diff --git a/.travis.yml b/.travis.yml
index 79f775399..e6943fadd 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,8 +1,13 @@
 language: bash
-install:
-  - ./ci/install.sh
+sudo: false
+
+addons:
+  apt:
+    sources:
+      - debian-sid
+    packages:
+      - shellcheck
 script:
   - ./ci/build.sh
 notifications:
   email: false
-sudo: required
diff --git a/ci/build.sh b/ci/build.sh
index 798bd39ee..ea84f72f4 100755
--- a/ci/build.sh
+++ b/ci/build.sh
@@ -1,46 +1,52 @@
 #!/usr/bin/env bash
-set -eo pipefail
+set -o pipefail
 [[ "${DEBUG:-}" ]] && set -x
 
 declare -i failed
 failed=0
 
 success() {
   printf "\r\033[2K  [ \033[00;32mOK\033[0m ] Checking %s...\n" "$1"
 }
 
 fail() {
 	printf "\r\033[2K  [\033[0;31mFAIL\033[0m] Checking %s...\n" "$1"
 	failed=1
 }
 
 check() {
   local script="$1"
-  shellcheck "$script" || fail "$script"
-  success "$script"
+  if shellcheck "$script"; then
+	success "$script"
+  else
+	fail "$script"
+  fi
 }
 
 find_prunes() {
   local prunes="! -path './.git/*'"
   if [ -f .gitmodules ]; then
-    while read module; do
+    while read -r module; do
       prunes="$prunes ! -path './$module/*'"
     done < <(grep path .gitmodules | awk '{print $3}')
   fi
   echo "$prunes"
 }
 
 find_cmd() {
-  echo "find . -type f -and \( -perm +111 -or -name '*.sh' \) $(find_prunes)"
+  echo "find . -type f -and \( -perm /111 -or -name '*.sh' \) $(find_prunes)"
 }
 
 check_all_executables() {
   echo "Checking executables and .sh files..."
-  eval "$(find_cmd)" | while read script; do
+  while read -r script; do
     head=$(head -n1 "$script")
+    [[ "$head" =~ .*ruby.* ]] && continue
+    [[ "$head" =~ .*zsh.* ]] && continue
+    [[ "$head" =~ ^#compdef.* ]] && continue
     check "$script"
-  done
+  done < <(eval "$(find_cmd)")
   exit $failed
 }
 
 check_all_executables
diff --git a/ci/install.sh b/ci/install.sh
deleted file mode 100755
index c66b56c59..000000000
--- a/ci/install.sh
+++ /dev/null
@@ -1,10 +0,0 @@
-#!/bin/bash
-set -eo pipefail
-
-main() {
-  local filename="shellcheck_0.3.7-1_amd64.deb"
-  wget "http://ftp.debian.org/debian/pool/main/s/shellcheck/$filename"
-  sudo dpkg -i "$filename"
-}
-
-main