diff --git a/.travis.yml b/.travis.yml
index 5b02332..c3b53bb 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,4 +1,4 @@
 language: bash
 script: make test
 before_install:
-    - sudo apt-get install bc
\ No newline at end of file
+    - sudo apt-get install bc tmux
\ No newline at end of file