Module json_store 

JsonFileStore — a durable StateStore backed by a single JSON file.

This is the simplest real-durability backend: the framework’s risk snapshots (per-symbol SessionPnl / CircuitBreaker and the account PortfolioRisk latch) survive a restart, so a halted daily session or a tripped breaker isn’t forgotten when the bot reboots. Wire it with Bot::with_state_store.

Writes are write-through and atomic: every save (and flush) serialises the full map to a sibling temp file and renames it over the target, so a crash mid-write can’t corrupt the store — you either keep the previous good file or get the new one. Saves are infrequent (one per realised trade) and the payload is tiny (a handful of symbols), so rewriting the whole file each time is cheap.

For higher write volumes or multi-process access, a sqlite/Postgres backend (another StateStore impl) is the next step — the framework only depends on the trait.

Structs

JsonFileStore

A StateStore that persists snapshots to a JSON file on disk.