1. Building by Open
Collaboration
Craig Macdonald
University of Glasgow
craigm@dcs.gla.ac.uk

2. Motivations
• Why should we have IR platforms?
– They facilitate research, by bringing researchers close
to the state‐of‐the‐art
• Why should we have !quot;#$%&!'()# IR platforms?
– They facilitate greater research potential
• Keep in contact with the commercial companies
– They provide visibility
– By contributing towards open source platforms, we
can all reap the benefits

3. History of Terrier
• 2001‐2004: Terrier started as EPSRC (British
research council) project: Iadh Ounis, Gianni
Amati, Ben He & Vassilis Plachouras form
platform. I join later.
• 2005: v1.0.0 core released by the Univ. of
Glasgow as open source under the MPL
license, followed later by v.1.0.1 and v1.0.2
• 2007: v1.1.0, v1.1.1 released
• 2008: v2.0, v2.1, v2.2 released

4. Current Terrier Core
• A framework for doing IR experimentation and
building IR apps
• Supports indexing commonly used IR research
collections (e.g. TREC). Indexing options are
direct indexing, single‐pass indexing & Map
Reduce‐based indexing
• Standard retrieval facilities, with many
weighting models, including Query Expansion
• Sample desktop search application

5. Popularity
• 5000 downloads since 2005
• Growing academic usage
– FIRE: most popular platform
– CLEF: widely used platform
– TREC: for 2008, one of most popular platforms

6. Working with users
• The discussion forum provides a place for
users to ask questions about how to use the
platform
– 650 posts from August 2005 to Feb 2009
• Allows users to help !a#$%&'$!(%

7. Working with developers
• A central benefit of open source is that others
can use and improve that software, to the
benefit of others
• We are making changes to make it easier for
patches to be accepted to Terrier
– Issue tracking [In place]
– Open source code repository [In progress]

8. Issue Tracking
Key Summary Resolution

9. Issue Tracking
• Allows people to collaborate on making
changes to Terrier
• Using the issue tracker, proposed changes can
be discussed, contributed code patches can be
attached and reviewed

10. Contributing to Terrier
1. File an issue about the proposed changes
2. Propose a patch
3. Some discussion may ensue
4. Once the patch is deemed *))#quot;+*,-#, it will
be committed by a committer
5. Next version of Terrier will include
contributed code

11. Filing an Issue
One sentence about the issue
What version of Terrier has this issue?
More details about the problem:
enough information to
reproduce the problem

12. Acceptable Patches
• Fits with Terrier’s style
– E.g. comments, javadoc, documentation
– Reuses existing code
• Can be cleanly applied (up to date with
current code)
• Does not break existing functionality
– All test cases pass
• Is agreeable to the committer

13. Open Source Code Repository
• We work on Terrier for months before releases
• However, patches need to be up‐to‐date
• In progress: open up Terrier core source
repository
• Patches can then in‐sync with current source
– Easier to commit and accept!

14. Our limitations
• Our aim is to do research
• The platform facilitates that. By having the core
platform open source we help &'$!()%do research
also
• Open source works best when &'$!()%can
contribute back as well
• We need your help to build a community – we
can’t spend all year developing code to release,
and helping users
– We can all take a share of the development and of
assisting users on the forum

15. Conclusions
• Motivations for open source IR platform
• Engaging with users
http://ir.dcs.gla.ac.uk/terrier/forum/
• Engaging with developers
http://ir.dcs.gla.ac.uk/terrier/issues/
• Filing issues and contributing patches