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+# MapIt
+
+A web service to map postcodes to administrative boundaries and more.
+
+MapIt was created and is maintained by [mySociety](https://github.com/mysociety/mapit) version, it's recommended you read their [README](https://github.com/mysociety/mapit/blob/master/README.rst) as well.
+
+## Development
+
+This fork of MapIt should avoid adding features, changing behaviours, or touching the code of MapIt itself. The only [differences against the original repo](https://github.com/mysociety/mapit/compare/master...alphagov:master) should only be to help integrate it into the GOV.UK stack. This allows our fork to be kept up to date with the mySociety version.
+
+So far this includes;
+
+ - [Pinning to specific versions of Python dependencies](https://github.com/alphagov/mapit/pull/1), for reliability
+ - [Adding a Procfile](https://github.com/alphagov/mapit/pull/2), to standardise deployment with other apps
+ - [A GOV.UK specific README](https://github.com/alphagov/mapit/pull/3), to provide context for GOV.UK developers
+
+## Technical documentation
+
+MapIt is a Python/Django application (backed by PostgreSQL), that provides
+RESTful API for looking up postcodes, council boundaries, etc.
+
+### Dependencies
+
+MapIt has no dependencies on the rest of the GOV.UK stack, but does use PostgreSQL
+with some geo-spatial extensions. For the GOV.UK VM these are documented in [puppet](https://github.gds/gds/puppet/blob/master/modules/govuk/manifests/apps/mapit.pp), or you can follow the [standalone install guide](http://mapit.poplus.org/docs/self-hosted/install/).
+
+### Running the application
+
+You'll need to be in a [virtualenv](http://docs.python-guide.org/en/latest/dev/virtualenvs/), and install dependencies with:
+
+```pip install -r requirements.txt```
+
+You can then run an instance of mapit with:
+
+```manage.py runserver 127.0.0.1:3108```
+
+## Licence
+
+[GNU Affero GPL](LICENCE.txt)
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-MapIt
-=====
-
-MapIt is an open source project to help people run a web service that maps
-geographical points to administrative areas. It is useful for anyone who has
-the co-ordinates of a point on Earth, and who needs to find out what country,
-region, city, constituency, or state it lies within. It’s also great for
-looking up the shapes of all those boundaries.
-
-It was created in 2003 by `mySociety <http://www.mysociety.org/>`__, a UK
-charity, for use by their various tools needing admin area lookup.
-
-Installation
-------------
-
-MapIt can be installed as a Django app, or as a standalone server. For full
-details, please see our site at http://code.mapit.mysociety.org/ for help
-and documentation.
-
-Examples
---------
-
-`mySociety <http://www.mysociety.org>`__ runs public installations of MapIt that
-you might be able to use:
-
-    * `MapIt Global <http://global.mapit.mysociety.org/>`_ - global boundaries
-      from the `OpenStreetMap <http://www.openstreetmap.org/>`_ project.
-    * `MapIt UK <http://mapit.mysociety.org/>`_ - UK boundaries from various
-      sources.
-
-The above are free for non-commercial, low-volume use. For details of
-what constitutes "low-volume", and for commercial licensing arrangements,
-please consult `MapIt Usage and Licensing
-<http://mapit.mysociety.org/licensing>`_ .
-
-
-Rate limiting
--------------
-
-Usage is rate limited by default; clients may be rate limited by IP address
-or by a User Token passed in the User-Agent: header. Clients may be excluded
-from the effects of rate limiting via the RATE_LIMIT option in the
-configuration file.