !== 1) return 0;
    }
    
    return ranks[0]; // High card of straight
  }
  
  private groupByRank(cards: Card[]): Card[][] {
    const groups = new Map<number, Card[]>();
    for (const card of cards) {
      if (!groups.has(card.rank)) groups.set(card.rank, []);
      groups.get(card.rank)!.push(card);
    }
    return Array.from(groups.values()).sort((a, b) => {
      if (a.length !== b.length) return b.length - a.length;
      return b[0].rank - a[0].rank;
    });
  }
  
  private highCardValue(cards: Card[]): number {
    return cards.reduce((acc, c, i) => acc + c.rank * Math.pow(15, 4 - i), 0);
  }
  
  private buildResult(
    rank: HandRank, 
    baseValue: number, 
    groups: Card[][], 
    sorted: Card[]
  ): HandResult {
    const mainCards = groups[0];
    const value = baseValue + mainCards[0].rank;
    return { rank, value, cards: sorted, kickers: groups.slice(1).flat() };
  }
  
  private findBestHand(cards: Card[]): HandResult {
    let best: HandResult | null = null;
    
    // Generate all 5-card combinations
    const combinations = this.combinations(cards, 5);
    
    for (const combo of combinations) {
      const result = this.evaluate(combo);
      if (!best || result.value > best.value) {
        best = result;
      }
    }
    
    return best!;
  }
  
  private *combinations<T>(arr: T[], k: number): Generator<T[]> {
    if (k === 0) { yield []; return; }
    if (arr.length < k) return;
    
    const [first, ...rest] = arr;
    for (const combo of this.combinations(rest, k - 1)) {
      yield [first, ...combo];
    }
    yield* this.combinations(rest, k);
  }
}

Pot/Betting System

type BetType = 'fold' | 'call' | 'raise' | 'all-in';

interface Pot {
  id: string;
  name: string;
  currentFill: number;     // 0-100
  thresholds: number[];    // [50, 80, 100]
  payoutMultipliers: Record<BetType, number[]>; // Per threshold
}

interface Bet {
  potId: string;
  betType: BetType;
  amount: number;
  placedAt: Date;
}

class BettingSystem {
  private bets: Bet[] = [];
  
  placeBet(potId: string, betType: BetType, amount: number): Bet {
    // Validate bet
    if (betType !== 'fold' && amount <= 0) {
      throw new Error('Bet amount must be positive');
    }
    
    // Check for existing bet on this pot
    const existing = this.bets.find(b => b.potId === potId);
    if (existing) {
      throw new Error('Already bet on this pot');
    }
    
    const bet: Bet = {
      potId,
      betType,
      amount: betType === 'fold' ? 0 : amount,
      placedAt: new Date(),
    };
    
    this.bets.push(bet);
    return bet;
  }
  
  resolveBets(pots: Pot[]): BetResult[] {
    const results: BetResult[] = [];
    
    for (const bet of this.bets) {
      const pot = pots.find(p => p.id === bet.potId);
      if (!pot) continue;
      
      const result = this.resolveSingleBet(bet, pot);
      results.push(result);
    }
    
    this.bets = [];
    return results;
  }
  
  private resolveSingleBet(bet: Bet, pot: Pot): BetResult {
    // Find highest threshold reached
    let thresholdIndex = -1;
    for (let i = pot.thresholds.length - 1; i >= 0; i--) {
      if (pot.currentFill >= pot.thresholds[i]) {
        thresholdIndex = i;
        break;
      }
    }
    
    // Fold always returns nothing
    if (bet.betType === 'fold') {
      return { bet, won: false, payout: 0, thresholdReached: thresholdIndex };
    }
    
    // No threshold reached = loss
    if (thresholdIndex < 0) {
      return { bet, won: false, payout: 0, thresholdReached: -1 };
    }
    
    // Calculate payout
    const multiplier = pot.payoutMultipliers[bet.betType][thresholdIndex];
    const payout = Math.floor(bet.amount * multiplier);
    
    return { 
      bet, 
      won: true, 
      payout, 
      thresholdReached: thresholdIndex,
      multiplier 
    };
  }
}

interface BetResult {
  bet: Bet;
  won: boolean;
  payout: number;
  thresholdReached: number;
  multiplier?: number;
}

