diff --git a/tests/corpus/consumer_sqe_test.rs b/tests/corpus/consumer_sqe_test.rs
new file mode 100644
index 00000000..503285cb
--- /dev/null
+++ b/tests/corpus/consumer_sqe_test.rs
@@ -0,0 +1,383 @@
+// Copyright 2026 Schuberg Philis
+// SPDX-License-Identifier: Apache-2.0
+//! SQE's catalog as a consumer fixture family (spec 013 Requirement 6).
+//!
+//! Req 6 says acceptance for the embedding API is spec 004's harness, not
+//! a new one: "a consumer statement set becomes a fixture family, diffed
+//! against pinned `sqlite3`... The first family is *SQE*'s catalog". This
+//! is that family.
+//!
+//! It lives here rather than in `tests/spike/014_embedding_api/` on
+//! purpose. ADR-0008: spike code is disposed, the evidence survives and
+//! "test material is committed as acceptance corpus for the real
+//! implementation — the ratchet". Spikes also do not run in CI
+//! (`make test-spikes` lists 001-009 and `ci.yml` mentions none), so a
+//! regression guard kept there would rot unnoticed.
+//!
+//! `catalog.sql` is SQE's schema **as it is today**: a plain table plus a
+//! named `CREATE UNIQUE INDEX`, not a declared composite `PRIMARY KEY`.
+//! That is not a simplification for the test — it is the workaround spec
+//! 013 records SQE having adopted, and the reason is #687: a table *this
+//! crate creates* with a declared composite PK gets no
+//! `sqlite_autoindex_*`, and the oracle then calls the file
+//! `database disk image is malformed` immediately, before any write.
+//! `catalog_declared_pk.sql` is the schema SQE wants back, pinned as
+//! #687's ratchet.
+//!
+//! Four things SQE needs are known-broken and pinned as `#[ignore]` with
+//! the ticket that flips them, the same shape as `tests/tiers/`. Each is
+//! written to pass once fixed, so closing a ticket un-ignores a test
+//! rather than needing one authored:
+//!
+//! - `catalog_ddl_is_idempotent` — #697
+//! - `a_column_named_key_is_usable` — #696
+//! - `catalog_sql_file_runs_verbatim` — #698
+//! - `declared_composite_pk_creates_a_valid_file` — #687
+
+#![allow(
+    clippy::unwrap_used,
+    clippy::expect_used,
+    clippy::panic,
+    clippy::indexing_slicing
+)]
+
+use std::path::{Path, PathBuf};
+use std::process::Command;
+
+use crate::oracle::{pinned_oracle, skip_no_oracle};
+
+fn fixture(name: &str) -> PathBuf {
+    Path::new(env!("CARGO_MANIFEST_DIR"))
+        .join("tests/corpus/fixtures/consumers/sqe")
+        .join(name)
+}
+
+fn catalog_path() -> PathBuf {
+    fixture("catalog.sql")
+}
+
+fn catalog_sql() -> String {
+    std::fs::read_to_string(catalog_path()).expect("catalog.sql")
+}
+
+/// The same SQL with `--` comment lines removed.
+///
+/// Needed because a statement beginning with a comment is a parse error
+/// here and is accepted by the oracle (#698) — the fixture's own header
+/// is enough to trip it. The oracle is always fed the file verbatim; only
+/// our side gets the stripped form, and `catalog_sql_file_runs_verbatim`
+/// pins the real behaviour so this crutch disappears when #698 closes.
+fn catalog_sql_without_comments() -> String {
+    catalog_sql()
+        .lines()
+        .filter(|l| !l.trim_start().starts_with("--"))
+        .collect::<Vec<_>>()
+        .join("\n")
+}
+
+fn workdir(tag: &str) -> PathBuf {
+    let dir = std::env::temp_dir().join(format!("sqlite-rs-sqe-{tag}-{}", std::process::id()));
+    std::fs::remove_dir_all(&dir).ok();
+    std::fs::create_dir_all(&dir).unwrap();
+    dir
+}
+
+/// The `sqlite-rs` binary under test. Built by `cargo test` because the
+/// corpus target depends on it being present; `env!("CARGO_BIN_EXE_...")`
+/// is not available to a `test = false` target, so resolve it next to the
+/// test executable.
