diff --git a/.travis.yml b/.travis.yml
index 7e0080261..7f9db1f94 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -43,6 +43,10 @@ matrix:
     - rust: nightly
       script: *test_all
 
+    # Test everything on Rust 1.18.0 for backward compatibility
+    - rust: 1.18.0
+      script: *test_all
+
     # Upload docs on nightly
     - rust: nightly
       script: