--- a/MANIFEST.txt
+++ b/MANIFEST.txt
@@ -1,9 +1,6 @@
 README.md
 CHANGELOG.md
-ext/duktape/duktape.c
-ext/duktape/duktape.h
 ext/duktape/duktape_ext.c
-ext/duktape/duk_config.h
 ext/duktape/extconf.rb
 lib/duktape/version.rb
 lib/duktape.rb
--- a/ext/duktape/extconf.rb
+++ b/ext/duktape/extconf.rb
@@ -1,6 +1,64 @@
 require 'mkmf'
 require 'zlib'
 
+#
+# functions
+#
+
+def package_config pkg, options={}
+  package = pkg_config(pkg)
+  return package if package
+
+  begin
+    require 'rubygems'
+    gem 'pkg-config', (gem_ver='~> 1.1')
+    require 'pkg-config' and message("Using pkg-config gem version #{PKGConfig::VERSION}\n")
+  rescue LoadError
+    message "pkg-config could not be used to find #{pkg}\nPlease install either `pkg-config` or the pkg-config gem per\n\n    gem install pkg-config -v #{gem_ver.inspect}\n\n"
+  else
+    return nil unless PKGConfig.have_package(pkg)
+
+    cflags  = PKGConfig.cflags(pkg)
+    ldflags = PKGConfig.libs_only_L(pkg)
+    libs    = PKGConfig.libs_only_l(pkg)
+
+    Logging::message "PKGConfig package configuration for %s\n", pkg
+    Logging::message "cflags: %s\nldflags: %s\nlibs: %s\n\n", cflags, ldflags, libs
+
+    [cflags, ldflags, libs]
+  end
+end
+
+def duktape_try_compile
+  try_compile "int main() {return 0;}", "", {werror: true}
+end
+
+def add_cflags(flags)
+  print "checking if the C compiler accepts #{flags}... "
+  with_cflags("#{$CFLAGS} #{flags}") do
+    if duktape_try_compile
+      puts 'yes'
+      true
+    else
+      puts 'no'
+      false
+    end
+  end
+end
+
+#
+# main
+#
+
+if ENV['CC']
+  RbConfig::CONFIG['CC'] = RbConfig::MAKEFILE_CONFIG['CC'] = ENV['CC']
+end
+$LIBS << " #{ENV["LIBS"]}"
+$LDFLAGS << " #{ENV["LDFLAGS"]}"
+add_cflags(ENV["CFLAGS"])
+
+package_config('duktape')
+
 $CFLAGS += ' -std=c99'
 have_func 'rb_sym2str'
 create_makefile 'duktape_ext'