Important Dates

May 25th (new)
Papers due
May 25th
Shepherding starts
Jul 10th
Shepherding Recommendations Due
Jul 20th
Notification of Acceptance
Aug 3rd
Conference Draft Due
Aug 20th
Early Registration ends
August 27
August 24-28
Agile 2009 days
August 28
First Day of PLoP


Pattern Languages of Programs (PLoP™) conference is a premier event for pattern authors and pattern enthusiasts to gather, discuss and learn more about patterns and software development.

The conference program includes the following kinds of sessions:

PLoP will be held at the Hyatt Regency and the BootCamp at DePaul University.

Conference at a Glance

The BootCamp, a special full-day Pre-PLoP activity for newcomers, will happen on Thursday, 27th August, 8h30-17h00.

The PLoP conference starts on Friday morning, August 28th, at 7h30, with breakfast, and it will conclude on Sunday, August 30th at noon.

Invited Talks

"Making use of Context, Side-Effects and Overdose Effects in Larger Collections of Patterns"

Dr. Alistair Cockburn, Friday, 28, 09:00-10:00

As you collect more and more patterns, they should start to collide. The interesting question is What to do then? The pharmaceutical form of a pattern goes from symptoms and observations, to recommendation, and very significantly, overdose and side effects. These you might think of as "truth-in-advertising" labeling on the advice contained in the pattern; after all, too much of a good thing is no longer a good thing. In this talk, Dr. Cockburn will share what he has been doing with this pattern format in the area of project management, which matches the healthy-body (pharmaceutical) metaphor quite well. Among the dozens of patterns, several conflict. Dr. Cockburn will talk about the tagging of patterns, making use of context to combine or alternate between them.

Dr. Alistair Cockburn is an expert on patterns, use cases, project management, object-oriented design and agile methodologies. Besides helping write the Agile Manifesto and the Declaration of Interdependence, he wrote three Jolt-award books and created the Crystal family of agile methodologies. He has consulted to companies around the world from Fortune 100 companies to startups, in Scandinavia to South Africa to China. He was special advisor to the Central Bank of Norway in the late 1990s. Alistair is known for his lively presentations and original viewpoints. Many of his materials are available online at

"Transcendence and Passing Through the Gate"

Dave West, Friday, 28, 17:00-18:00

Christopher Alexander believed that Patterns and Pattern Languages were Gates, gates that practitioner had to "pass through" before they could practice "The Timeless Way." Patterns must be transcended before their true value is realized. This is not as mystical a concept as it first appears. Kent Beck, in his first exposition on eXtreme Programming (XP) also noted that the third stage of agility was transcendence of the official practices (another kind of pattern) of XP. Using agility as an exemplar, this talk will look at transcendence and offer some pointers for "passing through the Gate."

Dave West has been both a professional software developer and an academic. He has been a part of the Patterns and Agile communities since their beginning, and was a contributor to OO before that. He is the author of Object Thinking and is completing a second book on generative systems design. In addition to a consulting practice, he will be leading a unique software development degree program at New Mexico Highlands University starting this fall.

"Big Balls of Mud: Is This the Best that Agile Can Do?"

Brian Foote and Joseph Yoder, Saturday, 29, 13:30-15:00

It was back in '97 that these presenters first opined that, while much attention had been focused on high-level software architectural patterns, what is, in effect, the de-facto standard software architecture had seldom been discussed: the Big Ball of Mud. Somewhat to our astonishment, since then, no one has ever undertaken to dispute this premise. A Ball of Mud is, of course, a haphazardly structured, sprawling, sloppy, duct-tape and bailing wire, spaghetti code jungle. Is agility's utilitarian focus on process rather than design its secret weapon, or its Achilles heel?

Brian Foote is a research computer scientist with nearly thirty years of professional programming experience. He is co-author of the Big Ball of Mud Pattern, along with Joe Yoder. Brian cut his computational teeth in the realm of real-time scientific programming. The highly volatile requirements present in this domain led him to an interest in objects, reuse, software reuse, frameworks, components, and, ultimately, reflection and metalevel architectures. He has been an avid member of the object-oriented research community since 1986, and is a veteran of the early Smalltalk surge that gave birth to frameworks, GUIs, refactoring, and ultimately, agility. He has also been active in the software patterns community, and edited Pattern Languages of Program Design 4. Brian is currently a Senior Pontificator at Industrial Logic, Inc., where he has, among other things, been spreading the Gang of Four's Gospel to a new generation of developers.

Joe Yoder began working with software in the mid 1980's, and has developed robust systems for many companies and organizations with global impact. He is a founder and principle of The Refactory, Inc., a company focused on software architecture, design, implementation, consulting and mentoring of all facets of software development. Joe currently oversees a team of developers who have constructed an order fulfillment system based on enterprise architecture using the .NET environment. His other recent work includes working in both the Java and .NET environments, and deploying Domain-Specific Languages for clients. Joe thinks software is still too hard to change. He wants do something about this and believes that putting the ability to change software in the hands of the people with the knowledge to change it seems to be one promising avenue to solve this problem.

