diff --git a/README.md b/README.md
index 9e89676..19194f9 100644
--- a/README.md
+++ b/README.md
@@ -1,9 +1,23 @@
 nimforum
 ========
 
-This is Nimrod's forum. The code depends on the RST parser of
-the Nimrod compiler and on Jester.
+This is Nimrod's forum. The code depends on the RST parser of the Nimrod
+compiler and on Jester. The code generating captchas for registration uses the
+[cairo module](http://nimrod-code.org/cairo.html), which requires you to have
+the [cairo library](http://cairographics.org) installed when you run the forum,
+or you will be greeted by a cryptic error message similar to:
 
+	$ ./forum could not load: libcairo.so(1.2)
+
+If you are using macosx and have installed the ``cairo`` library through
+[MacPorts](https://www.macports.org) you still need to add the library path to
+your ``LD_LIBRARY_PATH`` environment variable. Example:
+
+	$ LD_LIBRARY_PATH=/opt/local/lib/ ./forum
+
+Replace ``/opt/local/lib`` with the correct path on your system.
+
+# Copyright
 
 Copyright (c) 2012-2013 Andreas Rumpf, Dominik Picheta.
 
diff --git a/forum.nim b/forum.nim
index 51e20fe..c95b80d 100644
--- a/forum.nim
+++ b/forum.nim
@@ -806,6 +806,11 @@ get "/newthread/?":
   resp genMain(c, genFormPost(c, "donewthread", "New thread", "", "", false),
                "Nimrod Forum - New Thread")
 
+const licenseRst = slurp("static/license.rst")
+get "/license":
+  createTFD()
+  resp genMain(c, rstToHtml(licenseRst), "Forum content license")
+
 when isMainModule:
   docConfig = rstgen.defaultConfig()
   math.randomize()
diff --git a/main.tmpl b/main.tmpl
index b0e15f5..f9bc30e 100644
--- a/main.tmpl
+++ b/main.tmpl
@@ -78,6 +78,7 @@
   <div id="footer">
   <span>Written in <a href="http://nimrod-code.org/">Nimrod</a> using <a href="https://github.com/dom96/jester">Jester</a></span>
   <span> | <a href="https://github.com/nimrod-code/nimforum">Fork on Github</a></span>
+  <span> | User contributions licensed under <a href="http://creativecommons.org/licenses/by-sa/3.0/">cc-wiki</a> with <a href="/license">attribution required</a></span>
   <span style="float:right;">Generated in ${int((epochTime()-c.startTime)*1000.0)}ms</span>
   </div>
 </body>
diff --git a/static/license.rst b/static/license.rst
new file mode 100644
index 0000000..47e5762
--- /dev/null
+++ b/static/license.rst
@@ -0,0 +1,42 @@
+Forum content license
+=====================
+
+All the content contributed to the Nimrod Forum is `cc-wiki (aka cc-by-sa)
+<http://creativecommons.org/licenses/by-sa/3.0/>`_ licensed, intended to be
+**shared and remixed**. In the future we may even provide all this data as a
+convenient data dump.
+
+But our cc-wiki licensing, while intentionally permissive, does **require
+attribution**::
+
+    **Attribution** — You must attribute the work in the manner specified by
+    the author or licensor (but not in any way that suggests that they endorse
+    you or your use of the work).
+
+Let us clarify what we mean by attribution. If you republish this content, we
+require that you:
+
+* **Visually indicate that the content is from the Nimrod Forum**. It doesn’t
+  have to be obnoxious; a discreet text blurb is fine.
+* **Hyperlink directly to the original post** (e.g.,
+  http://forum.nimrod-code.org/t/186)
+* **Show the author names** for every post.
+* **Hyperlink each author name** directly back to their user profile page
+  (e.g., http://forum.nimrod-code.org/profile/Araq)
+
+By “directly”, we mean each hyperlink must point directly to our domain in
+standard HTML visible even with JavaScript disabled, and not use a tinyurl or
+any other form of obfuscation or redirection. Furthermore, the links must not
+be `nofollowed
+<http://googleblog.blogspot.com.es/2005/01/preventing-comment-spam.html>`_.
+
+This is about the spirit of fair **attribution**. Attribution to the website,
+and more importantly, to the individuals who so generously contributed their
+time to create that content in the first place!
+
+Feel free to remix and reuse to your heart’s content, as long as a good faith
+effort is made to attribute the content!
+
+Content previous to the forum license change of
+http://forum.nimrod-code.org/t/186 remains under the original authors'
+copyright, and therefore you cannot reuse it.