diff --git a/src/test/kotlin/kestrel/ReplDiskTest.kt b/src/test/kotlin/kestrel/ReplDiskTest.kt
new file mode 100644
index 0000000..1a0d560
--- /dev/null
+++ b/src/test/kotlin/kestrel/ReplDiskTest.kt
@@ -0,0 +1,159 @@
+package kestrel
+
+import java.io.File
+import java.nio.file.Files
+import kestrel.cli.Repl
+import kestrel.persistence.Persistence
+import kestrel.store.sql.DiskCatalog
+import kotlin.test.Test
+import kotlin.test.assertContains
+import kotlin.test.assertFailsWith
+import kotlin.test.assertTrue
+
+/**
+ * [Repl] wired to the real disk-backed [DiskCatalog]/[kestrel.store.sql.DiskExecutor] pair instead
+ * of the in-memory [kestrel.catalog.Catalog]/[kestrel.engine.Executor] - the disk engine had been
+ * fully built out (B+Tree/pager/WAL/2PL, DDL, DML, transactions, EXPLAIN) across many prior sessions
+ * but was never reachable from the actual user-facing CLI, only from tests calling it directly. This
+ * file is the end-to-end proof that a SQL session typed at the REPL really persists through the disk
+ * engine, not just that the disk engine works in isolation.
+ */
+class ReplDiskTest {
+    private fun tempFile(prefix: String): File = Files.createTempFile(prefix, ".db").toFile().also { it.deleteOnExit() }
+
+    private fun runOnDisk(dataFile: File, walFile: File, script: String): String {
+        val output = StringBuilder()
+        val catalog = DiskCatalog.open(dataFile, walFile)
+        Repl(output, output, diskCatalog = catalog).run(script.reader().buffered())
+        return output.toString()
+    }
+
+    @Test
+    fun gateScenarioRendersOrderedResultThroughTheDiskBackedExecutor() {
+        val output = runOnDisk(
+            tempFile("kestrel-repl-data"),
+            tempFile("kestrel-repl-wal"),
+            """
+            CREATE TABLE users (id INTEGER PRIMARY KEY, name TEXT NOT NULL, age INTEGER);
+            INSERT INTO users VALUES (1, 'ada', 36), (2, 'linus', 54), (3, 'grace', 85);
+            SELECT name, age FROM users WHERE age > 40 ORDER BY age DESC;
+            .exit
+            """.trimIndent()
+        )
+        assertContains(output, "3 rows inserted")
+        assertContains(output, "grace")
+        assertContains(output, "linus")
+        assertTrue(output.indexOf("grace") < output.indexOf("linus"), "grace should be listed before linus")
+    }
+
+    @Test
+    fun metaCommandsReflectDiskCatalogStateForEveryObjectKind() {
+        val output = runOnDisk(
+            tempFile("kestrel-repl-data"),
+            tempFile("kestrel-repl-wal"),
+            """
+            CREATE TABLE users (id INTEGER PRIMARY KEY, email TEXT NOT NULL);
+            CREATE UNIQUE INDEX idx_email ON users (email);
+            CREATE VIEW active_users AS SELECT id FROM users;
+            CREATE SEQUENCE user_ids;
+            CREATE TRIGGER log_insert AFTER INSERT ON users FOR EACH ROW BEGIN DELETE FROM users WHERE 1 = 0; END;
+            .tables
+            .indexes
+            .views
+            .triggers
+            .sequences
+            .exit
+            """.trimIndent()
+        )
+        assertTrue(!output.contains("Error:"), output)
+        assertContains(output, "users")
+        assertContains(output, "idx_email")
+        assertContains(output, "active_users")
+        assertContains(output, "log_insert")
+        assertContains(output, "user_ids")
+    }
+
+    @Test
+    fun schemaPrintsColumnsForeignKeyCheckUniqueAndSecondaryIndexFromTheDiskCatalog() {
+        val output = runOnDisk(
+            tempFile("kestrel-repl-data"),
+            tempFile("kestrel-repl-wal"),
+            """
+            CREATE TABLE accounts (id INTEGER PRIMARY KEY, balance INTEGER NOT NULL CHECK (balance >= 0));
+            CREATE TABLE orders (
+              id INTEGER PRIMARY KEY,
+              account_id INTEGER,
+              code TEXT,
+              UNIQUE (code),
+              FOREIGN KEY (account_id) REFERENCES accounts (id)
+            );
+            CREATE INDEX idx_orders_code ON orders (code);
+            .schema orders
+            .exit
+            """.trimIndent()
+        )
+        assertContains(output, "CREATE TABLE orders")
+        assertContains(output, "id INTEGER PRIMARY KEY")
+        assertContains(output, "FOREIGN KEY (account_id) REFERENCES accounts (id)")
+        assertContains(output, "UNIQUE (code)")
+        assertContains(output, "CREATE INDEX idx_orders_code ON orders (code);")
+    }
+
+    @Test
+    fun dataSchemaAndIndexesSurviveClosingAndReopeningTheDiskCatalog() {
+        val dataFile = tempFile("kestrel-repl-data")
+        val walFile = tempFile("kestrel-repl-wal")
+        runOnDisk(
+            dataFile,
+            walFile,
+            """
+            CREATE TABLE users (id INTEGER PRIMARY KEY, name TEXT NOT NULL);
+            CREATE UNIQUE INDEX idx_name ON users (name);
+            INSERT INTO users VALUES (1, 'ada'), (2, 'grace');
+            .exit
+            """.trimIndent()
+        )
+        val reopened = runOnDisk(
+            dataFile,
+            walFile,
+            "SELECT name FROM users ORDER BY id ASC;\n.indexes\nINSERT INTO users VALUES (3, 'ada');\n.exit\n"
+        )
+        assertContains(reopened, "ada")
+        assertContains(reopened, "grace")
+        assertContains(reopened, "idx_name")
+        assertContains(
+            reopened,
+            "Error:",
+            message = "the UNIQUE index on name must still reject a duplicate name (new id, old name) after reopen"
+        )
+    }
+
+    @Test
+    fun explicitTransactionLeftOpenAtReplExitIsRolledBackNotSilentlyLost() {
+        val dataFile = tempFile("kestrel-repl-data")
+        val walFile = tempFile("kestrel-repl-wal")
+        runOnDisk(
+            dataFile,
+            walFile,
+            """
+            CREATE TABLE t (id INTEGER PRIMARY KEY);
+            INSERT INTO t VALUES (1);
+            BEGIN;
+            INSERT INTO t VALUES (2);
+            .exit
+            """.trimIndent()
+        )
+        val reopened = runOnDisk(dataFile, walFile, "SELECT id FROM t ORDER BY id ASC;\n.exit\n")
+        assertContains(reopened, "1")
+        assertTrue(!reopened.contains("2"), "the uncommitted INSERT inside BEGIN must not survive the abandoned transaction")
+    }
+
+    @Test
+    fun replRejectsCombiningTextBasedPersistenceWithTheDiskBackedCatalog() {
+        val persistenceDir = Files.createTempDirectory("kestrel-repl-persist").toFile().also { it.deleteOnExit() }
+        val catalog = DiskCatalog.open(tempFile("kestrel-repl-data"), tempFile("kestrel-repl-wal"))
+        assertFailsWith<IllegalArgumentException> {
+            Repl(persistence = Persistence(persistenceDir), diskCatalog = catalog)
+        }
+    }
+}