diff --git a/rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/.gitignore b/rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/.gitignore
new file mode 100644
index 00000000000..3b4d77eb40d
--- /dev/null
+++ b/rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/.gitignore
@@ -0,0 +1,3 @@
+*.testproj/
+*.actual
+*.log
diff --git a/rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/README.md b/rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/README.md
new file mode 100644
index 00000000000..0acd82f4b42
--- /dev/null
+++ b/rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/README.md
@@ -0,0 +1,35 @@
+# Rust upgrade preservation test
+
+This directory contains a manual regression test for the Rust dbscheme upgrade from rust-analyzer 0.0.301 to 0.0.328.
+
+It is **not yet checked by CI**. The test has to be run manually because it requires building an old extractor to create an old-schema database first.
+
+## Directory structure
+
+- `old/`: Test query for the **old** schema, showing fields that will be upgraded
+- `new/`: Test query and sources for the **new** schema after upgrade
+
+## Running the test
+
+From anywhere in the repository:
+
+```bash
+rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/run-test.sh
+```
+
+Or override the old commit if needed:
+
+```bash
+OLD_COMMIT=<commit> rust/ql/lib/upgrades/.../test/run-test.sh
+```
+
+The script will:
+1. Copy test files to a temp directory
+2. Stash uncommitted changes and checkout the old commit
+3. Build the old extractor with `bazel run //rust:install`
+4. Create an old-schema database with `codeql test run`
+5. Restore your branch and pop the stash
+6. Upgrade the database to the new schema
+7. Run the preservation test on the upgraded database
+
+If the expected output needs to be refreshed after an intentional query change, manually run the final `codeql test run` with `--learn`.
diff --git a/rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/new/UpgradeShapes.expected b/rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/new/UpgradeShapes.expected
new file mode 100644
index 00000000000..6adf4a878be
--- /dev/null
+++ b/rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/new/UpgradeShapes.expected
@@ -0,0 +1,20 @@
+formatArgNamePreserved
+| upgrade_shapes.rs:22:37:22:41 | FormatArgsArg | upgrade_shapes.rs:22:37:22:37 | FormatArgsArgName | upgrade_shapes.rs:22:41:22:41 | 1 | 37 | 1 |
+| upgrade_shapes.rs:22:44:22:48 | FormatArgsArg | upgrade_shapes.rs:22:44:22:44 | FormatArgsArgName | upgrade_shapes.rs:22:48:22:48 | 2 | 44 | 2 |
+tryBlockModifierPreserved
+| upgrade_shapes.rs:21:13:21:21 | { ... } | upgrade_shapes.rs:21:13:21:21 | TryBlockModifier |
+structFieldDefaultPreserved
+| upgrade_shapes.rs:9:5:9:17 | field: u8 | upgrade_shapes.rs:9:17:9:17 | ConstArg | upgrade_shapes.rs:9:17:9:17 | 1 |
+variantDiscriminantPreserved
+| upgrade_shapes.rs:13:5:13:9 | V | upgrade_shapes.rs:13:9:13:9 | ConstArg | upgrade_shapes.rs:13:9:13:9 | 2 |
+pathMetaPreserved
+| upgrade_shapes.rs:4:3:4:11 | PathMeta | path_meta |
+| upgrade_shapes.rs:7:3:7:19 | PathMeta | path_meta |
+keyValueMetaPreserved
+| upgrade_shapes.rs:5:3:5:15 | KeyValueMeta | key_value | upgrade_shapes.rs:5:15:5:15 | 1 |
+tokenTreeMetaPreserved
+| upgrade_shapes.rs:6:3:6:18 | TokenTreeMeta | token_tree | upgrade_shapes.rs:6:13:6:18 | TokenTree |
+unsafeMetaPreserved
