DataMapper is an Object Relational Mapper written in Ruby. The goal is to create an ORM which is fast, thread-safe and feature rich.

To learn a little more about this project and why you should be interested,
read the Why Datamapper? page.

Recent News

DataMapper 1.2.0 released
DataMapper 1.2.0 is here!
Read more


If you're having trouble, don't forget to check the documentation, which has both references and step by step tutorials.

Read documentation


If you're still having trouble, or you think you came across something you think might be a bug, let us know.

Log a ticket


DataMapper 1.2.0 released

DataMapper 1.2.0 is here!

13 October 2011 by solnic

DataMapper 1.1.0 released

DataMapper 1.1.0 is here!

17 March 2011 by dkubb

DataMapper 1.0.2 released

DataMapper 1.0.2 is here!

07 September 2010 by dkubb

DataMapper 1.0 released

DataMapper 1.0 is here! There are changes to be aware of so please, read on.

12 June 2010 by knowtheory

DataMapper 1.0.0 rc3 released

Includes several bugs fixes for issues found in rc2, as well as a few other tickets in the queue.

27 May 2010 by dkubb

DataMapper 1.0.0 rc2 released

We are starting a public RC process now to make sure the installation process is solid and that the API is stable before 1.0 is released at RailsConf.

20 May 2010 by dkubb

DataMapper 0.10.2 is Released

New Set Operations, bug fixes and more specs round out this solid release.

11 December 2009 by dkubb

DataMapper at RubyEnRails Amsterdam 2009

Presentation on DataMapper by dbussink

07 December 2009 by myabc

DataMapper 0.10 is Released

After 11 months of work, over 1250 commits and 140 tickets fixed 0.10 is ready

15 September 2009 by dkubb

DataMapper Presented at RailsConf 2008

A warm reception for a very cool ORM

10 June 2008 by afrench

DataMapper 0.9 is Released

And you thought that The Great Refactoring was for naught

27 May 2008 by ssmoot, afrench

DataMapper Presented at MWRC 2008

Presentation on DataMapper by Wycats

10 April 2008 by afrench

Spotlight on... Laziness

The Fastest Code Is No Code

03 April 2008 by afrench

Spotlight on... Composite Keys

When a Primary Key Just Isn't Enough

29 March 2008 by afrench and ssmoot

The Great Refactoring

Change is afoot

22 March 2008 by afrench and ssmoot