@pg-outbox/effect

The @pg-outbox/core protocol as an Effect service over @pg-txmode/effect's layers (SqlClient). make({ outbox }) builds the outbox; enqueue and holdClaim require InTransaction in their type, which only transaction(...) provides, so a message cannot be written outside the business transaction; a lost claim is a typed value; ack, release and bury join the caller's transaction when there is one.

npm i @pg-outbox/effect@alpha @pg-outbox/core@alpha effect@">=4.1.0 <4.2.0"

An alpha: no promise of compatibility between alphas; install with @alpha. effect is a peer at >=4.1.0 <4.2.0 because the adapter uses Effect's unstable modules, which may break in a minor release (a caret would admit 4.2). @pg-txmode/effect is an exact dependency and itself needs @effect/sql-pg at the same range.

What a Hyperdrive yes covers

make runs the mode check and fails with OperationRefusedError for an operation the mode cannot honour or that is only unverified (allowUnverified: true accepts that). Behind Cloudflare Hyperdrive every operation is yes because of one recorded run with these conditions: caching enabled (the default), Workers Free plan, one Worker placed aws:eu-central-1, 24 sockets, a Neon direct endpoint (PostgreSQL 18.6), 20 rounds of each race, no LISTEN, no session advisory lock. Not covered: caching disabled, the pooled Neon endpoint, another plan, region or origin, a long or loaded run. The built outbox has measuredUnder: the runs its yes stands on, each "measured on (the recorded run: 2026-10-30)" with the conditions and the evidence file; log it where you pick a mode. Supavisor has no run and is refused unless you accept unverified.

Source, specs and evidence: https://github.com/phibkro/pg-outbox. Licence: Apache-2.0.