Part IV: Reward & Progression Systems

Experience Curves

// Common XP curve formulas
const XP_CURVES = {
  // Linear: Simple, predictable
  linear: (level: number, base: number) => base * level,
  
  // Quadratic: Steeper growth
  quadratic: (level: number, base: number) => base * level * level,
  
  // Exponential: Slow start, rapid growth
  exponential: (level: number, base: number, rate: number) => 
    base * Math.pow(rate, level),
  
  // Polynomial: Customizable curve
  polynomial: (level: number, base: number, power: number) => 
    Math.floor(base * Math.pow(level, power)),
  
  // Fibonacci-like: Natural feeling progression
  fibonacci: (level: number, base: number) => {
    if (level <= 1) return base;
    let [a, b] = [base, base * 2];
    for (let i = 2; i < level; i++) {
      [a, b] = [b, a + b];
    }
    return b;
  },
};

class ProgressionSystem {
  constructor(
    private xpForLevel: (level: number) => number,
    private maxLevel: number = 100
  ) {}
  
  getLevel(totalXP: number): number {
    let level = 1;
    let xpNeeded = 0;
    
    while (level <= this.maxLevel) {
      xpNeeded += this.xpForLevel(level);
      if (totalXP < xpNeeded) break;
      level++;
    }
    
    return Math.min(level, this.maxLevel);
  }
  
  getProgress(totalXP: number): { level: number; current: number; needed: number; percent: number } {
    const level = this.getLevel(totalXP);
    const xpForCurrent = this.getTotalXPForLevel(level);
    const xpForNext = this.xpForLevel(level + 1);
    const current = totalXP - xpForCurrent;
    
    return {
      level,
      current,
      needed: xpForNext,
      percent: Math.floor((current / xpForNext) * 100),
    };
  }
  
  private getTotalXPForLevel(level: number): number {
    let total = 0;
    for (let i = 1; i < level; i++) {
      total += this.xpForLevel(i);
    }
    return total;
  }
}

// Simulin bonding uses gentle curve
const simulinProgression = new ProgressionSystem(
  (level) => XP_CURVES.polynomial(level, 100, 1.5),
  25 // Max bond level
);

Trigger & Combo System

interface DailyTrigger {
  type: TriggerType;
  earnedAt: Date;
  dayNumber: number;
  metadata?: Record<string, any>;
}

type TriggerType = 
  | 'first_bloom'
  | 'perfect_read'
  | 'trouble_slayer'
  | 'growth_spurt'
  | 'simulin_sync';

type ComboHandType = 
  | 'pair'
  | 'two_pair'
  | 'three_of_a_kind'
  | 'straight'
  | 'full_house'
  | 'flush'
  | 'four_of_a_kind'
  | 'straight_flush'
  | 'royal_flush';

class ComboEngine {
  private readonly HAND_VALUES: Record<ComboHandType, number> = {
    'pair': 2,
    'two_pair': 3,
    'three_of_a_kind': 5,
    'straight': 10,
    'full_house': 15,
    'flush': 20,
    'four_of_a_kind': 25,
    'straight_flush': 50,
    'royal_flush': 100,
  };
  
  evaluateWeek(triggers: DailyTrigger[]): ComboResult {
    // Group triggers by type
    const byType = new Map<TriggerType, number>();
    for (const trigger of triggers) {
      byType.set(trigger.type, (byType.get(trigger.type) || 0) + 1);
    }
    
    const counts = Array.from(byType.values()).sort((a, b) => b - a);
    const uniqueTypes = byType.size;
    const totalTriggers = triggers.length;
    
    // Evaluate hand (highest first)
    let handType: ComboHandType | null = null;
    
