diff --git a/.travis.yml b/.travis.yml
index 448d001..8656f16 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -79,7 +79,7 @@ matrix:
       rust: nightly
       # skip the global install step
       install:
-        - cargo install --force rustfmt-nightly
+        - cargo install --debug --force rustfmt-nightly
       script: cargo fmt -- --write-mode=diff
 
 addons: