Agile programming methods don't have to be used in isolation.
Trans Canada Pipeline Ltd. in Calgary, Alberta, for instance, is working with two consultancies to utilize XP and Scrum for several key software development projects, according to Ken Schwaber, president of one of the consultancies, Advanced Development Methods Inc. in Lexington, Mass.
"I think a lot of the different [agile] methods tend to borrow from each other," said Martin Fowler, chief scientist at the other consultancy, Chicago-based ThoughtWorks Inc., which does application development and integration work. "If a good idea pops up in one, it often gets adopted by others as well."
Schwaber, a Scrum co-creator, said it makes sense to combine Scrum and XP because Scrum focuses on management practices and XP centers on engineering practices for building object-oriented software. "We're trying to make up for the weaknesses in both of them to have a more complete process," he said, adding that XP is geared toward small projects, while Scrum can scale to larger projects.
Agile characteristics that XP and Scrum share include heavy user input, self-organizing teams that don't rely on management to tell them what to do and incremental delivery of functional code within short time frames, with test periods at the end of each iteration, Schwaber said. Both approaches also leave room for a project to change, rather than calling for a set of fixed application requirements.
Schwaber said Trans Canada asked his company and ThoughtWorks to work together to merge Scrum and XP. Trans Canada currently has 250 to 350 people working on three development projects: one for setting up and initiating customer contracts, another for allocating and invoicing pipeline usage and a third for managing land titles, he said.
Trans Canada couldn't be reached for comment.
Schwaber's firm calls the new hybrid approach XP@Scrum. He said XP@Scrum will be discussed at several development conferences this year, starting with Software Development West next month in San Francisco.
Another firm promoting the combined use of Scrum and XP is Brighton, Mass.-based PatientKeeper Corp., whose chief technology officer is Jeff Sutherland, a co-creator of Scrum.
Mike Beedle, CEO of Chicago-based e-Architects Inc., also is documenting a Scrum/XP approach that he calls Xbreed.
Read accompanying story: