diff --git a/source/src/main/java/one/nem/lacerta/source/database/entity/Document.java b/source/src/main/java/one/nem/lacerta/source/database/entity/Document.java
new file mode 100644
index 00000000..f11114b2
--- /dev/null
+++ b/source/src/main/java/one/nem/lacerta/source/database/entity/Document.java
@@ -0,0 +1,4 @@
+package one.nem.lacerta.source.database.entity;
+
+public class Document {
+}
diff --git a/source/src/main/java/one/nem/lacerta/source/database/entity/Library.java b/source/src/main/java/one/nem/lacerta/source/database/entity/Library.java
new file mode 100644
index 00000000..091087e4
--- /dev/null
+++ b/source/src/main/java/one/nem/lacerta/source/database/entity/Library.java
@@ -0,0 +1,4 @@
+package one.nem.lacerta.source.database.entity;
+
+public class Library {
+}
diff --git a/source/src/main/java/one/nem/lacerta/source/database/entity/Tag.java b/source/src/main/java/one/nem/lacerta/source/database/entity/Tag.java
new file mode 100644
index 00000000..14e293b5
--- /dev/null
+++ b/source/src/main/java/one/nem/lacerta/source/database/entity/Tag.java
@@ -0,0 +1,4 @@
+package one.nem.lacerta.source.database.entity;
+
+public class Tag {
+}