    // Royal Flush: All 5 types, perfect execution
    if (uniqueTypes === 5 && counts.every(c => c >= 1) && this.isPerfectSequence(triggers)) {
      handType = 'royal_flush';
    }
    // Straight Flush: 5 consecutive days, same category
    else if (this.isConsecutiveDays(triggers, 5) && this.hasCategoryMatch(triggers)) {
      handType = 'straight_flush';
    }
    // Four of a Kind
    else if (counts[0] >= 4) {
      handType = 'four_of_a_kind';
    }
    // Flush: 5 of same type
    else if (counts[0] >= 5) {
      handType = 'flush';
    }
    // Full House: 3 + 2
    else if (counts[0] >= 3 && counts[1] >= 2) {
      handType = 'full_house';
    }
    // Straight: 5 different in sequence
    else if (this.isConsecutiveDays(triggers, 5) && uniqueTypes >= 5) {
      handType = 'straight';
    }
    // Three of a Kind
    else if (counts[0] >= 3) {
      handType = 'three_of_a_kind';
    }
    // Two Pair
    else if (counts[0] >= 2 && counts[1] >= 2) {
      handType = 'two_pair';
    }
    // Pair
    else if (counts[0] >= 2) {
      handType = 'pair';
    }
    
    return {
      triggers,
      handType,
      multiplier: handType ? this.HAND_VALUES[handType] : 1,
      breakdown: Object.fromEntries(byType),
    };
  }
  
  private isConsecutiveDays(triggers: DailyTrigger[], required: number): boolean {
    const days = [...new Set(triggers.map(t => t.dayNumber))].sort((a, b) => a - b);
    let consecutive = 1;
    
    for (let i = 1; i < days.length; i++) {
      if (days[i] - days[i-1] === 1) {
        consecutive++;
        if (consecutive >= required) return true;
      } else {
        consecutive = 1;
      }
    }
    
    return consecutive >= required;
  }
  
  private hasCategoryMatch(triggers: DailyTrigger[]): boolean {
    // Define categories
    const categories: Record<string, TriggerType[]> = {
      betting: ['first_bloom', 'perfect_read'],
      farming: ['growth_spurt', 'trouble_slayer'],
      companion: ['simulin_sync'],
    };
    
    // Check if all triggers are from same category
    for (const types of Object.values(categories)) {
      if (triggers.every(t => types.includes(t.type))) {
        return true;
      }
    }
    return false;
  }
  
  private isPerfectSequence(triggers: DailyTrigger[]): boolean {
    // Perfect sequence: all 5 trigger types in optimal order
    const idealOrder: TriggerType[] = [
      'first_bloom', 'growth_spurt', 'trouble_slayer', 'perfect_read', 'simulin_sync'
    ];
    
    const byDay = new Map<number, TriggerType>();
    for (const t of triggers) {
      if (!byDay.has(t.dayNumber)) {
        byDay.set(t.dayNumber, t.type);
      }
    }
    
    const sequence = Array.from(byDay.entries())
      .sort(([a], [b]) => a - b)
      .map(([_, type]) => type);
    
    return sequence.length === 5 && 
           sequence.every((type, i) => type === idealOrder[i]);
  }
}

interface ComboResult {
  triggers: DailyTrigger[];
  handType: ComboHandType | null;
  multiplier: number;
  breakdown: Record<TriggerType, number>;
}

Part V: UI Engineering Patterns

Component Architecture

// Compound Component Pattern for complex UI
interface SlotMachineContext {
  spinning: boolean;
  result: SlotResult | null;
  spin: () => void;
}

const SlotMachineContext = createContext<SlotMachineContext | null>(null);

function SlotMachine({ children }: { children: React.ReactNode }) {
  const [spinning, setSpinning] = useState(false);
  const [result, setResult] = useState<SlotResult | null>(null);
  
  const spin = useCallback(async () => {
    setSpinning(true);
    const newResult = await api.spin();
    setResult(newResult);
    setSpinning(false);
  }, []);
  
  return (
    <SlotMachineContext.Provider value={{ spinning, result, spin }}>
      <div className="slot-machine">{children}</div>
    </SlotMachineContext.Provider>
  );
}

// Sub-components
SlotMachine.Reel = function Reel({ index }: { index: number }) {
  const ctx = useContext(SlotMachineContext);
  // ...render reel
};

SlotMachine.SpinButton = function SpinButton() {
  const ctx = useContext(SlotMachineContext);
  return (
    <button onClick={ctx?.spin} disabled={ctx?.spinning}>
      {ctx?.spinning ? 'Spinning...' : 'SPIN'}
    </button>
  );
};

// Usage
<SlotMachine>
  <SlotMachine.Reel index={0} />
  <SlotMachine.Reel index={1} />
  <SlotMachine.Reel index={2} />
  <SlotMachine.SpinButton />
</SlotMachine>

Animation Patterns

import { motion, AnimatePresence, useSpring, useTransform } from 'framer-motion';

// Juice: Satisfying feedback animations
const JUICE_VARIANTS = {
  // Pop in
  pop: {
    initial: { scale: 0, opacity: 0 },
    animate: { scale: 1, opacity: 1 },
    exit: { scale: 0, opacity: 0 },
    transition: { type: 'spring', stiffness: 500, damping: 30 },
  },
  
  // Bounce
  bounce: {
    animate: { 
      y: [0, -10, 0],
      transition: { duration: 0.3, times: [0, 0.5, 1] }
    },
  },
  
  // Shake (for errors/wrong)
  shake: {
    animate: { 
      x: [0, -10, 10, -10, 10, 0],
      transition: { duration: 0.4 }
    },
  },
  
  // Pulse (for attention)
  pulse: {
    animate: { 
      scale: [1, 1.05, 1],
      transition: { duration: 0.3, repeat: 2 }
    },
  },
};

// Number counter animation
function AnimatedNumber({ value }: { value: number }) {
  const spring = useSpring(value, { stiffness: 100, damping: 30 });
  const display = useTransform(spring, (v) => Math.floor(v).toLocaleString());
  
  useEffect(() => {
    spring.set(value);
  }, [value, spring]);
  
  return <motion.span>{display}</motion.span>;
}

// Stagger children animation
function StaggeredList({ items }: { items: React.ReactNode[] }) {
  return (
    <motion.ul
      initial="hidden"
      animate="visible"
      variants={{
        visible: { transition: { staggerChildren: 0.1 } },
      }}
    >
      {items.map((item, i) => (
        <motion.li
          key={i}
          variants={{
            hidden: { opacity: 0, x: -20 },
            visible: { opacity: 1, x: 0 },
          }}
        >
          {item}
        </motion.li>
      ))}
    </motion.ul>
  );
}

Responsive Game UI

// Hook for responsive game scaling
function useGameScale() {
  const [scale, setScale] = useState(1);
  const containerRef = useRef<HTMLDivElement>(null);
  
  useEffect(() => {
    const updateScale = () => {
      if (!containerRef.current) return;
      
      const container = containerRef.current;
      const parent = container.parentElement;
      if (!parent) return;
      
      const DESIGN_WIDTH = 390;  // iPhone 12/13 width
      const DESIGN_HEIGHT = 844;
      
      const scaleX = parent.clientWidth / DESIGN_WIDTH;
      const scaleY = parent.clientHeight / DESIGN_HEIGHT;
      
      // Use minimum to ensure everything fits
      setScale(Math.min(scaleX, scaleY, 1.5)); // Cap at 1.5x
    };
    
    updateScale();
    window.addEventListener('resize', updateScale);
    return () => window.removeEventListener('resize', updateScale);
  }, []);
  
  return { scale, containerRef };
}

// Usage
function GameScreen() {
  const { scale, containerRef } = useGameScale();
  
  return (
    <div className="game-container" ref={containerRef}>
      <div 
        className="game-content"
        style={{ transform: `scale(${scale})`, transformOrigin: 'top center' }}
      >
        {/* Fixed-size game UI designed for 390x844 */}
      </div>
    </div>
  );
}

Part VI: Data Architecture

Schema Design Principles

// Use branded types for IDs
type SeasonId = string & { readonly brand: unique symbol };
type SimulinId = string & { readonly brand: unique symbol };
type UserId = string & { readonly brand: unique symbol };

function createSeasonId(): SeasonId {
  return `season_${crypto.randomUUID()}` as SeasonId;
}

