File "/xxx/gratipay/gratipay.com/gratipay/main.py", line 64, in <module>
    website.db = gratipay.wireup.db(env)
  File "/xxx/gratipay/gratipay.com/gratipay/wireup.py", line 54, in db
    db = GratipayDB(dburl, maxconn=maxconn)
  File "/xxx/gratipay/gratipay.com/env/lib/python2.7/site-packages/postgres/__init__.py", line 323, in __init__
    dsn = url_to_dsn(url)
  File "/xxx/gratipay/gratipay.com/env/lib/python2.7/site-packages/postgres/__init__.py", line 217, in url_to_dsn
    dsn += " port=" + port
TypeError: coercing to Unicode: need string or buffer, int found