diff --git a/.travis.yml b/.travis.yml
index a1a5e6f..72d9d0b 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -60,6 +60,10 @@ matrix:
       env: PKG_CONFIG_PATH="/usr/local/opt/openssl@1.1/lib/pkgconfig"
 
 
+addons:
+  apt:
+    packages:
+    - libssl-dev
 
 
 sudo: false