// Drizzle schema with relations
import { sqliteTable, text, integer, real } from 'drizzle-orm/sqlite-core';
import { relations } from 'drizzle-orm';

export const users = sqliteTable('users', {
  id: text('id').primaryKey(),
  email: text('email').notNull().unique(),
  createdAt: integer('created_at', { mode: 'timestamp' }).notNull(),
});

export const seasons = sqliteTable('seasons', {
  id: text('id').primaryKey(),
  userId: text('user_id').notNull().references(() => users.id),
  seasonNumber: integer('season_number').notNull(),
  currentDay: integer('current_day').notNull().default(1),
  phase: text('phase', { enum: ['planting', 'growth', 'harvest'] }).notNull(),
  jackpotContribution: real('jackpot_contribution').notNull().default(0),
  startedAt: integer('started_at', { mode: 'timestamp' }).notNull(),
  completedAt: integer('completed_at', { mode: 'timestamp' }),
});

export const seasonsRelations = relations(seasons, ({ one, many }) => ({
  user: one(users, {
    fields: [seasons.userId],
    references: [users.id],
  }),
  triggers: many(dailyTriggers),
  simulins: many(simulins),
}));

export const dailyTriggers = sqliteTable('daily_triggers', {
  id: text('id').primaryKey(),
  seasonId: text('season_id').notNull().references(() => seasons.id),
  dayNumber: integer('day_number').notNull(),
  triggerType: text('trigger_type').notNull(),
  earnedAt: integer('earned_at', { mode: 'timestamp' }).notNull(),
  metadata: text('metadata', { mode: 'json' }),
});

export const simulins = sqliteTable('simulins', {
  id: text('id').primaryKey(),
  userId: text('user_id').notNull().references(() => users.id),
  seasonId: text('season_id').references(() => seasons.id),
  name: text('name').notNull(),
  stage: text('stage', { enum: ['sproutling', 'cultivar', 'bloomform', 'legendary'] }).notNull(),
  path: text('path', { enum: ['tender', 'watcher', 'lucky'] }),
  bondLevel: integer('bond_level').notNull().default(1),
  bondXP: integer('bond_xp').notNull().default(0),
  personality: text('personality', { mode: 'json' }).notNull(),
  createdAt: integer('created_at', { mode: 'timestamp' }).notNull(),
});

Logging & Telemetry

interface GameEvent {
  type: string;
  timestamp: Date;
  sessionId: string;
  userId?: string;
  properties: Record<string, any>;
}

class Telemetry {
  private queue: GameEvent[] = [];
  private flushInterval: Timer;
  
  constructor(
    private endpoint: string,
    private batchSize = 10,
    private flushIntervalMs = 5000
  ) {
    this.flushInterval = setInterval(() => this.flush(), flushIntervalMs);
  }
  
  track(type: string, properties: Record<string, any> = {}): void {
    const event: GameEvent = {
      type,
      timestamp: new Date(),
      sessionId: this.getSessionId(),
      userId: this.getUserId(),
      properties: {
        ...properties,
        // Auto-add context
        url: typeof window !== 'undefined' ? window.location.href : undefined,
        userAgent: typeof navigator !== 'undefined' ? navigator.userAgent : undefined,
      },
    };
    
    this.queue.push(event);
    
    if (this.queue.length >= this.batchSize) {
      this.flush();
    }
  }
  
  private async flush(): Promise<void> {
    if (this.queue.length === 0) return;
    
    const batch = this.queue.splice(0, this.batchSize);
    
    try {
      await fetch(this.endpoint, {
        method: 'POST',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify({ events: batch }),
      });
    } catch (error) {
      // Re-queue failed events (with limit)
      if (this.queue.length < 100) {
        this.queue.unshift(...batch);
      }
      console.error('Telemetry flush failed:', error);
    }
  }
  
  private getSessionId(): string {
    // Session ID from storage or generate new
    let sessionId = sessionStorage.getItem('fip_session_id');
    if (!sessionId) {
      sessionId = crypto.randomUUID();
      sessionStorage.setItem('fip_session_id', sessionId);
    }
    return sessionId;
  }
  
  private getUserId(): string | undefined {
    // Get from auth state
    return undefined; // Implement based on auth system
  }
  
  destroy(): void {
    clearInterval(this.flushInterval);
    this.flush();
  }
}

// Standard events
const telemetry = new Telemetry('/api/telemetry');