Special Workshop Session

"Social Experience Design Patterns"

Christian Crumlish and Erin Malone, Friday, 28, 10:30-11:30

The Social Design Patterns project began as an effort to document user interface and interaction patterns related to the design of digital social experiences. Many people have contributed to the current taxonomy of patterns (and related principles, anti-patterns, and emergent practices) and a version of the material is due to appear in dead-tree book form around September 28th this year from O'Reilly and Yahoo! Press. The book is called Designing Social Interfaces, and the patterns in it are available for reading (and editing!) now on a wiki at

Christian Crumlish has been participating in, analyzing, designing, and drawing social interactive spaces online since 1994. These days he is the curator of Yahoo!'s pattern library, a design evangelist with the Yahoo! Developer Network, and a member of Yahoo!'s Design Council. He is the author of the bestselling The Internet for Busy People, andThe Power of Many, and is currently working on an upcoming book, Designing Social Interfaces, with Erin Malone. He has spoken about social patterns at BarCamp Block, BayCHI, South by Southwest, the IA Summit, Ignite, and Web 2.0 Expo. Christian has a bachelor's degree in philosophy from Princeton. He lives in Oakland with his wife Briggs, his cat Fraidy, and his electric ukulele, Evangeline.

Erin Malone, Principal at Tangible ux, has over 20 years of experience leading design teams and developing web and software applications, social experiences and system-wide solutions. Prior to Tangible, she was at Yahoo! where she led the Platform User Experience Design team, founded the Yahoo! Design Pattern Library. Additionally, she led the redesign of the Yahoo! Developer Network, oversaw the redesign of Yahoo!'s Registration system, designed cross-network social solutions, developed the ux team's Intranet and worked on other cross-company initiatives. Before Yahoo!, she was a Design Director at AOL leading a range of community and personalization initiatives, Creative Director at AltaVista responsible for the AV Live portal and chief Information Architect for Zip2 which produced local city guides, entertainment guides, maps and yellow pages, including New York Today for the NYTimes. She was the founding editor-in-chief of Boxes and Arrows, a role she served for 5 years. She is the author of several articles on interaction design history and design management and a founding member of the IA Institute. Erin has a BFA in Communication Design from East Carolina University (1986), Greenville NC and an MFA in Information Design from the Rochester Institute of Technology (1994), Rochester NY. She is the author of the forthcoming book Designing Social Interfaces with Christian Crumlish for O'Reilly Media and it's related site

Interactive Pattern Story Design Workshop

James Siddle, Saturday, 29, 11:00-12:30

Interactive Pattern Stories allow readers to learn from patterns and pattern languages in a fun, engaging way. The idea is simple: combine pattern stories with interactive fiction, such as children's Choose Your Own Adventure books. The result is an interactive design narrative that readers explore to learn design alternatives and differing consequences.

However, there's a problem - complexity. Writing a compelling design story is tricky at the best of times; introducing branches for different design choices requires the writer to consider and coordinate many possible outcomes. As a result, it would seem that only simple interactive pattern stories are feasible. Further, a story with many endings may require significant amounts of overlapping narrative, which can make the stories inaccessible or boring.

This workshop introduces interactive pattern stories, provides a worked example, and poses the question: what format, structure, or devices can ease the task of writing interactive pattern stories while still allowing the reader to explore design alternatives and their consequences?

Following the presentation and worked example, which will make up the first half of the workshop, attendees will break out into groups to design an interactive pattern story with the goal of tackling the question posed above. Groups can choose to modify an existing interactive story that will be provided as a starting point, or can choose to start from scratch. So just bring yourself (and your six-sided dice) and have some fun designing an interactive design adventure.

James Siddle has been variously a software engineer, programmer, architect, and designer across several software companies during the past 11 years. In addition to writing and designing software, Jim has written and published several patterns papers, usually with a focus on practical application. He is currently in the last throes of an MSc in Software Engineering at Oxford University, and works for IBM in the UK (though is attending PLoP as an independent).

"Is that true..." Discussion

Christian Kohls and Stephanie Panke, Sunday, 30, 10:30-11:30

Whether or not patterns can be called scientific methods has filled the beer cellar of Kloster Irsee with heated discussions among “practitioners” and “researchers” during many EuroPloP conferences. The practitioners usually reject a scientific approach to patterns, arguing that good patterns contain “nothing new”, but capture existing knowledge. From their point of view, the nature of patterns is a specific and very useful genre for technical documentation. Unsurprisingly, pattern researchers beg to differ. They consider pattern mining as a scientific endeavor. Patterns reveal previously unreported regularities. In this discussion, we try to reconcile both views, by distinguishing patterns that represent scientific progress from patterns that are just another – albeit effective – genre for documentation.

Special Book Workshop

  "Social Experience Design Patterns"
      by Christian Crumlish, Erin Malone


Friday, August 28
08:00-08:30 Registration
09:00-10:00 Invited Talk I: "Making use of Context, Side-Effects and Overdose Effects in Larger Collections of Patterns"
by Dr. Alistair Cockburn
Coffee Break
10:30-11:30 Introduction to Social Patterns / Writer's Group
11:30-12:00 Pattern Workshop Demo
13:00-13:30 Games
13:30-15:00 Writer's Workshop I
15:00-15:30 Coffee Break
Writers Workshop II
Invited Talk II: "Transcendence and Passing Through the Gate"
by Dave West
Chicago Pizza
Saturday, August 29
08:30-09:00 Day Overview and Games
Writers Workshop III
Coffee Break
11:00-12:30 Interactive Pattern Stories or Writing Group
Invited Talk III: "Big Balls of Mud: Is This the Best that Agile Can Do?"
by Brian Foote and Joseph Yoder
15:00-15:30 Coffee Break
Writers' Workshop IV



Designing Social Interfaces Patterns Book Review

& Pattern Review

18:00-21:00 Chicago Dinner & BoFS
Sunday, August 30
Day Overview & Games
09:00-10:00 Writers Workshop V
Coffee Break
10:30-11:30 Book Review &
Is it True? Discussion
Closing Retrospective
12:00-13:00 Goodbye!