+fn cli() -> PathBuf {
+    let mut p = std::env::current_exe().expect("test exe path");
+    p.pop();
+    if p.ends_with("deps") {
+        p.pop();
+    }
+    p.join("sqlite-rs")
+}
+
+/// Feeds the oracle over **stdin**, not `argv`. A leading `--` in an
+/// argument is read as a CLI option by `sqlite3` (and by us), so the
+/// fixture's header comment would otherwise be a spurious failure that
+/// says nothing about SQL.
+fn oracle_script(bin: &Path, db: &Path, sql: &str) -> String {
+    use std::io::Write;
+    use std::process::Stdio;
+    let mut child = Command::new(bin)
+        .arg(db)
+        .stdin(Stdio::piped())
+        .stdout(Stdio::piped())
+        .stderr(Stdio::piped())
+        .spawn()
+        .unwrap();
+    child
+        .stdin
+        .as_mut()
+        .unwrap()
+        .write_all(sql.as_bytes())
+        .unwrap();
+    let out = child.wait_with_output().unwrap();
+    assert!(
+        out.status.success(),
+        "oracle rejected the script: {}",
+        String::from_utf8_lossy(&out.stderr)
+    );
+    String::from_utf8_lossy(&out.stdout).trim_end().to_string()
+}
+
+fn oracle_run(bin: &Path, db: &Path, sql: &str) -> String {
+    let out = Command::new(bin).arg(db).arg(sql).output().unwrap();
+    assert!(
+        out.status.success(),
+        "oracle rejected {sql}: {}",
+        String::from_utf8_lossy(&out.stderr)
+    );
+    String::from_utf8_lossy(&out.stdout).trim_end().to_string()
+}
+
+fn ours_query(db: &Path, sql: &str) -> String {
+    let out = Command::new(cli())
+        .arg("query")
+        .arg(db)
+        .arg(sql)
+        .output()
+        .unwrap();
+    assert!(
+        out.status.success(),
+        "sqlite-rs rejected {sql}: {}",
+        String::from_utf8_lossy(&out.stderr)
+    );
+    String::from_utf8_lossy(&out.stdout).trim_end().to_string()
+}
+
+fn ours_exec(db: &Path, sql: &str) {
+    let out = Command::new(cli())
+        .arg("exec")
+        .arg(db)
+        .arg(sql)
+        .output()
+        .unwrap();
+    assert!(
+        out.status.success(),
+        "sqlite-rs rejected {sql}: {}",
+        String::from_utf8_lossy(&out.stderr)
+    );
+}
+
+/// The queries SQE issues against its catalog: existence probes with
+/// `LIMIT 1`, a namespace `UNION`, a point lookup on the composite key.
+const QUERIES: &[&str] = &[
+    "SELECT metadata_location FROM iceberg_tables WHERE catalog_name='cat' AND table_namespace='ns' AND table_name='t1' LIMIT 1",
+    "SELECT metadata_location FROM iceberg_tables WHERE catalog_name='cat' AND table_namespace='ns' AND table_name='absent' LIMIT 1",
+    "SELECT table_name FROM iceberg_tables WHERE catalog_name='cat' AND table_namespace='ns' ORDER BY table_name",
+    "SELECT namespace FROM iceberg_namespace_properties WHERE catalog_name='cat' UNION SELECT table_namespace FROM iceberg_tables WHERE catalog_name='cat' ORDER BY 1",
+    "SELECT property_value FROM iceberg_namespace_properties WHERE catalog_name='cat' AND namespace='ns' AND property_key='owner' LIMIT 1",
+    "SELECT count(*) FROM iceberg_tables",
+    "SELECT count(*) FROM iceberg_namespace_properties",
+];
+
+/// Both engines build the catalog from the same `.sql`, then answer the
+/// same queries. This is the claim "sqlite-rs works for SQE's read path",
+/// stated as a diff rather than an assertion.
