diff --git a/data/src/main/java/one/nem/lacerta/data/Document.java b/data/src/main/java/one/nem/lacerta/data/Document.java
new file mode 100644
index 00000000..4d966c1e
--- /dev/null
+++ b/data/src/main/java/one/nem/lacerta/data/Document.java
@@ -0,0 +1,4 @@
+package one.nem.lacerta.data;
+
+public interface Document {
+}
diff --git a/data/src/main/java/one/nem/lacerta/data/impl/DocumentImpl.java b/data/src/main/java/one/nem/lacerta/data/impl/DocumentImpl.java
new file mode 100644
index 00000000..de523b24
--- /dev/null
+++ b/data/src/main/java/one/nem/lacerta/data/impl/DocumentImpl.java
@@ -0,0 +1,4 @@
+package one.nem.lacerta.data.impl;
+
+public class DocumentImpl {
+}
diff --git a/data/src/main/java/one/nem/lacerta/data/module/DocumentModule.java b/data/src/main/java/one/nem/lacerta/data/module/DocumentModule.java
new file mode 100644
index 00000000..3ed7981b
--- /dev/null
+++ b/data/src/main/java/one/nem/lacerta/data/module/DocumentModule.java
@@ -0,0 +1,4 @@
+package one.nem.lacerta.data.module;
+
+public class DocumentModule {
+}