diff --git a/lib/juici/callback.rb b/lib/juici/callback.rb
index <HASH>..<HASH> 100644
--- a/lib/juici/callback.rb
+++ b/lib/juici/callback.rb
@@ -10,7 +10,12 @@ module Juici
     end
 
     def process!
-      Net::HTTP.post_form(url, build.to_form_hash)
+      Net::HTTP.start(url.host, url.port) do |http|
+        request = Net::HTTP::Post.new(url.request_uri)
+        request.body = build.to_callback_json
+
+        response = http.request request # Net::HTTPResponse object
+      end
     end
 
   end
diff --git a/lib/juici/models/build.rb b/lib/juici/models/build.rb
index <HASH>..<HASH> 100644
--- a/lib/juici/models/build.rb
+++ b/lib/juici/models/build.rb
@@ -1,3 +1,4 @@
+require 'json'
 # status enum
 #   :waiting
 #   :started
@@ -114,12 +115,12 @@ module Juici
     end
 
 
-    def to_form_hash
+    def to_callback_json
       {
         "project" => self[:parent],
         "status" => self[:status],
         "url" => ""
-      }
+      }.to_json
     end
 
   end
Refactor callbacks to use raw POST body