// Usage
telemetry.track('day_started', { dayNumber: 5, phase: 'growth' });
telemetry.track('bet_placed', { potId: 'water', betType: 'raise', amount: 100 });
telemetry.track('trigger_earned', { triggerType: 'perfect_read' });
telemetry.track('session_ended', { duration: 1234, daysPlayed: 3 });

Security Patterns

// Input validation with Zod
import { z } from 'zod';

const PlaceBetSchema = z.object({
  potId: z.enum(['water', 'sun', 'pest', 'growth']),
  betType: z.enum(['fold', 'call', 'raise', 'all-in']),
  amount: z.number().int().min(0).max(10000),
});

// Rate limiting
class RateLimiter {
  private requests: Map<string, number[]> = new Map();
  
  constructor(
    private windowMs: number,
    private maxRequests: number
  ) {}
  
  isAllowed(key: string): boolean {
    const now = Date.now();
    const windowStart = now - this.windowMs;
    
    // Get and filter old requests
    const timestamps = (this.requests.get(key) || [])
      .filter(t => t > windowStart);
    
    if (timestamps.length >= this.maxRequests) {
      return false;
    }
    
    timestamps.push(now);
    this.requests.set(key, timestamps);
    return true;
  }
}

// Server-side validation wrapper
function validateRequest<T>(
  schema: z.ZodSchema<T>,
  data: unknown,
  context: { userId: string; ip: string }
): T {
  // Rate limit check
  const rateLimiter = new RateLimiter(60000, 100); // 100 req/min
  if (!rateLimiter.isAllowed(context.userId)) {
    throw new Error('Rate limit exceeded');
  }
  
  // Schema validation
  const result = schema.safeParse(data);
  if (!result.success) {
    console.warn('Validation failed', { 
      userId: context.userId, 
      errors: result.error.errors 
    });
    throw new Error('Invalid request data');
  }
  
  return result.data;
}

// Anti-cheat: Server-authoritative game state
class GameStateValidator {
  validateDayAdvance(
    currentState: GameState,
    proposedState: GameState
  ): boolean {
    // Server recalculates expected state
    const expectedState = this.calculateNextState(currentState);
    
    // Compare critical values
    if (proposedState.coins > expectedState.maxPossibleCoins) {
      this.flagSuspicious('coin_manipulation', currentState.userId);
      return false;
    }
    
    if (proposedState.dayNumber !== expectedState.dayNumber) {
      this.flagSuspicious('day_skip', currentState.userId);
      return false;
    }
    
    return true;
  }
  
  private calculateNextState(current: GameState): ExpectedState {
    // Server-side calculation of valid state ranges
    return {} as ExpectedState;
  }
  
  private flagSuspicious(type: string, userId: string): void {
    // Log for review
    console.warn('Suspicious activity', { type, userId });
  }
}

Part VII: Tutorial System Design

Progressive Disclosure Pattern

interface TutorialStep {
  id: string;
  trigger: TutorialTrigger;
  content: TutorialContent;
  completion: CompletionCondition;
  next?: string;
}

type TutorialTrigger = 
  | { type: 'first_visit'; screen: string }
  | { type: 'action'; action: string }
  | { type: 'state'; condition: (state: GameState) => boolean }
  | { type: 'time'; delayMs: number };

interface TutorialContent {
  title: string;
  body: string;
  highlight?: string;  // CSS selector to highlight
  position?: 'top' | 'bottom' | 'left' | 'right' | 'center';
  character?: 'simulin' | 'npc';
  allowSkip?: boolean;
}

type CompletionCondition = 
  | { type: 'click'; target: string }
  | { type: 'action'; action: string }
  | { type: 'dismiss' }
  | { type: 'state'; condition: (state: GameState) => boolean };

