I'm trying to install therubyracer on my centos server and i'm having hella problems. $ gem install therubyracer Building native extensions. This could take a while... ERROR: Error installing therubyracer: ERROR: Failed to build gem native extension. /usr/local/rvm/rubies/ruby-1.9.3-p125/bin/ruby extconf.rb checking for main() in -lpthread... yes checking for v8.h... no *** extconf.rb failed *** C