+| upgrade_shapes.rs:7:3:7:19 | UnsafeMeta | upgrade_shapes.rs:7:3:7:19 | PathMeta | path_meta |
+traitAliasPreserved
+| upgrade_shapes.rs:16:1:18:12 | trait Alias | upgrade_shapes.rs:16:7:16:11 | Alias | upgrade_shapes.rs:16:18:16:22 | ... | upgrade_shapes.rs:17:1:18:11 | WhereClause |
diff --git a/rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/new/UpgradeShapes.ql b/rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/new/UpgradeShapes.ql
new file mode 100644
index 00000000000..bd983a8290c
--- /dev/null
+++ b/rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/new/UpgradeShapes.ql
@@ -0,0 +1,73 @@
+import codeql.rust.elements
+
+private predicate inUpgradeShapesFile(Locatable loc) {
+  loc.getFile().getBaseName() = "upgrade_shapes.rs"
+}
+
+query predicate formatArgNamePreserved(
+  FormatArgsArg arg, FormatArgsArgName argName, Expr expr, int argNameColumn, string exprText
+) {
+  inUpgradeShapesFile(arg) and
+  argName = arg.getArgName() and
+  expr = arg.getExpr() and
+  argNameColumn = argName.getLocation().getStartColumn() and
+  exprText = expr.toString()
+}
+
+query predicate tryBlockModifierPreserved(BlockExpr block, TryBlockModifier modifier) {
+  inUpgradeShapesFile(block) and
+  modifier = block.getTryBlockModifier() and
+  modifier.isTry() and
+  not modifier.hasTypeRepr()
+}
+
+query predicate structFieldDefaultPreserved(StructField field, ConstArg defaultVal, Expr expr) {
+  inUpgradeShapesFile(field) and
+  defaultVal = field.getDefaultVal() and
+  expr = defaultVal.getExpr()
+}
+
+query predicate variantDiscriminantPreserved(Variant variant, ConstArg constArg, Expr expr) {
+  inUpgradeShapesFile(variant) and
+  constArg = variant.getConstArg() and
+  expr = constArg.getExpr()
+}
+
+query predicate pathMetaPreserved(PathMeta meta, string pathText) {
+  inUpgradeShapesFile(meta) and
+  pathText = meta.getPath().getText() and
+  pathText = "path_meta"
+}
+
+query predicate keyValueMetaPreserved(KeyValueMeta meta, string pathText, Expr expr) {
+  inUpgradeShapesFile(meta) and
+  pathText = meta.getPath().getText() and
+  pathText = "key_value" and
+  expr = meta.getExpr()
+}
+
+query predicate tokenTreeMetaPreserved(TokenTreeMeta meta, string pathText, TokenTree tokenTree) {
+  inUpgradeShapesFile(meta) and
+  pathText = meta.getPath().getText() and
+  pathText = "token_tree" and
+  tokenTree = meta.getTokenTree()
+}
+
+query predicate unsafeMetaPreserved(UnsafeMeta meta, PathMeta inner, string pathText) {
+  inUpgradeShapesFile(meta) and
+  meta.isUnsafe() and
+  inner = meta.getMeta() and
+  pathText = inner.getPath().getText() and
+  pathText = "path_meta"
+}
+
+query predicate traitAliasPreserved(
+  Trait trait, Name name, TypeBoundList bounds, WhereClause whereClause
+) {
+  inUpgradeShapesFile(trait) and
+  name = trait.getName() and
+  name.getText() = "Alias" and
+  bounds = trait.getTypeBoundList() and
+  whereClause = trait.getWhereClause() and
+  not trait.hasAssocItemList()
+}
diff --git a/rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/new/qlpack.yml b/rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/new/qlpack.yml
new file mode 100644
index 00000000000..81a7b0a2503
--- /dev/null
+++ b/rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/new/qlpack.yml
@@ -0,0 +1,6 @@
+name: codeql/rust-upgrade-66a489863649185f4a9770f894505803059a1312-test-new
+version: 0.0.0
+dependencies:
+  codeql/rust-all: ${workspace}
+extractor: rust
+tests: .
diff --git a/rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/new/upgrade_shapes.rs b/rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/new/upgrade_shapes.rs
new file mode 100644
index 00000000000..e64d8f6582c
--- /dev/null
+++ b/rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/new/upgrade_shapes.rs
@@ -0,0 +1,23 @@
+#![allow(dead_code)]
+#![feature(more_qualified_paths)]
+
+#[path_meta]
+#[key_value = 1]
+#[token_tree(list)]
+#[unsafe(path_meta)]
+struct S {
+    field: u8 = 1,
+}
+
+enum E {
+    V = 2,
+}
+
+trait Alias<T> = Clone
+where
+    T: Copy;
+
+fn f() {
+    let _ = try { 1 };
+    let _ = format_args!("{b} {a}", a = 1, b = 2);
+}
diff --git a/rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/old/OldShapes.expected b/rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/old/OldShapes.expected
new file mode 100644
index 00000000000..8cb5c2511a4
--- /dev/null
+++ b/rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/old/OldShapes.expected
@@ -0,0 +1,22 @@
+formatArgsArgName
+| upgrade_shapes.rs:22:31:22:31 | a | upgrade_shapes.rs:22:35:22:35 | 1 | a |
+| upgrade_shapes.rs:22:38:22:38 | b | upgrade_shapes.rs:22:42:22:42 | 2 | b |
+metaExpr
+| upgrade_shapes.rs:5:1:5:15 | #[key_value = 1] | upgrade_shapes.rs:5:15:5:15 | 1 |
+metaIsUnsafe
+| upgrade_shapes.rs:7:1:7:21 | #[unsafe(path_meta)] | 
+metaPath
+| upgrade_shapes.rs:4:1:4:12 | #[path_meta] | path_meta |
+| upgrade_shapes.rs:5:1:5:15 | #[key_value = 1] | key_value |
+| upgrade_shapes.rs:6:1:6:19 | #[token_tree(list)] | token_tree |
+| upgrade_shapes.rs:7:1:7:21 | #[unsafe(path_meta)] | path_meta |
+metaTokenTree
+| upgrade_shapes.rs:6:1:6:19 | #[token_tree(list)] | upgrade_shapes.rs:6:13:6:18 | (list) |
+structFieldDefault
+| upgrade_shapes.rs:9:5:9:17 | field: u8 = 1 | upgrade_shapes.rs:9:17:9:17 | 1 |
+traitAlias
+| upgrade_shapes.rs:16:1:18:12 | TraitAlias | Alias | upgrade_shapes.rs:16:18:16:23 | = Clone | upgrade_shapes.rs:17:1:18:12 | where... |
+tryBlock
+| upgrade_shapes.rs:21:13:21:23 | try { 1 } |
+variantDiscriminant
+| upgrade_shapes.rs:13:5:13:9 | V = 2 | upgrade_shapes.rs:13:9:13:9 | 2 |
diff --git a/rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/old/OldShapes.ql b/rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/old/OldShapes.ql
new file mode 100644
index 00000000000..ced2690b7db
--- /dev/null
+++ b/rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/old/OldShapes.ql
@@ -0,0 +1,56 @@
+import codeql.rust.elements
+
+private predicate inUpgradeShapesFile(Locatable loc) {
+  loc.getFile().getBaseName() = "upgrade_shapes.rs"
+}
+
+query predicate formatArgsArgName(FormatArgsArg arg, Name argName, Expr expr, string nameText) {
+  inUpgradeShapesFile(arg) and
+  argName = arg.getName() and
+  expr = arg.getExpr() and
+  nameText = argName.getText()
+}
+
+query predicate tryBlock(BlockExpr block) {
+  inUpgradeShapesFile(block) and
+  block.isTry()
+}
+
+query predicate structFieldDefault(StructField field, Expr defaultVal) {
+  inUpgradeShapesFile(field) and
+  defaultVal = field.getDefault()
+}
+
+query predicate variantDiscriminant(Variant variant, Expr discriminant) {