const TUTORIAL_FLOW: TutorialStep[] = [
  {
    id: 'welcome',
    trigger: { type: 'first_visit', screen: 'farm' },
    content: {
      title: 'Welcome to Purria!',
      body: 'Your adventure in tulip farming begins here.',
      character: 'simulin',
      position: 'center',
    },
    completion: { type: 'dismiss' },
    next: 'intro_hex',
  },
  {
    id: 'intro_hex',
    trigger: { type: 'action', action: 'tutorial_continue' },
    content: {
      title: 'Your Farm',
      body: 'Each hex is a plot for growing tulips. Tap one to plant!',
      highlight: '.hex-grid',
      position: 'bottom',
    },
    completion: { type: 'action', action: 'hex_tap' },
    next: 'intro_pots',
  },
  {
    id: 'intro_pots',
    trigger: { type: 'action', action: 'plant_tulip' },
    content: {
      title: 'The Meta-Pots',
      body: 'These four pots fill based on daily events. Place bets on which will hit their threshold!',
      highlight: '.pot-display',
      position: 'top',
    },
    completion: { type: 'click', target: '.pot-display' },
    next: 'first_bet',
  },
  // ... more steps
];

class TutorialManager {
  private completedSteps: Set<string> = new Set();
  private currentStep: TutorialStep | null = null;
  
  constructor(
    private steps: TutorialStep[],
    private onShow: (step: TutorialStep) => void,
    private onHide: () => void
  ) {
    this.loadProgress();
  }
  
  checkTriggers(context: { screen: string; action?: string; state: GameState }): void {
    for (const step of this.steps) {
      if (this.completedSteps.has(step.id)) continue;
      if (this.currentStep?.id === step.id) continue;
      
      if (this.matchesTrigger(step.trigger, context)) {
        this.showStep(step);
        break;
      }
    }
  }
  
  private matchesTrigger(trigger: TutorialTrigger, context: any): boolean {
    switch (trigger.type) {
      case 'first_visit':
        return context.screen === trigger.screen && 
               !this.hasVisited(trigger.screen);
      case 'action':
        return context.action === trigger.action;
      case 'state':
        return trigger.condition(context.state);
      default:
        return false;
    }
  }
  
  private showStep(step: TutorialStep): void {
    this.currentStep = step;
    this.onShow(step);
  }
  
  completeCurrentStep(): void {
    if (!this.currentStep) return;
    
    this.completedSteps.add(this.currentStep.id);
    this.saveProgress();
    
    const nextId = this.currentStep.next;
    this.currentStep = null;
    this.onHide();
    
    if (nextId) {
      const nextStep = this.steps.find(s => s.id === nextId);
      if (nextStep && nextStep.trigger.type === 'action') {
        // Auto-show chained steps
        this.showStep(nextStep);
      }
    }
  }
  
  private loadProgress(): void {
    const saved = localStorage.getItem('tutorial_progress');
    if (saved) {
      this.completedSteps = new Set(JSON.parse(saved));
    }
  }
  
  private saveProgress(): void {
    localStorage.setItem(
      'tutorial_progress', 
      JSON.stringify([...this.completedSteps])
    );
  }
  
  private hasVisited(screen: string): boolean {
    return localStorage.getItem(`visited_${screen}`) === 'true';
  }
  
  reset(): void {
    this.completedSteps.clear();
    localStorage.removeItem('tutorial_progress');
  }
}

Contextual Help System

interface HelpTopic {
  id: string;
  title: string;
  summary: string;
  content: string;
  relatedTopics?: string[];
  triggers?: string[];  // UI elements that show this help
}

const HELP_TOPICS: HelpTopic[] = [
  {
    id: 'betting',
    title: 'How Betting Works',
    summary: 'Place bets on which pots will fill',
    content: `
      Each day, the four Meta-Pots fill based on events on your farm.
      
      **Bet Types:**
      - **Fold**: Skip this pot (safe, no reward)
      - **Call**: Small bet, small reward
      - **Raise**: Medium bet, medium reward  
      - **All-In**: Big bet, big reward (or loss!)
      
