- impl EngineWindowState for SqliteBackend, the window family only per
ADR-012 §5's sqlite row; no pin-clause or sweep-lock body exists —
EngineFleetState is never implemented on this engine
- ensure_gc_schema creates gc_window only (never gc_pins; the embedder's
liveness table is never created — ADR-008 schema ownership)
- window_stage is a key-keyed upsert: idempotent per (key, deadline),
a re-stage at a new deadline updates the row
- window_take is one atomic DELETE … RETURNING with the <= now
boundary; future rows left in place; tableless take is a no-op read,
tableless stage surfaces the engine error (the recorded read/write
tolerance split)
- visible_after encodes as signed i64 nanoseconds from the epoch
(recorded design point; sub-second precision for test tunings)
- six clause contract tests per the ADR-012 §5 sqlite row
Verification: cargo test green (58 lib + 5 integration);
cargo clippy --all-targets -- -D warnings green; cargo fmt --check green.
Six tasks against the wave-2 contract surface as reviewed (no
amendments from the gate):
- engine-sqlite: the default kv engine — WAL + synchronous=NORMAL,
prepared statements, the indexed size column probe (B5's row shape),
has-as-EXISTS, virgin-store no-tables-yet tolerance, spawn_blocking
discipline
- engine-sqlite-window: the engine-state seam's window family only
(ADR-012 §5's reduction — gc_window, stage/take; no pin rows, no
sweep-lock body)
- store-sqlite-construction: KvEngine::Sqlite slots in, the
dual-tier/kv-only constructors with the constructor-tunable window
delay (default 5 min), ensure_gc_schema at construction, the
one-window-host posture
- store-sweep-durable-window: the sweep's SQL-backed form — overdue
rows execute with re-arbitration before/alongside marking, candidates
stage at mark_end + window, counts exact relative to the schedule
(ADR-012 §6.7); the inline form preserved verbatim
- suite-column-sqlite: the first SQL-backed column, server-less —
form-independent reference rows mirror directly; the sweep rows are
schedule-relative (the recorded INV-4/5 mirror amendment)
- review-wave-3: the engine-wave gate (engine-vs-contract conformance)
Verification: dependency graph validated (all ids resolve, no cycles,
topological order clean); docs-only change.
Refs: docs/plans/implementation.md §Wave 3
glm-5.3-flash