diff --git a/lib/rscons.rb b/lib/rscons.rb
index 270cde3..744a71c 100644
--- a/lib/rscons.rb
+++ b/lib/rscons.rb
@@ -17,4 +17,7 @@ module Rscons
     Object,
     Program,
   ]
+
+  class BuildError < Exception
+  end
 end
diff --git a/lib/rscons/environment.rb b/lib/rscons/environment.rb
index 7d78749..22fadaf 100644
--- a/lib/rscons/environment.rb
+++ b/lib/rscons/environment.rb
@@ -149,8 +149,7 @@ module Rscons
       @targets.each do |target, info|
         next if targets_processed.include?(target)
         unless process_target.call(target)
-          $stderr.puts "Error: failed to build #{target}"
-          break
+          raise BuildError.new("Failed to build #{target}")
         end
       end
       cache.write
diff --git a/lib/rscons/version.rb b/lib/rscons/version.rb
index 501a18c..a77bb97 100644
--- a/lib/rscons/version.rb
+++ b/lib/rscons/version.rb
@@ -1,4 +1,4 @@
 module Rscons
   # gem version
-  VERSION = "0.0.3"
+  VERSION = "0.0.4"
 end