      **Thresholds:**
      Pots have thresholds at 50%, 80%, and 100%. Higher thresholds = higher payouts.
    `,
    relatedTopics: ['pots', 'triggers', 'combos'],
    triggers: ['.bet-button', '.pot-display'],
  },
  // ... more topics
];

function HelpButton({ topicId }: { topicId: string }) {
  const [open, setOpen] = useState(false);
  const topic = HELP_TOPICS.find(t => t.id === topicId);
  
  if (!topic) return null;
  
  return (
    <>
      <button 
        onClick={() => setOpen(true)}
        className="help-button"
        aria-label={`Help: ${topic.title}`}
      >
        ?
      </button>
      
      <Dialog open={open} onClose={() => setOpen(false)}>
        <Dialog.Title>{topic.title}</Dialog.Title>
        <Dialog.Content>
          <Markdown>{topic.content}</Markdown>
          
          {topic.relatedTopics && (
            <div className="related-topics">
              <h4>Related:</h4>
              {topic.relatedTopics.map(id => (
                <HelpLink key={id} topicId={id} />
              ))}
            </div>
          )}
        </Dialog.Content>
      </Dialog>
    </>
  );
}

Part VIII: Quality Assurance

Testing Strategy

// Unit test example (Vitest)
import { describe, it, expect } from 'vitest';
import { ComboEngine } from './combo-engine';

describe('ComboEngine', () => {
  const engine = new ComboEngine();
  
  describe('evaluateWeek', () => {
    it('detects pair with 2 matching triggers', () => {
      const triggers = [
        { type: 'first_bloom', dayNumber: 1, earnedAt: new Date() },
        { type: 'first_bloom', dayNumber: 2, earnedAt: new Date() },
      ];
      
      const result = engine.evaluateWeek(triggers);
      
      expect(result.handType).toBe('pair');
      expect(result.multiplier).toBe(2);
    });
    
    it('detects three of a kind over pair', () => {
      const triggers = [
        { type: 'perfect_read', dayNumber: 1, earnedAt: new Date() },
        { type: 'perfect_read', dayNumber: 2, earnedAt: new Date() },
        { type: 'perfect_read', dayNumber: 3, earnedAt: new Date() },
        { type: 'first_bloom', dayNumber: 4, earnedAt: new Date() },
        { type: 'first_bloom', dayNumber: 5, earnedAt: new Date() },
      ];
      
      const result = engine.evaluateWeek(triggers);
      
      // Full house beats three of a kind
      expect(result.handType).toBe('full_house');
      expect(result.multiplier).toBe(15);
    });
  });
});

// Integration test example
describe('Betting Flow', () => {
  it('completes full betting cycle', async () => {
    const { gameState, bettingSystem } = createTestGame();
    
    // Place bets
    bettingSystem.placeBet('water', 'raise', 100);
    bettingSystem.placeBet('sun', 'fold', 0);
    
    // Simulate day completion
    gameState.advanceToResolution();
    
    // Resolve bets
    const results = bettingSystem.resolveBets(gameState.pots);
    
    expect(results).toHaveLength(2);
    expect(results[0].potId).toBe('water');
    expect(results[1].potId).toBe('sun');
    expect(results[1].payout).toBe(0); // Fold always 0
  });
});

Code Review Checklist

## Code Review Checklist

### Correctness
- [ ] Logic is correct and handles edge cases
- [ ] No off-by-one errors
- [ ] Null/undefined handled appropriately
- [ ] Async operations handle errors

### Type Safety
- [ ] No `any` types without justification
- [ ] Proper use of generics
- [ ] Return types explicit on public APIs
- [ ] Zod schemas match TypeScript types

### Performance
- [ ] No unnecessary re-renders (React.memo where needed)
- [ ] Large lists are virtualized
- [ ] Expensive calculations are memoized
- [ ] No memory leaks (cleanup in useEffect)

### Security
- [ ] User input is validated
- [ ] No secrets in client code
- [ ] Server validates all mutations
- [ ] Rate limiting considered

### Maintainability
- [ ] Functions are small and focused
- [ ] Clear variable/function names
- [ ] Comments explain "why", not "what"
- [ ] No magic numbers

### Testing
- [ ] Unit tests for logic
- [ ] Edge cases covered
- [ ] Tests are readable

### Accessibility
- [ ] Interactive elements are keyboard accessible
- [ ] ARIA labels where needed
- [ ] Color contrast sufficient
- [ ] Focus management correct