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+# CLAUDE.md
+
+## Project Overview
+
+**GridTip** is an F1 season tipping application where users predict race outcomes and compete with friends in groups.
+
+### Core Concepts
+
+- **Groups**: Users create or join groups to compete with friends
+- **Predictions/Tips**: Users predict race outcomes (pole, P1, P10, last place, sprint results, etc.)
+- **Cutoff System**: Tips lock before qualifying/sprint qualifying
+- **Leaderboard**: Track standings and compare predictions with group members
+- **Admin Controls**: Group admins can manage tips and manually override scoring
+- **Championship Predictions**: Season-long predictions for driver and constructor championships
+
+### Data Source
+
+All F1 data (races, drivers, constructors, results) comes from the **Jolpica F1 API**:
+
+- API Base: `https://api.jolpi.ca/ergast/f1/`
+- Documentation: [jolpica-f1 API docs](https://github.com/jolpica/jolpica-f1/blob/main/docs/README.md)
+- Updated via protected API endpoints (see API Routes section)
+
+---
+
+## Tech Stack
+
+### Core Framework
+
+- **Next.js** 15.5.2 (App Router, React Server Components)
+- **React** 19.1.0
+- **TypeScript** 5.x (strict mode)
+- **Bun** (runtime and package manager)
+
+### Database & ORM
+
+- **Turso** (SQLite edge database)
+- **Drizzle ORM**
+- **Convention**: `snake_case` for database columns
+
+### Authentication
+
+- **better-auth**
+- **Google OAuth** provider
+
+### UI & Styling
+
+- **Tailwind CSS** 4.x
+- **shadcn/ui** (New York style)
+- **Lucide React** for icons
+
+### Forms & Validation
+
+- **react-hook-form**
+- **Zod** 4 for schema validation
+
+### Other Key Libraries
+
+- **@tanstack/react-table** 8.21.3 (admin tables)
+- **date-fns** 4.1.0 (date manipulation)
+- **ofetch** 1.4.1 (HTTP client)
+- **sonner** 2.0.7 (toast notifications)
+- **marked** 16.4.0 (markdown parsing)
+
+### Development Tools
+
+- **Vitest** 3.2.4 (testing with jsdom)
+- **ESLint** 9.x + Prettier
+- **drizzle-kit** (migrations)
+
+---
+
+## Database Schema
+
+### Application Tables
+
+#### `groups`
+
+```typescript
+{
+  id: string (cuid2, PK)
+  name: string
+  adminUser: string (FK → user.id)
+  createdAt: timestamp
+  cutoffInMinutes: number (default: 180)
+  iconName: enum (default: 'lucide:users')
+}
+```
+
+#### `group_members`
+
+```typescript
+{
+  id: string (cuid2, PK)
+  groupId: string (FK → groups.id, CASCADE)
+  userId: string (FK → user.id, CASCADE)
+  joinedAt: timestamp
+}
+```
+
+#### `races`
+
+```typescript
+{
+  id: string (circuit ID, PK)
+  country: string
+  locality: string
+  round: number
+  circuitName: string
+  raceName: string
+  grandPrixDate: timestamp
+  qualifyingDate: timestamp
+  sprintDate: timestamp | null
+  sprintQualifyingDate: timestamp | null
+  lastUpdated: timestamp
+  created: timestamp
+}
+```
+
+#### `drivers`
+
+```typescript
+{
+  id: string (PK)
+  permanentNumber: string
+  fullName: string
+  givenName: string
+  familyName: string
+  nationality: string
+  constructorId: string (FK → constructors.id, CASCADE)
+  lastUpdated: timestamp
+  created: timestamp
+}
+```
+
+#### `constructors`
+
+```typescript
+{
+  id: string(PK)
+  name: string
+  nationality: string
+  created: timestamp
+  lastUpdated: timestamp
+}
+```
+
+#### `predictions`
+
+```typescript
+{
+  id: string (cuid2, PK)
+  userId: string (FK → user.id, CASCADE)
+  groupId: string (FK → groups.id, CASCADE)
+  isForChampionship: boolean (default: false)
+  raceId: string | null (FK → races.id, CASCADE)
+  createdAt: timestamp
+
+  // Indexes on: userId, groupId, isForChampionship, raceId
+}
+```
+
+#### `prediction_entries`
+
+```typescript
+{
+  id: string (cuid2, PK)
+  predictionId: string (FK → predictions.id, CASCADE)
+  position: enum (PREDICTION_FIELDS)
+  driverId: string | null (FK → drivers.id, CASCADE)
+  constructorId: string | null (FK → constructors.id, CASCADE)
+  overwriteTo: 'countAsCorrect' | 'countAsIncorrect' | null
+  createdAt: timestamp
+
+  // Unique constraint: (predictionId, position)
+}
+```
+
+#### `results`
+
+```typescript
+{
+  id: string (cuid2, PK)
+  raceId: string (FK → races.id, CASCADE)
+  driverId: string | null (FK → drivers.id, CASCADE)
+  constructorId: string (FK → constructors.id, CASCADE)
+  sprint: number | null
+  grid: number | null
+  position: number | null
+  points: number
+  status: string
+  addedAt: timestamp
+  updatedAt: timestamp
+}
+```
+
+### Authentication Tables
+
+#### `user`
+
+```typescript
+{
+  id: string(PK)
+  name: string
+  email: string(unique)
+  emailVerified: boolean
+  image: string | null
+  createdAt: timestamp
+  updatedAt: timestamp
+}
+```
+
+#### `session`
+
+```typescript
+{
+  id: string (PK)
+  token: string (unique)
+  expiresAt: timestamp
+  ipAddress: string | null
+  userAgent: string | null
+  userId: string (FK → user.id, CASCADE)
+  createdAt: timestamp
+  updatedAt: timestamp
+}
+```
+
+#### `account`
+
+```typescript
+{
+  id: string (PK)
+  accountId: string
+  providerId: string
+  userId: string (FK → user.id, CASCADE)
+  accessToken: string | null
+  refreshToken: string | null
+  idToken: string | null
+  accessTokenExpiresAt: timestamp | null
+  refreshTokenExpiresAt: timestamp | null
+  scope: string | null
+  password: string | null
+  createdAt: timestamp
+  updatedAt: timestamp
+}
+```
+
+#### `verification`
+
+```typescript
+{
+  id: string(PK)
+  identifier: string
+  value: string
+  expiresAt: timestamp
+  createdAt: timestamp
+  updatedAt: timestamp
+}
+```
+
+### Prediction Fields Constants
+
+```typescript
+// Race prediction fields
+DRIVER_RACE_PREDICTION_FIELDS = ['sprintP1', 'pole', 'p1', 'p10', 'last']
+CONSTRUCTOR_RACE_PREDICTION_FIELDS = ['constructorWithMostPoints']
+
+// Championship prediction fields
+CHAMPIONSHIP_PREDICTION_FIELDS = [
+  'championshipConstructor',
+  'championshipDriver',
+]
+
+// Cutoff reference mapping
+CUTOFF_REFERENCE_KEY = {
+  pole: 'qualifyingDate',
+  p1: 'qualifyingDate',
+  p10: 'qualifyingDate',
+  last: 'qualifyingDate',
+  constructorWithMostPoints: 'qualifyingDate',
+  sprintP1: 'sprintQualifyingDate',
+}
+```
+
+**Location**: `/home/user/gridtip/db/schema/schema.ts`
+
+### Key Functions (DAL - Data Access Layer)
+
+Location: `/home/user/gridtip/lib/dal.ts`
+
+```typescript
+// Verify session (cached, redirects if not authenticated)
+await verifySession()
+
+// Optional session retrieval
+const session = await getMaybeSession()
+
+// Get member status (Admin | Member)
+const status = await getMemberStatus(groupId)
+
+// Verify admin status (cached)
+await verifyIsAdmin(groupId)
+```
+
+### Protected Routes
+
+**Middleware** (`/home/user/gridtip/app/middleware.ts`):
+
+- Protected path: `/tipping/*`
+- Redirects to: `/auth?origin=not-logged-in`
+
