diff --git a/packages/backend-test-utils/src/cache/TestCaches.ts b/packages/backend-test-utils/src/cache/TestCaches.ts
index d4553697bf..27c07daa32 100644
--- a/packages/backend-test-utils/src/cache/TestCaches.ts
+++ b/packages/backend-test-utils/src/cache/TestCaches.ts
@@ -108,6 +108,9 @@ export class TestCaches {
   }
 
   eachSupportedId(): [TestCacheId][] {
+    if (this.supportedIds.length === 0) {
+      return [['MISSING' as TestCacheId]];
+    }
     return this.supportedIds.map(id => [id]);
   }
 
diff --git a/packages/backend-test-utils/src/database/TestDatabases.ts b/packages/backend-test-utils/src/database/TestDatabases.ts
index 8baac04193..46d966b6ee 100644
--- a/packages/backend-test-utils/src/database/TestDatabases.ts
+++ b/packages/backend-test-utils/src/database/TestDatabases.ts
@@ -124,6 +124,13 @@ export class TestDatabases {
   }
 
   eachSupportedId(): [TestDatabaseId][] {
+    if (this.supportedIds.length === 0) {
+      // Return a placeholder so that describe.each/it.each does not throw
+      // when no databases are available. The init() call will throw for
+      // the unknown ID, causing the test to be reported as failed rather
+      // than crashing the entire suite.
+      return [['MISSING' as TestDatabaseId]];
+    }
     return this.supportedIds.map(id => [id]);
   }