diff --git a/Web/Ohloh/Common.hs b/Web/Ohloh/Common.hs
new file mode 100644
--- /dev/null
+++ b/Web/Ohloh/Common.hs
@@ -0,0 +1,140 @@
+-- Copyright © 2012 Frank S. Thomas <frank@timepit.eu>
+-- All rights reserved.
+--
+-- Use of this source code is governed by a BSD-style license that
+-- can be found in the LICENSE file.
+
+-- | Common operations for "Web.Ohloh" types and convenience functions.
+module Web.Ohloh.Common where
+
+import Text.Format
+import Text.XML.HXT.Core
+
+queryPaths :: [(String, String)]
+queryPaths = [
+    ("account",             "accounts/{0}.xml"),
+    ("accounts",            "accounts.xml"),
+    ("activity_facts",      "projects/{0}/analyses/{1}/activity_facts.xml"),
+    ("analysis",            "projects/{0}/analyses/{1}.xml"),
+    ("contributor_fact",    "projects/{0}/contributors/{1}.xml"),
+    ("contributor_facts",   "projects/{0}/contributors.xml"),
+    ("enlistment",          "projects/{0}/enlistments/{1}.xml"),
+    ("enlistments",         "projects/{0}/enlistments.xml"),
+    ("factoid",             "projects/{0}/factoids/{1}.xml"),
+    ("factoids",            "projects/{0}/factoids.xml"),
+    ("kudos",               "accounts/{0}/kudos.xml"),
+    ("kudos_sent",          "accounts/{0}/kudos/sent.xml"),
+    ("language",            "languages/{0}.xml"),
+    ("languages",           "languages.xml"),
+    ("project",             "projects/{0}.xml"),
+    ("projects",            "projects.xml"),
+    ("size_facts",          "projects/{0}/analyses/{1}/size_facts.xml"),
+    ("stack",               "accounts/{0}/stacks/{1}.xml"),
+    ("stacks",              "projects/{0}/stacks.xml")
+  ]
+
+-- | Return an URL for the different items that can be queried:
+--
+-- > queryUrl "project" ["ohloh-hs"] == Just "http://www.ohloh.net/projects/ohloh-hs.xml"
+-- > queryUrl "projects" []          == Just "http://www.ohloh.net/projects.xml"
+--
+--   A list of possible items can be retrieved with @map fst 'queryPaths'@.
+queryUrl :: String -> [String] -> Maybe String
+queryUrl x args = do
+  let url = "http://www.ohloh.net/"
+  path <- lookup x queryPaths
+  return $ url ++ (format path args)
+
+-- | Append an API key to an URL, i.e.
+--
+-- > queryUrl "language" ["haskell"] `withApiKey` "YOUR_API_KEY"
+--
+--   returns @Just \"http:\/\/www.ohloh.net\/languages\/haskell.xml?api_key=YOUR_API_KEY\"@.
+withApiKey :: Maybe String -> String -> Maybe String
+withApiKey url key = fmap (++ "?api_key=" ++ key) url
+
+class ReadXmlString a where
+  readXmlString :: (XmlPickler a) => String -> Maybe a
+  readXmlString xml =
+    case runLA xread xml of
+      [] -> Nothing
+      (x:_) -> unpickleDoc xpickle x
+
+class ShowXmlString a where
+  showXmlString :: (XmlPickler a) => a -> String
+  showXmlString = showPickled []
+
+-- | Like 'uncurry' but for functions with 3 arguments.
+uncurry3 :: (t1 -> t2 -> t3 -> t) -> (t1, t2, t3) -> t
+uncurry3 f (x1, x2, x3) =
+         f  x1  x2  x3
+
+-- | Like 'uncurry' but for functions with 4 arguments.
+uncurry4 :: (t1 -> t2 -> t3 -> t4 -> t) -> (t1, t2, t3, t4) -> t
+uncurry4 f (x1, x2, x3, x4) =
+         f  x1  x2  x3  x4
+
+-- | Like 'uncurry' but for functions with 5 arguments.