+#[test]
+fn catalog_queries_match_the_oracle() {
+    let Some(bin) = pinned_oracle() else {
+        skip_no_oracle("catalog_queries_match_the_oracle");
+        return;
+    };
+    let dir = workdir("read");
+    let (theirs_db, ours_db) = (dir.join("o.db"), dir.join("m.db"));
+    oracle_script(&bin, &theirs_db, &catalog_sql());
+    for stmt in sqlite_rs::parser::split_statements(&catalog_sql_without_comments()) {
+        ours_exec(&ours_db, &stmt);
+    }
+
+    for q in QUERIES {
+        assert_eq!(
+            ours_query(&ours_db, q),
+            oracle_run(&bin, &theirs_db, q),
+            "diverged on {q}"
+        );
+    }
+    std::fs::remove_dir_all(&dir).ok();
+}
+
+/// SQE's write path: a conditional `UPDATE` swapping a metadata pointer
+/// (its optimistic-concurrency step), a `DELETE`, and the resulting file
+/// still being one the oracle will read.
+#[test]
+fn catalog_writes_match_the_oracle_and_leave_a_valid_file() {
+    let Some(bin) = pinned_oracle() else {
+        skip_no_oracle("catalog_writes_match_the_oracle_and_leave_a_valid_file");
+        return;
+    };
+    let dir = workdir("write");
+    let (theirs_db, ours_db) = (dir.join("o.db"), dir.join("m.db"));
+    oracle_script(&bin, &theirs_db, &catalog_sql());
+    for stmt in sqlite_rs::parser::split_statements(&catalog_sql_without_comments()) {
+        ours_exec(&ours_db, &stmt);
+    }
+
+    let writes = [
+        // The compare-and-swap SQE treats zero rows affected as a lost race.
+        "UPDATE iceberg_tables SET metadata_location='s3://bucket/t1/meta2.json' WHERE catalog_name='cat' AND table_namespace='ns' AND table_name='t1' AND metadata_location='s3://bucket/t1/meta.json'",
+        // The same statement again: now a no-op.
+        "UPDATE iceberg_tables SET metadata_location='s3://bucket/t1/meta3.json' WHERE catalog_name='cat' AND table_namespace='ns' AND table_name='t1' AND metadata_location='s3://bucket/t1/meta.json'",
+        "DELETE FROM iceberg_tables WHERE catalog_name='cat' AND table_namespace='other'",
+    ];
+    for w in writes {
+        oracle_run(&bin, &theirs_db, w);
+        ours_exec(&ours_db, w);
+    }
+
+    for q in [
+        "SELECT catalog_name, table_namespace, table_name, metadata_location FROM iceberg_tables ORDER BY table_name",
+        "SELECT count(*) FROM iceberg_tables",
+    ] {
+        assert_eq!(
+            ours_query(&ours_db, q),
+            oracle_run(&bin, &theirs_db, q),
+            "diverged on {q}"
+        );
+    }
+
+    // The file we wrote must be one stock SQLite considers sound — the
+    // check that caught #685 and #697.
+    assert_eq!(
+        oracle_run(&bin, &ours_db, "PRAGMA integrity_check;"),
+        "ok",
+        "our catalog file is not one the oracle will read"
+    );
+    std::fs::remove_dir_all(&dir).ok();
+}
+
+/// SQE runs its catalog DDL on **every** startup — that is what `IF NOT
+/// EXISTS` is for. Today the second run appends a duplicate
+/// `sqlite_master` row and leaks a root page, so the oracle calls the
+/// file malformed.
+#[test]
+#[ignore = "#697: CREATE TABLE IF NOT EXISTS ignores its guard, corrupting the file on the second run"]
+fn catalog_ddl_is_idempotent() {
+    let Some(bin) = pinned_oracle() else {
+        skip_no_oracle("catalog_ddl_is_idempotent");
+        return;
+    };
+    let dir = workdir("idem");
+    let ours_db = dir.join("m.db");
+    let sql = catalog_sql_without_comments();
+
+    for stmt in sqlite_rs::parser::split_statements(&sql) {
+        ours_exec(&ours_db, &stmt);
+    }
+    // Second startup: the DDL only, as SQE would issue it.
