Contract-suite rows (task suite-opts-backoff-rows): the backoff-curve equivalence row and the deferred enqueue-opts clock legs. backoff_curve_equivalence — the equal-jitter exponential pinned as the range, not a jitter label (ADR-010 §3): claim → retry(err, None) cycles on a backoff_base_s = 2 queue land the ranges [1,2], [2,4], [4,8] across attempts 1–3, each computed delay read back through get_job's resolved run_at minus a clock read taken before the retry — the lower bound race-free (the retry's internal clock read cannot precede the suite's, so the observed value over-reads the delay, never under-reads) and the upper bound carrying a one-second straddle tolerance for the integer-second stamp crossing a wall second; identical bounds on both engines is the equivalence pin (ADR-012 §2, the row body shared). The explicit-delay override legs ride the same row: retry(err, Some(5)) honored verbatim ([5, 6] under the same straddle tolerance) and retry(err, Some(0)) resolving ready-now per the boundary-total rule (ADR-023 §2), claimed within a bounded wait. enqueue_opts_resolution extended in place with the wave-5 legs its deferral note named — the run_at-alone literal leg (a future run_at is the row's ready time verbatim, a deterministic equality with no clock read involved; a past run_at stores the literal too and is claimable now through the run_at <= now predicate within a bounded wait, the run_at-ASC ordering making the observation unambiguous among the row's other legs) and the neither-field leg (ready at the enqueue instant, abs_diff(now) <= 5 tolerance-bounded proximity, never a tight timing assert); the deferral note replaced by the completion statement, ADR-023 §2 stamp accumulated per the convention (ADR-020 §1 governs the resolutions). Cap-leg disposition recorded in Notes for the review gate: the 1-hour cap is not suite-pinnable (capped attempts need minute-scale waits) and stays pinned engine-side on both engines' unit tests per the wave-3/4 reviews. Ready-now waits are bounded claim_one poll loops (deadline asserts only, sequential single-store drive), with the one draft defect the finding surfaced (a re-claim after the bounded wait consumed nothing; the helper returns the claimed handle) noted. Wired into both engines' suite targets (SQLite tokio test, pg harness_row!), 25 rows per column up from 24. Verified: SQLite column green server-less (25/25 suite, 189 lib), pg column green vs harness (postgres/poc@:15432 — 25/25 suite, 121 lib + 9 schema), 3 solo re-runs of each new/extended row per engine (determinism), server-less pg skips cleanly via the reachability gate, cargo test -p alkstore-sqlite -p alkstore-postgres green, clippy -D warnings, fmt clean

alkstore-postgres/tests/contract_suite.rs

@@ -163,16 +163,16 @@ async fn harness_ready() -> bool {
 
 mod rows {
     use alkstore_contract_suite::properties::{
-        concurrent_try_lock_loser_is_a_value, drop_rollback_leaves_no_ghosts,
-        duration_refusal_on_non_positive_ttl, enqueue_opts_resolution, extent_clamp_semantics,
-        in_tx_reads_see_own_writes, job_handle_validity_predicate,
-        lock_ttl_expiry_and_reacquisition, name_validation_rejects_empty_and_reserved,
-        outbox_enqueue_tx_commit_atomicity, payload_round_trip_stores_exact_encoding,
-        payload_too_large_produced_on_pg, publish_with_key_tx_commit_atomicity,
-        queue_depth_reclaim_and_dead_letter, receiver_close_and_save_arms,
-        scheduler_boundary_fires, scheduler_bounded_catchup, scheduler_leadership_discipline,
-        stream_ordering_equivalence, sweep_no_stranded_rows, trim_to_semantics,
-        wake_receiver_shapes, with_tx_panicking_closure_rolls_back,
+        backoff_curve_equivalence, concurrent_try_lock_loser_is_a_value,
+        drop_rollback_leaves_no_ghosts, duration_refusal_on_non_positive_ttl,
+        enqueue_opts_resolution, extent_clamp_semantics, in_tx_reads_see_own_writes,
+        job_handle_validity_predicate, lock_ttl_expiry_and_reacquisition,
+        name_validation_rejects_empty_and_reserved, outbox_enqueue_tx_commit_atomicity,
+        payload_round_trip_stores_exact_encoding, payload_too_large_produced_on_pg,
+        publish_with_key_tx_commit_atomicity, queue_depth_reclaim_and_dead_letter,
+        receiver_close_and_save_arms, scheduler_boundary_fires, scheduler_bounded_catchup,
+        scheduler_leadership_discipline, stream_ordering_equivalence, sweep_no_stranded_rows,
+        trim_to_semantics, wake_receiver_shapes, with_tx_panicking_closure_rolls_back,
     };
 
     use super::PgFactory;
@@ -243,6 +243,11 @@ mod rows {
         enqueue_opts_resolution,
         "row-opts-resolution"
     );
+    harness_row!(
+        row_backoff_curve_equivalence,
+        backoff_curve_equivalence,
+        "row-backoff-curve"
+    );
     harness_row!(
         row_receiver_close_and_save_arms,
         receiver_close_and_save_arms,