+uncurry5 :: (t1 -> t2 -> t3 -> t4 -> t5 -> t) -> (t1, t2, t3, t4, t5) -> t
+uncurry5 f (x1, x2, x3, x4, x5) =
+         f  x1  x2  x3  x4  x5
+
+-- | Like 'uncurry' but for functions with 6 arguments.
+uncurry6 :: (t1 -> t2 -> t3 -> t4 -> t5 -> t6 -> t) -> (t1, t2, t3, t4, t5, t6) -> t
+uncurry6 f (x1, x2, x3, x4, x5, x6) =
+         f  x1  x2  x3  x4  x5  x6
+
+-- | Like 'uncurry' but for functions with 7 arguments.
+uncurry7 :: (t1 -> t2 -> t3 -> t4 -> t5 -> t6 -> t7 -> t) -> (t1, t2, t3, t4, t5, t6, t7) -> t
+uncurry7 f (x1, x2, x3, x4, x5, x6, x7) =
+         f  x1  x2  x3  x4  x5  x6  x7
+
+-- | Like 'uncurry' but for functions with 8 arguments.
+uncurry8 :: (t1 -> t2 -> t3 -> t4 -> t5 -> t6 -> t7 -> t8 -> t) -> (t1, t2, t3, t4, t5, t6, t7, t8) -> t
+uncurry8 f (x1, x2, x3, x4, x5, x6, x7, x8) =
+         f  x1  x2  x3  x4  x5  x6  x7  x8
+
+-- | Like 'uncurry' but for functions with 9 arguments.
+uncurry9 :: (t1 -> t2 -> t3 -> t4 -> t5 -> t6 -> t7 -> t8 -> t9 -> t) -> (t1, t2, t3, t4, t5, t6, t7, t8, t9) -> t
+uncurry9 f (x1, x2, x3, x4, x5, x6, x7, x8, x9) =
+         f  x1  x2  x3  x4  x5  x6  x7  x8  x9
+
+-- | Like 'uncurry' but for functions with 10 arguments.
+uncurry10 :: (t1 -> t2 -> t3 -> t4 -> t5 -> t6 -> t7 -> t8 -> t9 -> t10 -> t) -> (t1, t2, t3, t4, t5, t6, t7, t8, t9, t10) -> t
+uncurry10 f (x1, x2, x3, x4, x5, x6, x7, x8, x9, x10) =
+          f  x1  x2  x3  x4  x5  x6  x7  x8  x9  x10
+
+-- | Like 'uncurry' but for functions with 11 arguments.
+uncurry11 :: (t1 -> t2 -> t3 -> t4 -> t5 -> t6 -> t7 -> t8 -> t9 -> t10 -> t11 -> t) -> (t1, t2, t3, t4, t5, t6, t7, t8, t9, t10, t11) -> t
+uncurry11 f (x1, x2, x3, x4, x5, x6, x7, x8, x9, x10, x11) =
+          f  x1  x2  x3  x4  x5  x6  x7  x8  x9  x10  x11
+
+-- | Like 'uncurry' but for functions with 13 arguments.
+uncurry13 :: (t1 -> t2 -> t3 -> t4 -> t5 -> t6 -> t7 -> t8 -> t9 -> t10 -> t11 -> t12 -> t13 -> t) -> (t1, t2, t3, t4, t5, t6, t7, t8, t9, t10, t11, t12, t13) -> t
+uncurry13 f (x1, x2, x3, x4, x5, x6, x7, x8, x9, x10, x11, x12, x13) =
+          f  x1  x2  x3  x4  x5  x6  x7  x8  x9  x10  x11  x12  x13
+
+-- | Like 'uncurry' but for functions with 14 arguments.
+uncurry14 :: (t1 -> t2 -> t3 -> t4 -> t5 -> t6 -> t7 -> t8 -> t9 -> t10 -> t11 -> t12 -> t13 -> t14 -> t) -> (t1, t2, t3, t4, t5, t6, t7, t8, t9, t10, t11, t12, t13, t14) -> t
+uncurry14 f (x1, x2, x3, x4, x5, x6, x7, x8, x9, x10, x11, x12, x13, x14) =
+          f  x1  x2  x3  x4  x5  x6  x7  x8  x9  x10  x11  x12  x13  x14
+
+-- | Like 'uncurry' but for functions with 15 arguments.
+uncurry15 :: (t1 -> t2 -> t3 -> t4 -> t5 -> t6 -> t7 -> t8 -> t9 -> t10 -> t11 -> t12 -> t13 -> t14 -> t15 -> t) -> (t1, t2, t3, t4, t5, t6, t7, t8, t9, t10, t11, t12, t13, t14, t15) -> t
+uncurry15 f (x1, x2, x3, x4, x5, x6, x7, x8, x9, x10, x11, x12, x13, x14, x15) =
+          f  x1  x2  x3  x4  x5  x6  x7  x8  x9  x10  x11  x12  x13  x14  x15
+
+-- | Like 'uncurry' but for functions with 16 arguments.
+uncurry16 :: (t1 -> t2 -> t3 -> t4 -> t5 -> t6 -> t7 -> t8 -> t9 -> t10 -> t11 -> t12 -> t13 -> t14 -> t15 -> t16 -> t) -> (t1, t2, t3, t4, t5, t6, t7, t8, t9, t10, t11, t12, t13, t14, t15, t16) -> t
+uncurry16 f (x1, x2, x3, x4, x5, x6, x7, x8, x9, x10, x11, x12, x13, x14, x15, x16) =
+          f  x1  x2  x3  x4  x5  x6  x7  x8  x9  x10  x11  x12  x13  x14  x15  x16
+
+-- | Like 'uncurry' but for functions with 17 arguments.
+uncurry17 :: (t1 -> t2 -> t3 -> t4 -> t5 -> t6 -> t7 -> t8 -> t9 -> t10 -> t11 -> t12 -> t13 -> t14 -> t15 -> t16 -> t17 -> t) -> (t1, t2, t3, t4, t5, t6, t7, t8, t9, t10, t11, t12, t13, t14, t15, t16, t17) -> t
+uncurry17 f (x1, x2, x3, x4, x5, x6, x7, x8, x9, x10, x11, x12, x13, x14, x15, x16, x17) =
+          f  x1  x2  x3  x4  x5  x6  x7  x8  x9  x10  x11  x12  x13  x14  x15  x16  x17
+
+-- | Like 'uncurry' but for functions with 18 arguments.
+uncurry18 :: (t1 -> t2 -> t3 -> t4 -> t5 -> t6 -> t7 -> t8 -> t9 -> t10 -> t11 -> t12 -> t13 -> t14 -> t15 -> t16 -> t17 -> t18 -> t) -> (t1, t2, t3, t4, t5, t6, t7, t8, t9, t10, t11, t12, t13, t14, t15, t16, t17, t18) -> t
+uncurry18 f (x1, x2, x3, x4, x5, x6, x7, x8, x9, x10, x11, x12, x13, x14, x15, x16, x17, x18) =
+          f  x1  x2  x3  x4  x5  x6  x7  x8  x9  x10  x11  x12  x13  x14  x15  x16  x17  x18
diff --git a/ohloh-hs.cabal b/ohloh-hs.cabal
--- a/ohloh-hs.cabal
+++ b/ohloh-hs.cabal
@@ -1,5 +1,5 @@
 name:               ohloh-hs
-version:            0.0.1
+version:            0.0.2
 synopsis:           Interface to the Ohloh API
 description:
   ohloh-hs is an interface to the Ohloh API (<http://www.ohloh.net>), which
@@ -29,6 +29,7 @@
                     Web.Ohloh.Account
                     Web.Ohloh.ActivityFact
                     Web.Ohloh.Analysis
+                    Web.Ohloh.Common
                     Web.Ohloh.ContributorFact
                     Web.Ohloh.ContributorLanguageFact
                     Web.Ohloh.Enlistment