+    for stmt in sqlite_rs::parser::split_statements(&sql) {
+        if stmt.to_ascii_uppercase().starts_with("CREATE TABLE") {
+            ours_exec(&ours_db, &stmt);
+        }
+    }
+
+    assert_eq!(
+        oracle_run(
+            &bin,
+            &ours_db,
+            "SELECT count(*) FROM sqlite_master WHERE type='table' AND name='iceberg_tables';"
+        ),
+        "1",
+        "duplicate sqlite_master row after re-running IF NOT EXISTS"
+    );
+    assert_eq!(oracle_run(&bin, &ours_db, "PRAGMA integrity_check;"), "ok");
+    assert_eq!(
+        ours_query(&ours_db, "SELECT count(*) FROM iceberg_tables"),
+        "3",
+        "rows written before the second DDL run must survive it"
+    );
+    std::fs::remove_dir_all(&dir).ok();
+}
+
+/// `key` is one of 89 keywords we reserve that SQLite treats as an
+/// identifier. Whether SQE's namespace-properties table literally names a
+/// column `key` is Jacob's to confirm — but a consumer cannot be told to
+/// avoid `key`, so this is pinned regardless.
+#[test]
+#[ignore = "#696: 89 keywords are reserved that SQLite's parse.y %fallback treats as identifiers"]
+fn a_column_named_key_is_usable() {
+    let Some(bin) = pinned_oracle() else {
+        skip_no_oracle("a_column_named_key_is_usable");
+        return;
+    };
+    let dir = workdir("key");
+    let ours_db = dir.join("m.db");
+
+    ours_exec(
+        &ours_db,
+        "CREATE TABLE props (namespace TEXT, key TEXT, value TEXT, PRIMARY KEY (namespace, key))",
+    );
+    ours_exec(
+        &ours_db,
+        "INSERT INTO props VALUES ('ns','owner','data-eng')",
+    );
+    assert_eq!(
+        ours_query(&ours_db, "SELECT key, value FROM props"),
+        "owner|data-eng"
+    );
+    assert_eq!(oracle_run(&bin, &ours_db, "PRAGMA integrity_check;"), "ok");
+    std::fs::remove_dir_all(&dir).ok();
+}
+
+/// The fixture file, comments and all, run through this crate exactly as
+/// the oracle runs it. A consumer ships its schema as a commented `.sql`
+/// file; that has to work.
+#[test]
+#[ignore = "#698: a statement beginning with a SQL comment is a parse error"]
+fn catalog_sql_file_runs_verbatim() {
+    let dir = workdir("verbatim");
+    let ours_db = dir.join("m.db");
+    for stmt in sqlite_rs::parser::split_statements(&catalog_sql()) {
+        ours_exec(&ours_db, &stmt);
+    }
+    assert_eq!(
+        ours_query(&ours_db, "SELECT count(*) FROM iceberg_tables"),
+        "3"
+    );
+    std::fs::remove_dir_all(&dir).ok();
+}
+
+/// The schema SQE actually wants: a declared composite `PRIMARY KEY`
+/// rather than a named unique index.
+///
+/// Blocked in the direction that matters most — a table *we* create is
+/// malformed to the oracle straight away, with no write involved, because
+/// no `sqlite_autoindex_*` is emitted. #685 fixed adopting a
+/// stock-created file; this is the same gap in the direction we control,
+/// and it is why SQE carries the named-index workaround at all.
