diff --git a/.github/workflows/main-ci.yml b/.github/workflows/main-ci.yml
index d4088c06..d1ea0b71 100644
--- a/.github/workflows/main-ci.yml
+++ b/.github/workflows/main-ci.yml
@@ -14,7 +14,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        php_version: ["7.0", "7.1", "7.2", "7.3", "7.4", "8.0"]
+        php_version: ["5.6", "7.0", "7.1", "7.2", "7.3", "7.4", "8.0"]
         service: [php-fpm, php-worker, workspace, laravel-horizon]
     steps:
     - uses: actions/checkout@v2
diff --git a/env-example b/env-example
index d024d11d..2600dc9c 100644
--- a/env-example
+++ b/env-example
@@ -321,7 +321,7 @@ LARAVEL_HORIZON_IMAGEMAGICK_VERSION=latest
 LARAVEL_HORIZON_INSTALL_SOCKETS=false
 LARAVEL_HORIZON_INSTALL_YAML=false
 LARAVEL_HORIZON_INSTALL_ZIP_ARCHIVE=false
-LARAVEL_HORIZON_INSTALL_PHPREDIS=true
+LARAVEL_HORIZON_INSTALL_PHPREDIS=false
 LARAVEL_HORIZON_INSTALL_MONGO=false
 LARAVEL_HORIZON_INSTALL_CASSANDRA=false
 LARAVEL_HORIZON_INSTALL_FFMPEG=false
diff --git a/laravel-horizon/Dockerfile b/laravel-horizon/Dockerfile
index 194f615b..10cf90eb 100644
--- a/laravel-horizon/Dockerfile
+++ b/laravel-horizon/Dockerfile
@@ -35,7 +35,11 @@ RUN apk --update add wget \
   procps
 
 RUN docker-php-ext-install mysqli mbstring pdo pdo_mysql tokenizer xml pcntl
-RUN pecl channel-update pecl.php.net && pecl install memcached mcrypt-1.0.1 && docker-php-ext-enable memcached
+RUN if [ $(php -r "echo PHP_MAJOR_VERSION;") = "5" ]; then \
+  pecl channel-update pecl.php.net && pecl install memcached-2.2.0 mcrypt-1.0.1 && docker-php-ext-enable memcached \
+;else \
+  pecl channel-update pecl.php.net && pecl install memcached mcrypt-1.0.1 && docker-php-ext-enable memcached \
+;fi
 
 # Add a non-root user to help install ffmpeg:
 ARG PUID=1000