Hi Martin, On May 10, 2012, at 7:27 PM, Martin Schönberger wrote:
> Hello again! > > First of all, let me express my thanks to all of you who joined in on > this thread (started at > http://lists.xwiki.org/pipermail/devs/2012-April/050416.html) to > support me in my quest to better understand the way open source > development works in XWiki. :) > > As I've mentioned in my last email, I have some more questions I would > like to ask. Last time I focused on general aspects of the process, > today's topics revolve around the project's architecture, roles and > governance, and knowledge management. > > So my first question this time concerns the architectural design, and > how it has evolved over time. Did the basic structure change / grow > significantly since the early days of XWiki? Vincent mentioned the > change from a monolithic code to small modules. Were these and other > changes made in some major refactorings, or rather through steady > refinement? To what degree is it an issue to keep backwards > compatibility between releases? We've decided a long time ago (we = the committers at that time) that we preferred evolution rather than revolution. The main reason is that XWiki already had an important user base when the development team was started (before that it was just Ludovic working on it). It takes more time but it allows us to keep existing users happy. In addition we've been able to still move forward. There's a Joel Spolsky blog about this topic: http://www.joelonsoftware.com/articles/fog0000000069.html I don't have any figure I can prove but I'd say we've modified a bit more than half of the code in a 5 years time span (maybe up to 75%). I can cite 2 examples of relatively large refactorings we've done without breaking backward compatibility: * The Rendering module. XWiki had a wiki syntax initially and we wanted to fully rewrite the code that takes an input in that syntax and generate HTML out of it. So we created a new Rendering engine that can take any input in any syntax and generate an output in any other syntax (see http://rendering.xwiki.org). And we added polyglot support in XWiki (ie the ability to support several wiki syntaxes), and introduced XWiki Syntax 2.0. * The WYSIWYG editor. We were using TinyMCE and switched to our own editor that we wrote from scratch. If you're interested we can explain the reason… Then we have a lot of smaller refactorings. We can go into more details if you're interested. The only big part that hasn't been refactored yet is the core Model. I'd really like to tackle this and we've started designing the new model a bit but it's complex and requires a long period of focused time which I personally haven't been able to get so far. We're very serious on backward compatibility and most wiki pages back from 5 years ago still work on the latest version. We've defined a precise strategy to ensure we don't break backward compatibility: http://dev.xwiki.org/xwiki/bin/view/Community/DevelopmentPractices#HBackwardCompatibility If you're interested in how we came up with this, it should be easy to find the mailing list threads about it on xwiki.markmail.com > Also I am interested more closely how the functions and > responsibilities are divided in the team. Caty wrote about 'very clear > departments' in her last answer, and the teampage on XWiki.com lists a > multitude of different and specific roles. Both of your descriptions > of the testing process, however, suggests a less strict separation of > tasks. So what role do the roles play? How specialized or > cross-functional are the teams and people working therein? Is there a > difference between XWiki.org and XWiki SAS? At the open source project level we have only 2 roles: * contributors: anyone contributing as defined here: http://dev.xwiki.org/xwiki/bin/view/Community/Contributing * committers: people who have right access to the SCM and who can vote, see http://dev.xwiki.org/xwiki/bin/view/Community/Committership Committers decide what they want to work on. Some can be more design-oriented, others more test-oriented, etc. At XWiki SAS we have more roles and a more traditional structure. Tech roles: * CTO (me ;)) * Tech Lead or Senior Dev * Web Developers * Back end Developer * Tester * QA engineer * Designer > In a related matter, many of the role descriptions of the core > developers contain manager and leadership titles. Hmm. Do you have a link? AFAIK we just have committers. > What, in practice, > are the main tasks of the people managing the development? There's nobody managing the development ;) We're auto-managed. Committers make proposals or start votes and others discuss and vote. We do stuff by collegial agreements. > Many > meritocracies have safety nets, some rules to follow or people to go > to when no consensus can be reached on important topics. Did this ever > occur in XWiki? What would be done in such a situation? It happens rarely. We do frequently don't agree on some details. The proposals or vote is then discussed and amended with a new proposal/vote. Example: * First vote: http://markmail.org/thread/56v5thsj6wv7tpno * Second vote: http://markmail.org/thread/tino4ngttflc5i3s Sometimes it takes longer to reach a consensus but it's always a better result IMO. Nobody in this community votes -1 without a good reason just to bother people ;) > Have either > the formal roles or the informal merit people earned in a special > field some kind of influence on the weight of their voice in a > dispute? Everyone has the same vote power but then people have more influence than others through their past actions. > And last but not least some questions about the access and > distribution of knowledge: XWiki features an extensive written > documentation of itself and the process used in its development. What > is the role then of additional, personal communication, of the > proverbial informal talk at the water cooler? Is the necessary time > and ceremony of written documentation always justified by making the > knowledge permanently available to everyone, or can you think of > exceptions? We try to make it as easy as possible for someone external to follow the development or join the team. We also try to have a common style for writing code. This is needed before there's no ownership of the code and everyone can modify any part of the code. Also homogenous code also makes it easier to join the dev team. Of course we have lots of informal discussion on the mailing list and on IRC (and people speak with other privately too but all proposals/decisions are always made publicly). Hope it helps, -Vincent > Again, every answer or comment is greatly appreciated, > > Martin _______________________________________________ devs mailing list [email protected] http://lists.xwiki.org/mailman/listinfo/devs
