diff --git a/src/docId/index.ts b/src/docId/index.ts
index 1378ad8a..173cdadf 100644
--- a/src/docId/index.ts
+++ b/src/docId/index.ts
@@ -1,4 +1,7 @@
-class DocId {}
+class DocId {
+  /** Just to not let the class empty, which was causing a TS bug - #103 */
+  _metaDocId = 0
+}
 
 /**
  * A special sentinel to refer to the ID of a document.