+### API Route Protection
+
+Update endpoints use Basic Auth (`validateToken()` in `/home/user/gridtip/app/api/utils.ts`):
+
+- Requires `UPDATES_USER` and `UPDATES_PASSWORD_HASH`
+- Applied to: `/api/races/update`, `/api/drivers/update`, `/api/constructors/update`, `/api/results/update`
+
+---
+
+## Code Conventions & Style
+
+### TypeScript Conventions
+
+1. **Strict mode enabled** - All TypeScript strict checks active
+2. **Path aliases**:
+   - `@/*` → project root
+   - `@@/*` → `/app` directory
+3. **Type imports**: Use `import type` for type-only imports
+4. **Database types**: Generated in `/home/user/gridtip/db/types`
+
+### Naming Conventions
+
+1. **Files & Directories**:
+   - Components: `kebab-case.tsx` (e.g., `group-switcher.tsx`)
+   - Routes: `kebab-case` (e.g., `add-tips/`)
+   - Utilities: `kebab-case.ts` (e.g., `prediction-fields.ts`)
+
+2. **Database**:
+   - Tables: `snake_case` (e.g., `group_members`)
+   - Columns: `snake_case` (enforced by Drizzle config)
+
+3. **React Components**:
+   - PascalCase (e.g., `GroupSwitcher`)
+   - Use named exports for consistency
+
+4. **Functions**:
+   - camelCase (e.g., `getMemberStatus`)
+   - Server actions: descriptive names (e.g., `createGroup`)
+
+5. **Constants**:
+   - SCREAMING_SNAKE_CASE (e.g., `DEFAULT_CUTOFF_MINS`)
+   - Enums: PascalCase (e.g., `CacheTag.Results`)
+
+### Component Organization
+
+**Colocation pattern** - Route-specific code lives with the route:
+
+```
+app/tipping/add-tips/[race-id]/
+├── page.tsx                    # Route component
+├── _components/                # Route-specific components
+│   └── tip-form.tsx
+├── actions/                    # Route-specific actions
+│   └── submit-tips.ts
+└── _utils/                     # Route-specific utilities
+    └── validation.ts
+```
+
+## Key Features & Routes
+
+### Public Routes (`app/(public)/`)
+
+- **`/`** - Landing page
+- **`/contact`** - Contact information
+
+### Standalone Routes (`app/(standalone)/`)
+
+- **`/auth`** - Authentication page (Google OAuth)
+- **`/join/[groupId]`** - Join group via shareable link
+
+### Protected Routes (`app/tipping/`)
+
+#### Dashboard (`/tipping`)
+
+**File**: `/home/user/gridtip/app/tipping/page.tsx`
+
+Dynamic cards based on state:
+
+- Join/create group prompt (if no groups)
+- Next race tipping card (with cutoff countdown)
+- Tipping status (who has/hasn't tipped)
+- Everyone's tips (accordion, locked before cutoff)
+- Previous race results
+
+#### Add Tips (`/tipping/add-tips/[race-id]`)
+
+**File**: `/home/user/gridtip/app/tipping/add-tips/[race-id]/page.tsx`
+
+- Predict: pole, P1, P10, last place, constructor with most points
+- Sprint races: also predict sprint P1
+- Cutoff enforcement (default: 180 min before qualifying)
+- Edit existing tips before cutoff
+- Form validation via Zod
+
+#### Championships (`/tipping/championships`)
+
+**File**: `/home/user/gridtip/app/tipping/championships/page.tsx`
+
+- Predict championship winner (driver)
+- Predict championship winner (constructor)
+- Season-long predictions
+
+#### Leaderboard (`/tipping/leaderboard`)
+
+**File**: `/home/user/gridtip/app/tipping/leaderboard/page.tsx`
+
+- View race results
+- Group standings
+- Past race predictions vs. actual results
+- Results comparison table
+
+#### Groups (`/tipping/groups`)
+
+**File**: `/home/user/gridtip/app/tipping/groups/page.tsx`
+
+- Create new group
+- Edit group settings (name, icon, cutoff time)
+- View group members
+- Leave group
+
+#### Group Admin (`/tipping/group-admin`)
+
+**File**: `/home/user/gridtip/app/tipping/group-admin/page.tsx`
+
+**Requires**: Admin status
+
+Features:
+
+- View all user tips in data table (@tanstack/react-table)
+- Edit/create tips on behalf of users
+- Admin overwrite system:
+  - Mark predictions as correct (`countAsCorrect`)
+  - Mark predictions as incorrect (`countAsIncorrect`)
+- Update results button (clears cache)
+
+#### Settings (`/tipping/settings`)
+
+**File**: `/home/user/gridtip/app/tipping/settings/page.tsx`
+
+- Account deletion
+- Profile information
+
+### API Routes (`app/api/`)
+
+#### Authentication
+
+- **`POST/GET /api/auth/[...all]`** - better-auth catch-all handler
+
+#### Data Updates (Protected with Basic Auth)
+
+All require `UPDATES_USER` and `UPDATES_PASSWORD_HASH`:
+
+- **`GET /api/races/update`** - Fetch and update race data from Jolpica API
+- **`GET /api/drivers/update`** - Update driver data
+- **`GET /api/constructors/update`** - Update constructor data
+- **`GET /api/results/update`** - Update race results
+
+**API Utils** (`app/api/utils.ts`):
+
+```typescript
+fetchJolpica() // ofetch instance for Jolpica API
+validateToken() // Basic auth validation
+createResponse() // Standardized JSON responses
+areFieldsTheSame() // Compare objects for updates
+```
+
+---
+
+## Common Patterns
+
+### React Server Components (Default)
+
+Most page and layout components are RSCs:
+
+```typescript
+// ✅ Server Component (default)
+export default async function Page() {
+  const data = await db.query.races.findMany()
+  return <div>{/* ... */}</div>
+}
+```
+
+### Client Components
+
+Use `"use client"` directive when needed:
+
+```typescript
+// ✅ Client Component
+'use client'
+
+import { useState } from 'react'
+
+export function Counter() {
+  const [count, setCount] = useState(0)
+  // ...
+}
+```
+
+**When to use Client Components**:
+
+- Forms with `react-hook-form`
+- Interactive UI (combobox, dialogs)
+- Components using hooks (`useState`, `useEffect`)
+- Event handlers
+
+### Server Actions
+
+**Pattern** (see `/home/user/gridtip/actions/`):
+
+```typescript
+'use server'
+
+import { z } from 'zod'
+import { verifySession } from '@/lib/dal'
+import { db } from '@/db'
+import { ServerResponse } from '@/types'
+
+const schema = z.object({
+  name: z.string().min(1),
+})
+
+export async function createGroup(
+  input: z.infer<typeof schema>,
+): Promise<ServerResponse> {
+  // 1. Verify session
+  const { user } = await verifySession()
+
+  // 2. Validate input
+  const validatedInput = schema.parse(input)
+
+  // 3. Database operations
+  const [group] = await db
+    .insert(groups)
+    .values({
+      name: validatedInput.name,
+      adminUser: user.id,
+    })
+    .returning()
+
+  // 4. Return standardized response
+  return { ok: true, message: 'Group created' }
+}
+```
+
+**Response type**:
+
+```typescript
+type ServerResponse = {
+  ok: boolean
+  message: string
+}
+```
+
+### Data Fetching & Caching
+
+**Pattern 1: `cache()` for request memoization**
+
+```typescript
+import { cache } from 'react'
+
+export const getDrivers = cache(async () => {
+  return db.query.drivers.findMany()
+})
+```
+
+**Pattern 2: `unstable_cache()` for persistence**
+Cache data aggressively. Most data only updates on specific triggers.
