diff --git a/.gitignore b/.gitignore
index fe3677396..1ef7e63ce 100644
--- a/.gitignore
+++ b/.gitignore
@@ -35,3 +35,4 @@ vendor/cache
 public/javascripts/wechat/node_modules/
 .ruby-version
 .access_token
+tmux*.log
diff --git a/Gemfile b/Gemfile
index afe85df1d..3bea83669 100644
--- a/Gemfile
+++ b/Gemfile
@@ -5,7 +5,7 @@ unless RUBY_PLATFORM =~ /w32/
   gem 'iconv'
   if RUBY_PLATFORM =~ /darwin/
     gem "rmagick", "= 2.15.4" ## osx must be this version
-  else
+  elsif RUBY_PLATFORM =~ /linux/
     #gem "rmagick", "= 2.13.1" ## centos yum install ImageMagick-devel
   end
   gem 'certified'