+  inUpgradeShapesFile(variant) and
+  discriminant = variant.getDiscriminant()
+}
+
+query predicate metaPath(Meta meta, string pathText) {
+  inUpgradeShapesFile(meta) and
+  pathText = meta.getPath().getText()
+}
+
+query predicate metaExpr(Meta meta, Expr expr) {
+  inUpgradeShapesFile(meta) and
+  expr = meta.getExpr()
+}
+
+query predicate metaTokenTree(Meta meta, TokenTree tokenTree) {
+  inUpgradeShapesFile(meta) and
+  tokenTree = meta.getTokenTree()
+}
+
+query predicate metaIsUnsafe(Meta meta) {
+  inUpgradeShapesFile(meta) and
+  meta.isUnsafe()
+}
+
+query predicate traitAlias(
+  TraitAlias alias, Name name, TypeBoundList bounds, WhereClause whereClause
+) {
+  inUpgradeShapesFile(alias) and
+  name = alias.getName() and
+  bounds = alias.getTypeBoundList() and
+  whereClause = alias.getWhereClause()
+}
diff --git a/rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/run-test.sh b/rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/run-test.sh
new file mode 100755
index 00000000000..93e79ff4daa
--- /dev/null
+++ b/rust/ql/lib/upgrades/66a489863649185f4a9770f894505803059a1312/test/run-test.sh
@@ -0,0 +1,62 @@
+#!/usr/bin/env bash
+# Manual regression test for the Rust dbscheme upgrade from rust-analyzer 0.0.301 to 0.0.328.
+# See README.md for details.
+
+set -euo pipefail
+
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+REPO_ROOT="$(cd "$SCRIPT_DIR/../../../../.." && pwd)"
+OLD_COMMIT="${OLD_COMMIT:-491c373e076}"  # origin/main at time of this upgrade
+
+cd "$REPO_ROOT"
+
+echo "==> Setting up temp directory for old test..."
+OLD_TEST_TMP=$(mktemp -d)
+trap 'rm -rf "$OLD_TEST_TMP"' EXIT
+
+# Copy old test query and new test sources (qlpack, upgrade_shapes.rs) to temp
+cp "$SCRIPT_DIR/old/OldShapes.ql" "$SCRIPT_DIR/old/OldShapes.expected" "$OLD_TEST_TMP/"
+cp "$SCRIPT_DIR/new/qlpack.yml" "$SCRIPT_DIR/new/upgrade_shapes.rs" "$OLD_TEST_TMP/"
+
+echo "==> Stashing any uncommitted changes..."
+git stash --quiet || true
+
+restore_branch() {
+    echo "==> Restoring original branch..."
+    git checkout --quiet -
+    git stash pop --quiet 2>/dev/null || true
+}
+trap 'restore_branch; rm -rf "$OLD_TEST_TMP"' EXIT
+
+echo "==> Checking out old commit ($OLD_COMMIT)..."
+git checkout --quiet "$OLD_COMMIT"
+
+echo "==> Building old extractor (this may take a while)..."
+bazel run //rust:install
+
+echo "==> Creating old-schema test database..."
+rm -rf "$OLD_TEST_TMP"/*.testproj
+codeql test run \
+    --search-path . \
+    --keep-databases \
+    "$OLD_TEST_TMP/OldShapes.ql"
+
+echo "==> Copying dataset for upgrade..."
+cp -a "$OLD_TEST_TMP/test.testproj/db-rust" "$OLD_TEST_TMP/upgraded-dataset"
+
+restore_branch
+trap 'rm -rf "$OLD_TEST_TMP"' EXIT
+
+echo "==> Upgrading dataset to new schema..."
+codeql dataset upgrade "$OLD_TEST_TMP/upgraded-dataset" \
+    --search-path . \
+    --target-dbscheme rust/ql/lib/rust.dbscheme
+
+echo "==> Running preservation test on upgraded dataset..."
+codeql test run \
+    --search-path . \
+    --dataset="$OLD_TEST_TMP/upgraded-dataset" \
+    --check-databases \
+    "$SCRIPT_DIR/new/UpgradeShapes.ql"
+
+echo "==> All tests passed!"