+#[test]
+#[ignore = "#687: CREATE TABLE emits no sqlite_autoindex_* for a declared composite PRIMARY KEY"]
+fn declared_composite_pk_creates_a_valid_file() {
+    let Some(bin) = pinned_oracle() else {
+        skip_no_oracle("declared_composite_pk_creates_a_valid_file");
+        return;
+    };
+    let dir = workdir("declpk");
+    let ours_db = dir.join("m.db");
+    let sql = std::fs::read_to_string(fixture("catalog_declared_pk.sql")).unwrap();
+    for stmt in sqlite_rs::parser::split_statements(&sql) {
+        ours_exec(&ours_db, &stmt);
+    }
+
+    assert_eq!(
+        oracle_run(&bin, &ours_db, "PRAGMA integrity_check;"),
+        "ok",
+        "a file we created with a declared composite PK is not one the oracle will read"
+    );
+    // And the constraint it declares must actually be enforced.
+    let dup = Command::new(cli())
+        .arg("exec")
+        .arg(&ours_db)
+        .arg("INSERT INTO iceberg_tables VALUES ('cat','ns','t1','s3://elsewhere')")
+        .output()
+        .unwrap();
+    assert!(
+        !dup.status.success(),
+        "the declared composite PRIMARY KEY did not reject a duplicate"
+    );
+    std::fs::remove_dir_all(&dir).ok();
+}
diff --git a/tests/corpus/fixtures/consumers/sqe/catalog.sql b/tests/corpus/fixtures/consumers/sqe/catalog.sql
new file mode 100644
index 00000000..454dfdc9
--- /dev/null
+++ b/tests/corpus/fixtures/consumers/sqe/catalog.sql
@@ -0,0 +1,21 @@
+CREATE TABLE IF NOT EXISTS iceberg_tables (
+  catalog_name TEXT,
+  table_namespace TEXT,
+  table_name TEXT,
+  metadata_location TEXT
+);
+CREATE UNIQUE INDEX IF NOT EXISTS iceberg_tables_pk
+  ON iceberg_tables (catalog_name, table_namespace, table_name);
+CREATE TABLE IF NOT EXISTS iceberg_namespace_properties (
+  catalog_name TEXT,
+  namespace TEXT,
+  property_key TEXT,
+  property_value TEXT
+);
+CREATE UNIQUE INDEX IF NOT EXISTS iceberg_namespace_properties_pk
+  ON iceberg_namespace_properties (catalog_name, namespace, property_key);
+INSERT INTO iceberg_tables VALUES ('cat','ns','t1','s3://bucket/t1/meta.json');
+INSERT INTO iceberg_tables VALUES ('cat','ns','t2','s3://bucket/t2/meta.json');
+INSERT INTO iceberg_tables VALUES ('cat','other','t3','s3://bucket/t3/meta.json');
+INSERT INTO iceberg_namespace_properties VALUES ('cat','ns','owner','data-eng');
+INSERT INTO iceberg_namespace_properties VALUES ('cat','ns','location','s3://bucket/ns');
diff --git a/tests/corpus/fixtures/consumers/sqe/catalog_declared_pk.sql b/tests/corpus/fixtures/consumers/sqe/catalog_declared_pk.sql
new file mode 100644
index 00000000..2a4e1199
--- /dev/null
+++ b/tests/corpus/fixtures/consumers/sqe/catalog_declared_pk.sql
@@ -0,0 +1,9 @@
+CREATE TABLE IF NOT EXISTS iceberg_tables (
+  catalog_name TEXT,
+  table_namespace TEXT,
+  table_name TEXT,
+  metadata_location TEXT,
+  PRIMARY KEY (catalog_name, table_namespace, table_name)
+);
+INSERT INTO iceberg_tables VALUES ('cat','ns','t1','s3://bucket/t1/meta.json');
+INSERT INTO iceberg_tables VALUES ('cat','ns','t2','s3://bucket/t2/meta.json');
diff --git a/tests/corpus/main.rs b/tests/corpus/main.rs
index e0a60865..d486c5f5 100644
--- a/tests/corpus/main.rs
+++ b/tests/corpus/main.rs
@@ -13,6 +13,7 @@
     clippy::arithmetic_side_effects
 )]
 
+mod consumer_sqe_test;
 mod harness;
 mod oracle;