SqlAggregateStore

A Domain.AggregateStore over SqlEventLog.

Source: packages/paykit/src/Store/SqlAggregateStore.ts Kind: Primitive

A Domain.AggregateStore over SqlEventLog.

The log is the truth; this adapter is what keeps it that way. Each of the five guarantees has exactly one place in this file:

1. One writer per account — a commit runs in one transaction, so two commands on one instance serialize at the write. A decision taken outside that transaction carries the version it was made on: if the log moved, the append refuses it and the command is decided again, rather than published over a state it never saw.
2. Dedupe by commandId — a replay finds the stored receipt and returns it without deciding again, and append refuses a second write of the same id, so a retried webhook cannot become a second charge.
3. Atomic commits — events, state, receipt and deliveries land in one transaction: a crash leaves all of a command or none of it.
4. At-least-once delivery, in order — deliveries go to the outbox in the same transaction and are marked delivered only after their target accepted them, so a crash between commit and delivery replays.
5. schedule and tail — a scheduled command is a row with a due time, so it survives a restart; a live read polls, which is the correct mechanism on a store another process may be committing to.

decide, evolve and routing stay in the kernel: kit.handle produces the events, state, reply and deliveries, and this store only persists them.

Hosting a model on SQLite

const log = SqlEventLog(sql, { now: () => Date.now() });
const platform = Paykit.SqlPlatform(log);
yield* Bank.layer(BankHandlers).pipe(Effect.provide(platform));