+
+```typescript
+import { unstable_cache } from 'next/cache'
+import { CacheTag } from '@/constants/cache'
+
+export const getRaces = unstable_cache(
+  async () => db.query.races.findMany(),
+  [],
+  { tags: [CacheTag.Races] },
+)
+```
+
+**Cache Tags** (`/home/user/gridtip/constants/cache.ts`):
+
+```typescript
+enum CacheTag {
+  Results = 'results',
+  Constructors = 'constructors',
+  Drivers = 'drivers',
+  Races = 'races',
+  Predictions = 'predictions',
+}
+```
+
+**Revalidation**:
+
+```typescript
+import { revalidateTag } from 'next/cache'
+import { CacheTag } from '@/constants/cache'
+
+// Revalidate specific cache tag
+revalidateTag(CacheTag.Races)
+```
+
+### Component Composition
+
+**Pattern**: Small, focused components
+
+```typescript
+// ✅ Good - Composable components
+function CardJoinGroup() {
+  return <Card>{/* ... */}</Card>
+}
+
+function CardTipNext({ race, groupId }: Props) {
+  return <Card>{/* ... */}</Card>
+}
+
+export default function Dashboard() {
+  return (
+    <div>
+      {!hasGroups && <CardJoinGroup />}
+      {currentRace && <CardTipNext race={currentRace} groupId={groupId} />}
+    </div>
+  )
+}
+```
+
+### Type Safety
+
+**Database types** (`/home/user/gridtip/db/types`):
+
+```typescript
+import { Database } from '@/db/types'
+
+type User = Database.User
+type Race = Database.Race
+```
+
+**Const assertions for type narrowing**:
+
+```typescript
+export const PREDICTION_FIELDS = ['pole', 'p1', 'p10', 'last'] as const
+
+type PredictionField = (typeof PREDICTION_FIELDS)[number]
+// Type: 'pole' | 'p1' | 'p10' | 'last'
+```
+
+---
+
+## Common Tasks
+
+### Adding a New Route
+
+1. **Create route directory**:
+
+   ```
+   app/tipping/my-feature/
+   ├── page.tsx
+   ├── _components/
+   ```
+
+2. **Add to navigation** (if needed):
+   - Edit: `components/nav-main.tsx`
+   - Add route to `items` array
+
+3. **Add breadcrumb** (if needed):
+   - Edit: `components/breadcrumbs.tsx`
+
+### Adding a New Database Table
+
+1. **Define schema** in `/home/user/gridtip/db/schema/schema.ts`:
+
+   ```typescript
+   export const myTable = sqliteTable('my_table', {
+     id: text('id')
+       .primaryKey()
+       .$defaultFn(() => createId()),
+     name: text('name').notNull(),
+     createdAt: integer('created_at', { mode: 'timestamp' })
+       .notNull()
+       .$defaultFn(() => new Date()),
+   })
+   ```
+
+2. **Generate migration**:
+
+   ```bash
+   bun run db:generate
+   ```
+
+3. **Review migration** in `db/migrations/`
+
+4. **Apply migration**:
+
+   ```bash
+   bun run db:migrate
+   ```
+
+5. **Add to Drizzle queries** (optional):
+   ```typescript
+   // In db/index.ts
+   export const db = drizzle(client, {
+     schema: { ...authSchema, myTable },
+   })
+   ```
+
+### Adding a New Server Action
+
+1. **Create file** in `/actions/` or route-specific `actions/`:
+
+   ```typescript
+   'use server'
+
+   import { z } from 'zod'
+   import { verifySession } from '@/lib/dal'
+   import { ServerResponse } from '@/types'
+
+   const schema = z.object({
+     // Define schema
+   })
+
+   export async function myAction(
+     input: z.infer<typeof schema>,
+   ): Promise<ServerResponse> {
+     const { user } = await verifySession()
+     const validated = schema.parse(input)
+
+     // Perform action
+
+     return { ok: true, message: 'Success' }
+   }
+   ```
+
+2. **Use in component**:
+
+   ```typescript
+   import { myAction } from '@/actions/my-action'
+
+   const result = await myAction({
+     /* data */
+   })
+   if (result.ok) {
+     toast.success(result.message)
+   }
+   ```
+
+### Adding a New shadcn/ui Component
+
+```bash
+# Install individual component
+bunx shadcn@latest add [component-name]
+```
+
+**Example**:
+
+```bash
+bunx shadcn@latest add tabs
+```
+
+**Configuration**: `components.json`
+
+### Invalidating Cache
+
+```typescript
+import { revalidateTag } from 'next/cache'
+import { CacheTag } from '@/constants/cache'
+
+// Invalidate specific tag
+revalidateTag(CacheTag.Predictions)
+
+// Clear multiple tags
+revalidateTag(CacheTag.Results)
+revalidateTag(CacheTag.Predictions)
+```
+
+---
+
+## Important File References
+
+### Core Configuration
+
+| File                | Purpose                | Location                               |
