diff --git a/src/proxy_datastore.cpp b/src/proxy_datastore.cpp
index 67a3cb3..32b148a 100644
--- a/src/proxy_datastore.cpp
+++ b/src/proxy_datastore.cpp
@@ -94,7 +94,7 @@
     return m_datastore->schema();
 }
 
-std::optional<std::string> ProxyDatastore::inputDatastorePath()
+std::optional<std::string> ProxyDatastore::inputDatastorePath() const
 {
     return m_inputPath;
 }