diff --git a/Library/Homebrew/global.rb b/Library/Homebrew/global.rb
index 6fd01d1494..e8e865976f 100644
--- a/Library/Homebrew/global.rb
+++ b/Library/Homebrew/global.rb
@@ -68,8 +68,14 @@ HOMEBREW_LOGS = Pathname.new(ENV['HOMEBREW_LOGS'] || '~/Library/Logs/Homebrew/')
 
 HOMEBREW_TEMP = Pathname.new(ENV.fetch('HOMEBREW_TEMP', '/tmp'))
 
-RUBY_BIN = Pathname.new(RbConfig::CONFIG['bindir'])
-RUBY_PATH = RUBY_BIN + RbConfig::CONFIG['ruby_install_name'] + RbConfig::CONFIG['EXEEXT']
+if RbConfig.respond_to?(:ruby)
+  RUBY_PATH = Pathname.new(RbConfig.ruby)
+else
+  RUBY_PATH = Pathname.new(RbConfig::CONFIG["bindir"]).join(
+    RbConfig::CONFIG["ruby_install_name"] + RbConfig::CONFIG["EXEEXT"]
+  )
+end
+RUBY_BIN = RUBY_PATH.dirname
 
 if RUBY_PLATFORM =~ /darwin/
   MACOS_FULL_VERSION = `/usr/bin/sw_vers -productVersion`.chomp
diff --git a/Library/Homebrew/test/testing_env.rb b/Library/Homebrew/test/testing_env.rb
index c3dcf89578..f0bd1726df 100644
--- a/Library/Homebrew/test/testing_env.rb
+++ b/Library/Homebrew/test/testing_env.rb
@@ -29,8 +29,14 @@ HOMEBREW_VERSION       = '0.9-test'
 
 require 'tap_constants'
 
-RUBY_BIN = Pathname.new(RbConfig::CONFIG['bindir'])
-RUBY_PATH = RUBY_BIN + RbConfig::CONFIG['ruby_install_name'] + RbConfig::CONFIG['EXEEXT']
+if RbConfig.respond_to?(:ruby)
+  RUBY_PATH = Pathname.new(RbConfig.ruby)
+else
+  RUBY_PATH = Pathname.new(RbConfig::CONFIG["bindir"]).join(
+    RbConfig::CONFIG["ruby_install_name"] + RbConfig::CONFIG["EXEEXT"]
+  )
+end
+RUBY_BIN = RUBY_PATH.dirname
 
 MACOS_FULL_VERSION = `/usr/bin/sw_vers -productVersion`.chomp
 MACOS_VERSION = ENV.fetch('MACOS_VERSION') { MACOS_FULL_VERSION[/10\.\d+/] }