frontend parity: Gremlin and SQL meet at the same Quack Query (test-only witness + parity matrix)

.claude/board/AGENT_LOG.md

@@ -1,3 +1,9 @@
+## 2026-10-03 — Explore agent: SurrealQL AST harvest (D-FPW-0)
+
+- Read-only map of `/home/user/surrealdb` parser/AST: `Part::Graph(Lookup)` per hop, `Dir::{In,Out,Both}`, edge tables with `in`/`out`, bag flatten at `val/value/get.rs:499`, `Recurse`/`RecurseInstruction`.
+- Constraints: `sql::*` is `pub(crate)`; public arena AST unpublished; BSL 1.1.
+- Three claims re-read by the orchestrator. Folded into plan §5. No commit of its own.
+
 ## 2026-09-30 — 5+3 council on `deepnsm-v2-lexical-address-v1` (PR #1307)
 
 - The 5: prior-art, iron-rule, code truth, cascade-impact, creative-explorer.

.claude/board/INTEGRATION_PLANS.md

@@ -1,3 +1,12 @@
+## 2026-10-03 — frontend-parity-witness-v1 — SQL, Cypher, Gremlin, SurrealQL on one population algebra → `.claude/plans/frontend-parity-witness-v1.md`
+
+**Status:** MEASURED for SQL ↔ Gremlin (test-only witness in `lance-graph-quack/tests/gremlin_parity.rs`); analysis for Cypher (#1306 plan) and SurrealQL (AST). D-FPW-0..4. No production code.
+
+- Gremlin and SQL meet at the same `Query` value; execution equals DuckDB and a bulk oracle.
+- Anchor rule: functional hop keeps the anchor; one fan-out re-anchors on the path population.
+- Five gaps pass the two-witness rule; the two that decide traversal are #1308 (a) and (b)/(d).
+- Input for #1306 D-CML-2: RF-BAG is broader than the semantics require.
+
 ## 2026-09-30 (2) — deepnsm-v2-lexical-address-v1 — a word is a 16-bit address into a versioned, baked COCA codebook → `.claude/plans/deepnsm-v2-lexical-address-v1.md`
 
 **Status:** PROPOSAL (D-LXA-1..4), ratified v3 by a 5+3 council. No code authorized.

.claude/board/STATUS_BOARD.md

@@ -1,3 +1,15 @@
+## D-FPW — Frontend parity witness (2026-10-03)
+
+Plan: `.claude/plans/frontend-parity-witness-v1.md`. Entry: `entries/2026-10-03-frontend-parity-witness.md`.
+
+| D-id | scope | status | gate / falsifier |
+|---|---|---|---|
+| **D-FPW-0** | inventory + parity matrix (SQL/Quack, Cypher #1306, Gremlin, SurrealQL) | Shipped | plan §1, §4 |
+| **D-FPW-1** | Gremlin witness: typed steps → `quack::Query`, 13 tests | Shipped | `Query ==` SQL shape; DuckDB answers; bulk oracle; 5 disable runs red |
+| **D-FPW-2** | feed the anchor rule (functional hop ⇒ exact bag count) into #1306 D-CML-2 | Queued | a Cypher `count(*)` after a functional hop matches the oracle |
+| **D-FPW-3** | SurrealQL fork-side lowering hook (`sql::Lookup` → `Query`) | Queued | operator: BSL 1.1 licensing first |
+| **D-FPW-4** | gap G4 (sum of a foreign value) checked against `GroupReduce` before being called a primitive | Queued | — |
+
 ## D-LXC — DeepNSM-v2 lexical-evidence consumer + candidate next parts (2026-09-29)
 
 Plan: `.claude/plans/deepnsm-v2-lexical-evidence-consumer-v1.md`. Convergence brief: `.claude/prompts/deepnsm-v2-lexical-consumer-converge.md`.

.claude/board/entries/2026-10-03-frontend-parity-witness.md

@@ -0,0 +1,26 @@
+# Frontend parity witness: Gremlin and SQL meet at the same Quack `Query` (2026-10-03)
+
+**Status:** MEASURED (SQL ↔ Gremlin); ANALYSIS (Cypher against the #1306 plan,
+SurrealQL against its AST). Plan: `.claude/plans/frontend-parity-witness-v1.md`.
+Code: `crates/lance-graph-quack/tests/gremlin_parity.rs` (test-only, 13 tests).
+
+- A typed Gremlin step vocabulary lowers onto `lance_graph_quack::Query` through a
+  test-only adapter. For the shapes that lower, the Gremlin `Query` is `==` the
+  SQL-shaped `Query`, and execution equals DuckDB's committed answers
+  (`join_sum_country` 1237848, `join_group_count_country`,
+  `join_count_docs_with_posted` 511 via the oracle) and an independent
+  row-at-a-time bulk oracle.
+- **Anchor rule:** a functional hop keeps the anchor (fk reads); one fan-out
+  re-anchors on the table whose rows are the paths (child or edge table). One M:N
+  hop is therefore one `Program` over the edge population, with exact bag counts.
+- **Input for #1306 D-CML-2:** RF-BAG refuses any non-DISTINCT count after a hop.
+  After a functional hop, or one hop over an edge population, the bag count is
+  exact (anchor rows = paths). RF-BAG is broader than the semantics require.
+- **Gaps passing the two-witness rule** (none built): composed functional read
+  (= #1308 (a)); barrier + workspace after a fan-out (= #1308 (b)/(d), #1310);
+  ordered compare through an fk; sum of a foreign value; ordered compare on `u32`.
+- **SurrealQL:** a hop is `Part::Graph(Lookup)`, a per-hop mini-SELECT over a
+  first-class edge table (`in`/`out`), bag-flattened. Structurally the same as the
+  edge-population re-anchor. Not reusable as a dependency: `sql::*` is
+  `pub(crate)`, the public arena AST is unpublished, license is BSL 1.1.
+- DuckGQL / DuckPG: no code or plan by those names in the tree.

.claude/board/entries/README.md

@@ -25,11 +25,12 @@ index row, (3) no duplicate entry id. Checks 1 and 2 are deliberately
 opposite directions; the stranding this convention prevents shows up in
 exactly one of them, never both.
 
-182 entries, 2026-08-06 .. 2026-10-03.
+183 entries, 2026-08-06 .. 2026-10-03.
 
 | date | entry id | finding | file |
 |---|---|---|---|
 | 2026-10-03 | `known-is-not-alpha-premise-gate` |  | [2026-10-03-known-is-not-alpha-premise-gate.md](2026-10-03-known-is-not-alpha-premise-gate.md) |
+| 2026-10-03 | `frontend-parity-witness` |  | [2026-10-03-frontend-parity-witness.md](2026-10-03-frontend-parity-witness.md) |
 | 2026-10-03 | `dir-sim-soa-quack` | Directory simulation on SoA + Quack: one-edge mutation 853 B at 1k and 100k users | [2026-10-03-dir-sim-soa-quack.md](2026-10-03-dir-sim-soa-quack.md) |
 | 2026-10-03 | `coresearch-chained-hop` |  | [2026-10-03-coresearch-chained-hop.md](2026-10-03-coresearch-chained-hop.md) |
 | 2026-09-30 | `three-reference-sets-are-not-ordinal-aligned` |  | [2026-09-30-three-reference-sets-are-not-ordinal-aligned.md](2026-09-30-three-reference-sets-are-not-ordinal-aligned.md) |