+| ------------------- | ---------------------- | -------------------------------------- |
+| `package.json`      | Dependencies & scripts | `/home/user/gridtip/package.json`      |
+| `tsconfig.json`     | TypeScript config      | `/home/user/gridtip/tsconfig.json`     |
+| `next.config.ts`    | Next.js config         | `/home/user/gridtip/next.config.ts`    |
+| `drizzle.config.ts` | Database config        | `/home/user/gridtip/drizzle.config.ts` |
+| `eslint.config.mjs` | Linting rules          | `/home/user/gridtip/eslint.config.mjs` |
+| `.prettierrc`       | Code formatting        | `/home/user/gridtip/.prettierrc`       |
+| `vitest.config.mts` | Test config            | `/home/user/gridtip/vitest.config.mts` |
+| `components.json`   | shadcn config          | `/home/user/gridtip/components.json`   |
+
+### Database
+
+| File             | Purpose         | Location                                      |
+| ---------------- | --------------- | --------------------------------------------- |
+| `schema.ts`      | Main schema     | `/home/user/gridtip/db/schema/schema.ts`      |
+| `auth-schema.ts` | Auth schema     | `/home/user/gridtip/db/schema/auth-schema.ts` |
+| `index.ts`       | DB client       | `/home/user/gridtip/db/index.ts`              |
+| `migrations/`    | Migration files | `/home/user/gridtip/db/migrations/`           |
+
+### Authentication
+
+| File             | Purpose            | Location                                |
+| ---------------- | ------------------ | --------------------------------------- |
+| `auth.ts`        | Server auth config | `/home/user/gridtip/lib/auth.ts`        |
+| `auth-client.ts` | Client auth        | `/home/user/gridtip/lib/auth-client.ts` |
+| `dal.ts`         | Data Access Layer  | `/home/user/gridtip/lib/dal.ts`         |
+| `middleware.ts`  | Route protection   | `/home/user/gridtip/app/middleware.ts`  |
+
+### Constants
+
+| File            | Purpose        | Location                                     |
+| --------------- | -------------- | -------------------------------------------- |
+| `index.ts`      | Core constants | `/home/user/gridtip/constants/index.ts`      |
+| `cache.ts`      | Cache tags     | `/home/user/gridtip/constants/cache.ts`      |
+| `icon-names.ts` | Group icons    | `/home/user/gridtip/constants/icon-names.ts` |
+
+### Utilities
+
+| File                   | Purpose            | Location                                            |
+| ---------------------- | ------------------ | --------------------------------------------------- |
+| `utils.ts`             | General utils (cn) | `/home/user/gridtip/lib/utils.ts`                   |
+| `groups.ts`            | Group utilities    | `/home/user/gridtip/lib/utils/groups.ts`            |
+| `races.ts`             | Race utilities     | `/home/user/gridtip/lib/utils/races.ts`             |
+| `prediction-fields.ts` | Prediction utils   | `/home/user/gridtip/lib/utils/prediction-fields.ts` |
+| `country-flag.ts`      | Flag utilities     | `/home/user/gridtip/lib/utils/country-flag.ts`      |
+
+### API Routes
+
+| File                           | Purpose             | Location                                                  |
+| ------------------------------ | ------------------- | --------------------------------------------------------- |
+| `auth/[...all]/route.ts`       | Auth endpoints      | `/home/user/gridtip/app/api/auth/[...all]/route.ts`       |
+| `races/update/route.ts`        | Update races        | `/home/user/gridtip/app/api/races/update/route.ts`        |
+| `drivers/update/route.ts`      | Update drivers      | `/home/user/gridtip/app/api/drivers/update/route.ts`      |
+| `constructors/update/route.ts` | Update constructors | `/home/user/gridtip/app/api/constructors/update/route.ts` |
+| `results/update/route.ts`      | Update results      | `/home/user/gridtip/app/api/results/update/route.ts`      |
+| `utils.ts`                     | API utilities       | `/home/user/gridtip/app/api/utils.ts`                     |
+
+### Main Pages
+
+| Route                         | File Location                                                 |
+| ----------------------------- | ------------------------------------------------------------- |
+| `/`                           | `/home/user/gridtip/app/(public)/page.tsx`                    |
