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+# CLAUDE.md
+
+This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.
+
+## Overview
+
+Ghostfolio is an open-source wealth management application (AGPL-3.0). It is structured as an **Nx monorepo** with two apps and two shared libraries.
+
+## Development Setup
+
+### Prerequisites
+
+- Node.js `>=22.18.0` (see `.nvmrc`)
+- Docker (for PostgreSQL and Redis)
+
+### Initial Setup
+
+```bash
+cp .env.dev .env            # fill in passwords and secrets
+npm install
+docker compose -f docker/docker-compose.dev.yml up -d
+npm run database:setup      # push schema + seed
+```
+
+### Running Locally
+
+```bash
+npm run start:server        # NestJS API on :3333
+npm run start:client        # Angular client on https://localhost:4200/en
+```
+
+Open https://localhost:4200/en. The first registered user gets the `ADMIN` role.
+
+For other languages, change `--configuration=development-en` to e.g. `--configuration=development-de` in `package.json`.
+
+## Commands
+
+| Task | Command |
+|---|---|
+| Lint all | `npm run lint` |
+| Test all | `npm test` |
+| Test API only | `npm run test:api` |
+| Test common lib | `npm run test:common` |
+| Test UI lib | `npm run test:ui` |
+| Test single file | `nx run api:test --test-file <filename>.spec.ts` |
+| Production build | `npm run build:production` |
+| Storybook | `npm run start:storybook` |
+| DB schema sync (dev) | `npm run database:push` |
+| DB migration (prod) | `npm run prisma migrate dev --name <name>` |
+| DB GUI | `npm run database:gui` |
+
+Tests require the `.env.example` env vars; the `npm test` script handles this via `dotenv-cli`.
+
+## Architecture
+
+### Monorepo Layout
+
+```
+apps/
+  api/      - NestJS backend
+  client/   - Angular 21 frontend
+libs/
+  common/   - shared interfaces, DTOs, enums, helpers, routes, permissions
+  ui/       - shared Angular component library (used by client + Storybook)
+```
+
+### TypeScript Path Aliases
+
+| Alias | Resolves to |
+|---|---|
+| `@ghostfolio/api/*` | `apps/api/src/*` |
+| `@ghostfolio/client/*` | `apps/client/src/app/*` |
+| `@ghostfolio/common/*` | `libs/common/src/lib/*` |
+| `@ghostfolio/ui/*` | `libs/ui/src/lib/*` |
+
+### Backend (`apps/api`)
+
+NestJS application with feature modules under `apps/api/src/app/` (one directory per domain: `account`, `portfolio`, `user`, `auth`, `admin`, `activities`, `import`, `export`, etc.) and cross-cutting services under `apps/api/src/services/`:
+
+- **`data-provider/`** — abstracted market data layer with pluggable providers: AlphaVantage, CoinGecko, EOD Historical Data, Financial Modeling Prep, Ghostfolio (cloud), Google Sheets, Manual, RapidAPI, YahooFinance. `DataProviderService` dispatches to the correct provider per symbol.
+- **`queues/`** — Bull background job queues: `data-gathering`, `portfolio-snapshot`, `statistics-gathering`.
+- **`prisma/`** — Prisma ORM service wrapping PostgreSQL.
+- **`exchange-rate-data/`** — currency conversion.
+- **`cron/`** — scheduled tasks.
+
+Redis is used for caching (`redis-cache` module) and as the Bull queue backend.
+
+### Frontend (`apps/client`)
+
+Angular application with lazy-loaded routes defined in [`apps/client/src/app/app.routes.ts`](apps/client/src/app/app.routes.ts). Routes are typed via `internalRoutes` / `publicRoutes` from `@ghostfolio/common/routes/routes`. The `AuthGuard` protects authenticated pages.
+
+### Shared Libraries
+
+- **`libs/common`** — `permissions.ts` (role/permission model), `config.ts` (constants, queue names, feature flags), `interfaces/`, `enums/`, `dtos/`, `routes/`, `helper.ts`, `calculation-helper.ts`.
+- **`libs/ui`** — standalone Angular components (charts, tables, dialogs, etc.) consumed by the client.
+
+### Database
+
+PostgreSQL via Prisma. Schema is at [`prisma/schema.prisma`](prisma/schema.prisma). Key models: `User`, `Account`, `Order` (activities/trades), `SymbolProfile`, `MarketData`, `Platform`, `Tag`, `Access`.
+
+## Feature Flags
+
+**Experimental features** are gated in two places:
+
+- **Backend**: remove a permission with `without()` in `UserService`
+- **Frontend**: wrap template blocks with `@if (user?.settings?.isExperimentalFeatures) {}`
+
+The Bull Board UI is enabled via `ENABLE_FEATURE_BULL_BOARD=true` in the environment.
+
+## Environment Variables
+
+See [`.env.example`](.env.example) for required variables. Key ones: `DATABASE_URL`, `REDIS_HOST`, `REDIS_PORT`, `REDIS_PASSWORD`, `ACCESS_TOKEN_SALT`, `JWT_SECRET_KEY`.