More scalable data storage

README.md

@@ -22,9 +22,9 @@ Stop the nodes with:
 docker compose -f compose.testnet.yaml down
 ```
 
-The volumes persist across stops and rebuilds. **Do not add `-v` unless you intend to delete all three ledgers.** Back up wallets separately. Protocol v4 uses a new chain identity; earlier v2/v3 ledgers and encrypted backups are not compatible. To keep old Docker data intact while trying v4, use a separate Compose project name, for example `docker compose -p wikideck-v4 -f compose.testnet.yaml up --build -d`, and use the same `-p wikideck-v4` for subsequent Compose commands. The default `docker compose up --build -d` uses [compose.yaml](compose.yaml): it starts one isolated node on port 3001 with a different volume.
+The target block interval is **15 minutes**. The volumes persist across stops and rebuilds. **Do not add `-v` unless you intend to delete all three ledgers.** Back up wallets separately. Protocol v5 uses a new chain identity; earlier v2/v3/v4 ledgers and encrypted backups are not compatible. To keep old Docker data intact while trying v5, use a separate Compose project name, for example `docker compose -p wikideck-v5 -f compose.testnet.yaml up --build -d`, and use the same `-p wikideck-v5` for subsequent Compose commands. The default `docker compose up --build -d` uses [compose.yaml](compose.yaml): it starts one isolated node on port 3001 with a different volume.
 
-For an existing host install, keep the old data directory intact and set `WIKIDECK_DATA_DIR` to a new empty directory before starting protocol v4. The node intentionally fails closed on an old ledger; it does not reset or migrate it.
+For an existing host install, keep the old data directory intact and set `WIKIDECK_DATA_DIR` to a new empty directory before starting protocol v5. The node intentionally fails closed on an old-protocol ledger; it does not reset or migrate it. An existing v5 JSON ledger is imported into SQLite on first startup and left in place as a recovery copy.
 
 ## Run on your host
 
@@ -97,7 +97,7 @@ This mines three real blocks using disposable identities. It changes the testnet
 
 ## Network and safety limits
 
-Nodes use only explicitly configured peers; there is no discovery service or public bootstrap network. The peer, storage, and HTTP configuration is documented in [docs/testnet-consensus.md](docs/testnet-consensus.md). The implementation is experimental: it has no fees or economic security, and remains vulnerable to resource exhaustion, isolation/eclipsing, censorship, majority-hashpower attacks, and reorganizations. Storage limits are stop limits rather than a scalable production design. HTTPS, container hardening, and passing tests do not constitute a security audit.
+Nodes use only explicitly configured peers; there is no discovery service or public bootstrap network. The peer, storage, and HTTP configuration is documented in [docs/testnet-consensus.md](docs/testnet-consensus.md). The implementation is experimental: it has no fees or economic security, and remains vulnerable to resource exhaustion, isolation/eclipsing, censorship, majority-hashpower attacks, and reorganizations. The ledger now uses transactional SQLite/WAL storage and sparse per-block NFT-state deltas, but nodes still retain DAG block records in memory, rebuild state roots over the full NFT set, and revalidate all proofs at startup. It is not yet an archival-scale production design. HTTPS, container hardening, and passing tests do not constitute a security audit.
 
 Before considering any broader deployment, the protocol and cryptography would need independent audits, adversarial network testing, hardened abuse controls, and tested recovery procedures. Do not expose a public node or use valuable assets on this experimental network.