new_contents: """ Formula for building zeromq """
  from pakit import Archive, Recipe
  
  
  class Zeromq(Recipe):
      """
      Library for standard inter language connections.
      """
      def __init__(self):
          super(Zeromq, self).__init__()
          self.src = 'https://github.com/zeromq/libzmq'
          self.homepage = 'http://zeromq.org'
          archive = Archive('https://github.com/zeromq/libzmq/releases/download/v4.2.1/zeromq-4.2.1.tar.gz',
                            hash='27d1e82a099228ee85a7ddb2260f40830212402c605a4a10b5e5498a7e0e9d03')
          self.repos = {
              'stable': archive,
              'unstable': archive,
          }
  
      def build(self):
          self.cmd('./autogen.sh')
          self.cmd('./configure --prefix={prefix}')
          self.cmd('make -j 4 all')
          self.cmd('make install')
  
      def verify(self):
          lines = self.cmd('curve_keygen').output()
          assert lines[0].find('CurveZMQ keypair') != -1
  
subject: Add zeromq.