diff --git a/01.workspace/heave/src/str/sqlite_failed_to.rs b/01.workspace/heave/src/str/sqlite_failed_to.rs
index 3bb2847..6bdc019 100644
--- a/01.workspace/heave/src/str/sqlite_failed_to.rs
+++ b/01.workspace/heave/src/str/sqlite_failed_to.rs
@@ -19,7 +19,20 @@ pub enum FailedTo {
     PrepareStatement(rusqlite::Error),
 }
 
-impl std::error::Error for FailedTo {}
+impl std::error::Error for FailedTo {
+    fn source(&self) -> Option<&(dyn std::error::Error + 'static)> {
+        match self {
+            FailedTo::BeginTransaction(e) => Some(e),
+            FailedTo::BuildStatement => None,
+            FailedTo::CommitTransaction(e) => Some(e),
+            FailedTo::ExecuteBatch(e) => Some(e),
+            FailedTo::ExecuteQuery(e) => Some(e),
+            FailedTo::ExecuteStatement(e) => Some(e),
+            FailedTo::OpenConnection(e) => Some(e),
+            FailedTo::PrepareStatement(e) => Some(e),
+        }
+    }
+}
 
 impl std::fmt::Display for FailedTo {
     fn fmt(&self, f: &mut std::fmt::Formatter) -> std::result::Result<(), std::fmt::Error> {