diff --git a/Gemfile b/Gemfile
index 6bb8db6..17973b1 100644
--- a/Gemfile
+++ b/Gemfile
@@ -2,4 +2,4 @@ source 'https://rubygems.org'
 
 gem 'rake'
 gem 'jekyll'
-gem 'mini_magick'
+gem 'mini_magick', '>= 4.9.4'
diff --git a/Gemfile.lock b/Gemfile.lock
index 96080fc..c5af578 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -38,8 +38,7 @@ GEM
       rb-fsevent (>= 0.9.3)
       rb-inotify (>= 0.9)
     mercenary (0.3.3)
-    mini_magick (3.7.0)
-      subexec (~> 0.2.1)
+    mini_magick (4.9.5)
     parslet (1.5.0)
       blankslate (~> 2.0)
     posix-spawn (0.3.8)
@@ -53,7 +52,6 @@ GEM
     redcarpet (3.1.2)
     safe_yaml (1.0.3)
     sass (3.3.7)
-    subexec (0.2.3)
     timers (1.1.0)
     toml (0.1.1)
       parslet (~> 1.5.0)
@@ -64,5 +62,8 @@ PLATFORMS
 
 DEPENDENCIES
   jekyll
-  mini_magick
+  mini_magick (>= 4.9.4)
   rake
+
+BUNDLED WITH
+   1.17.3