Persistence & Server

PostgreSQL CAS, changeId, owner_epoch, snapshots, and the reference WebSocket host.

Persistence is a port on lextrix-change. The reference implementation that talks to a real database is lextrix-server (PostgreSQL + WebSocket).

Your app still owns login, TLS, and billing. Lextrix owns accept rules and compare-and-append.

Plain text

Version → compareAndAppend → PostgreSQL

Writes succeed only when the durable HEAD still matches what the writer expected. That stops two workers from overwriting each other.

Option	Meaning
`changeId`	Same id twice → no duplicate Version
`ownerEpoch`	Stale owner → reject (`stale_owner`)

Plain text

OT accept → Handle.apply → compareAndAppend → ACK + broadcast

If CAS fails: rehydrate, skip the history ACK, skip the broadcast.

The reference schema includes document_heads, versions, change_ids, and document_ownership. Snapshot / archive tables show up when you compact history. A snapshot is a checkpoint at a Version — not a second HEAD. Do not truncate history until archive succeeds.

InMemoryAuthoritativePersistence is for tests and demos, not production.

See also Collaboration.

Persistence is a port on lextrix-change. The reference implementation that talks to a real database is lextrix-server (PostgreSQL + WebSocket).

Your app still owns login, TLS, and billing. Lextrix owns accept rules and compare-and-append.

Plain text

Version → compareAndAppend → PostgreSQL

Writes succeed only when the durable HEAD still matches what the writer expected. That stops two workers from overwriting each other.

Option	Meaning
`changeId`	Same id twice → no duplicate Version
`ownerEpoch`	Stale owner → reject (`stale_owner`)

Plain text

OT accept → Handle.apply → compareAndAppend → ACK + broadcast

If CAS fails: rehydrate, skip the history ACK, skip the broadcast.

InMemoryAuthoritativePersistence is for tests and demos, not production.