diff --git a/.travis.yml b/.travis.yml
index 2c23c971..3a2316ea 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,4 +1,5 @@
 matrix:
+  fast_finish: true
   include:
     - os: linux
       env: GITSECRET_DIST="deb"; DOCKER_DIST="debian";
@@ -19,10 +20,22 @@ matrix:
       env: GITSECRET_DIST="none"; GITSECRET_GPG_DEP="gnupg"; SECRETS_GPG_COMMAND="gpg"
       sudo: required
       language: ruby
+      addons:
+        apt:
+          sources:
+          - debian-sid
+          packages:
+          - shellcheck
     - os: linux
       env: GITSECRET_DIST="none"; GITSECRET_GPG_DEP="gnupg2"; SECRETS_GPG_COMMAND="gpg2"
       sudo: required
       language: ruby
+      addons:
+        apt:
+          sources:
+          - debian-sid
+          packages:
+          - shellcheck
     - os: osx
       env: GITSECRET_DIST="brew"; GITSECRET_GPG_DEP="gnupg"; SECRETS_GPG_COMMAND="gpg"
       sudo: false