+| `/auth`                       | `/home/user/gridtip/app/(standalone)/auth/page.tsx`           |
+| `/join/[groupId]`             | `/home/user/gridtip/app/(standalone)/join/[groupId]/page.tsx` |
+| `/tipping`                    | `/home/user/gridtip/app/tipping/page.tsx`                     |
+| `/tipping/add-tips/[race-id]` | `/home/user/gridtip/app/tipping/add-tips/[race-id]/page.tsx`  |
+| `/tipping/championships`      | `/home/user/gridtip/app/tipping/championships/page.tsx`       |
+| `/tipping/groups`             | `/home/user/gridtip/app/tipping/groups/page.tsx`              |
+| `/tipping/group-admin`        | `/home/user/gridtip/app/tipping/group-admin/page.tsx`         |
+| `/tipping/leaderboard`        | `/home/user/gridtip/app/tipping/leaderboard/page.tsx`         |
+| `/tipping/settings`           | `/home/user/gridtip/app/tipping/settings/page.tsx`            |
+
+### Key Components
+
+| Component      | Location                                           |
+| -------------- | -------------------------------------------------- |
+| App Sidebar    | `/home/user/gridtip/components/app-sidebar.tsx`    |
+| App Header     | `/home/user/gridtip/components/app-header.tsx`     |
+| Group Switcher | `/home/user/gridtip/components/group-switcher.tsx` |
+| Driver Option  | `/home/user/gridtip/components/driver-option.tsx`  |
+| Select Driver  | `/home/user/gridtip/components/select-driver.tsx`  |
+| Breadcrumbs    | `/home/user/gridtip/components/breadcrumbs.tsx`    |
+| UI Components  | `/home/user/gridtip/components/ui/*`               |
+
+### Actions
+
+| Action       | Location                                     |
+| ------------ | -------------------------------------------- |
+| Create Group | `/home/user/gridtip/actions/create-group.ts` |
+| Join Group   | `/home/user/gridtip/actions/join-group.ts`   |
+| Edit Group   | `/home/user/gridtip/actions/edit-group.ts`   |
+| Delete User  | `/home/user/gridtip/actions/delete-user.ts`  |
+
+### Scripts
+
+| Script       | Location                                     |
+| ------------ | -------------------------------------------- |
+| Save Avatars | `/home/user/gridtip/scripts/save-avatars.ts` |
+
+### Tests
+
+| Test         | Location                                      |
+| ------------ | --------------------------------------------- |
+| Cutoff Tests | `/home/user/gridtip/__tests__/cutoff.test.ts` |
+
+---
+
+## Tips for AI Assistants
+
+### When Making Changes
+
+1. **Always check authentication** - Most routes require `verifySession()`
+2. **Use proper cache tags** - Revalidate caches when data changes
+3. **Follow server/client boundaries** - Mark client components with `'use client'`
+4. **Validate with Zod** - All user inputs should be validated
+5. **Return ServerResponse** - Server actions should return `{ ok, message }`
+6. **Check cutoff logic** - Race tips have time-based cutoffs
+7. **Test with sprint races** - Sprint weekends have different prediction fields
+8. **Respect admin permissions** - Use `verifyIsAdmin()` for admin-only features
+
+### When Debugging
+
+1. **Check middleware** - Authentication issues often stem from middleware
+2. **Verify cache tags** - Stale data might be cached
+3. **Check database migrations** - Schema changes need migrations
+4. **Review Zod schemas** - Validation errors might be from schema mismatches
+5. **Check environment variables** - Missing vars cause auth/db failures
+6. **Review DAL functions** - Session and permission logic centralized in DAL
+
+### When Adding Features
+
+1. **Use existing patterns** - Follow established patterns in codebase
+2. **Colocate route-specific code** - Use `_components/`, `actions/`, `_utils/`
+3. **Add cache tags** - For data that needs invalidation
+4. **Update navigation** - Add to sidebar/breadcrumbs if needed
+5. **Write tests** - Add to `__tests__/` directory
+6. **Document constants** - Add to `/constants/` if reusable
+
+---
+
+## Related Resources
+
+- **Next.js Docs**: https://nextjs.org/docs
+- **Drizzle ORM**: https://orm.drizzle.team/
+- **better-auth**: https://better-auth.com/
+- **shadcn/ui**: https://ui.shadcn.com/
+- **Jolpica F1 API**: https://github.com/jolpica/jolpica-f1/blob/main/docs/README.md
+- **Turso Docs**: https://docs.turso.tech/