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CLAUDE.md

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+# Claude - blockchain-core
+
+## Projet
+Rust workspace : blockchain core library + REST API node.
+Partie d'un ecosysteme de 3 repos (blockchain-core, blockchain-cli, blockchain-flutter).
+
+## Architecture
+```
+blockchain-core/  (Rust workspace)
+├── core/         Library crate - blockchain primitives
+│   └── src/      block, chain, wallet, transaction, mining, state, persistence, config, error
+├── node/         Binary crate - axum REST API (port 3000)
+│   └── src/      main, state (Arc<RwLock>), api/ (blocks, transactions, wallets, mining, chain, errors)
+└── tests/        Integration tests
+```
+
+## Decisions techniques
+- **Account-based** (HashMap<Address, Balance>), pas UTXO
+- **SHA-256** (sha2) pour hashing
+- **Ed25519** (ed25519-dalek) pour signatures
+- **axum 0.8** pour l'API REST
+- **JSON files** pour persistence (pas de DB)
+- **u64** pour montants (comme satoshis, pas de floats)
+
+## API Endpoints (port 3000)
+- `GET /api/blocks` - List blocks (paginated)
+- `GET /api/blocks/:hash` - Block by hash
+- `POST /api/transactions` - Submit signed tx
+- `GET /api/transactions/pending` - Pending pool
+- `POST /api/wallets` - Generate wallet
+- `GET /api/wallets/:address/balance` - Balance + nonce
+- `POST /api/mine` - Mine block
+- `GET /api/mining/status` - Difficulty, reward
+- `GET /api/chain/info` - Chain info
+- `POST /api/chain/validate` - Validate chain
+- `GET /api/health` - Health check
+
+## Commandes
+```bash
+cargo build              # Build tout
+cargo test               # Tests unitaires
+cargo run -p blockchain-node  # Lancer le node
+cargo clippy             # Lint
+```
+
+## Phase actuelle
+Phase 1-3 complètes : core lib + node API implémentés.
+Prochaine étape : installer Rust, compiler, lancer les tests.
+
+## Repos liés
+- blockchain-cli (Rust CLI, HTTP only)
+- blockchain-flutter (Flutter app, HTTP only)
+
+## Gitea
+https://git.etheryale.com/StillHammer/blockchain-core