Announcing the Arch Decisions plugin for Redmine

February 23, 2010

I’ve been silent for a long time on this blog for two important reasons:

  1. I’ve decided not to post anything unless I really have some value to add
  2. I’ve been spending my spare time working on an open source plugin for the Redmine platform

So, without further ado, I’d like to announce the release (of version 0.0.8!) of the Redmine Arch Decisions plugin! At Sakonnet, my previous gig, they were using Quickbase to track tasks, specs, and just about everything. It was a snap to add in a new feature to track “architecture” (or technical) decisions, configure notifications for collaboration, and hook them up to our issues trackers for reference and follow-up. ¬†I wrote about this tool in a previous blog post, and I have been known to make the comment before that I couldn’t imagine working on software again without it. Well, when the time came to move on, guess what? No tool for tracking my “arch decisions”.

Fortunately, my current employers at Integritas are open to trying out new ideas, and are using the Rails-based Redmine for their issue tracking. Redmine, as with Rails in general, has a fairly usable plugin framework, and it was a great opportunity for me to get my hands dirty with RoR, so I jumped to it. Now, on the date of the release of the 8th version of my plugin (which we have been using for our projects), I feel I’m ready enough to announce it to anyone who’s looking for a way to record their technical decisions (and discuss them before they get made) without the overhead of stiff formal documents.

The following is a very brief overview of what you get in Redmine Arch Decisions 0.0.8:

Arch Decisions

Listing of Arch Decisions

The plugin includes a listing of the Arch Decisions themselves, which are currently limited to the scope of a single project. The ADs have an ID, a status, a summary, and a “Problem Description” field for more detailed information on the context of the decision. ADs currently follow a very simple workflow that isn’t being enforced, but is still useful:

  1. Not Started
  2. Under Discussion
  3. Decision Made
  4. Work Scheduled (implies that issues and/or tasks have been registered to track the implementation)
  5. Implemented (implies that all said issues and/or tasks have been completed, or at least to the satisfaction of the scope of the decision)
  6. Canceled
  7. Deprecated (implies that there’s another AD out there somewhere to replace it)

Arch Decisions also have a text field called “Resolution” that should be filled out when the status is changed to “Decision Made”. The resolution should explain what the final decision was, summarize why that decision was made, and provide any additional guidance to any developers who will be making sure the AD gets implemented.

Basic information for an Arch Decision

In addition to those basic text fields, there are also important supplemental elements embedded within the decisions that play an important role in the documentation and decision-making process (note that these are a new feature that I didn’t have in the old Quickbase version):

Factors

Factors associated with an AD

One of the most important benefits of tracking technical decisions in this way is the possibility of making all decision points and trade offs explicit. There are so many reasons why this is important :

  • You can see on one place all the reasons for which a decision was made
  • You can weigh them against one another so that no one gets fixated on a single reason
  • You can truly validate your assumptions by making them visible and discussing them individually
  • If any of these reasons change in the future, you can go back and check to see if your decision is still valid

Taking a cue from Craig Larman and others, I call these reasons “Factors”. A factor can be just about anything – a requirement, a hunch, a feature, a factoid – that can be used as a justification for a particular decision. In my personal experience, I have seen these factors tossed about with reckless and wanton abandon, littering the sacred grounds of a design discussion. The RAD plugin attempts to put a little order to this chaos by giving you one place to record this information. In general, it can be detrimental to the flow of a discussion to continuously stop to record these factors, but it can be extremely productive to let the fur fly in the heat of the moment, and then carefully pick out the key factors afterwards when you’re ready to clean house.

Factors have a status, which is important in showing which ones have been “challenged” (by marking them as “Validated” once the discussion has completed), including ones that were later shown to be incorrect assumptions (“Refuted”). There is even a text field called “Evidence” wherein the user can record exactly how they came to the conclusion regarding the validity (via external URLs, quotes from a discussion, or even a lame but honest “because Tim said so”).

Also importantly, factors can be reordered on the AD view page by simply dragging a row and placing it in the order desired. This allows you to explicitly declare which factors have a greater weight or priority, which comes in useful when a trade off must be made.

One interesting thing to note about factors is that they may have varying scopes. Some may be very specific to the Arch Decision at hand (e.g. “We will get a big bonus if we pick Strategy A!” or “The coin said ‘heads'”). Some may related to more than one AD (e.g. “The company has mandated that we use open source tools for this project”). Still others may be “global truths” that can even be applied across multiple projects (e.g. “Amazon EC2 does not support multicast between instances” (can this one be refuted yet?)). Factors can be created on their own (via the separate Factors tab), or right in the AD itself. In the latter case, they are automatically given a scope of “Arch Decision”. But this can be changed to something a little more broad. When this happens, the Factor can then be added to multiple ADs as appropriate.

Strategies

Strategies for an AD

What’s a decision without options to choose from? As with factors, my experience has been that people are good at tossing out ideas, but less good at remembering what they were later on. Or understanding anyone’s ideas but their own. So the RAD plugin also separates out a section just to track what those alternatives were that everyone proposed. Each one has a “short name”, which can be useful as reference (a little better than “wait, are you talking about the one where command comes in as a message which is then republished, or the one where you stick the command in the database and then you have a periodic task to look them up?”), plus a sightly longer summary. Then there is a detailed description for what that stratesugy would really entail.

Importantly, strategies can then be officially “rejected”, with an explanation as to why (in the future, it might be interesting to point to the key Factors). When this happens, they show up at the bottom of the list, with a big red “X” so that no one is confused as to whether or not that possibility is still being discussed (nor why it was rejected).

In some cases, you have a “there can only be one” situation, where a decision could only be considered to have been made when all the other competing strategies have been rejected. In this case, the Resolution will really just be a rewrite of the surviving strategy and its implications. In other cases, you might have multiple winners, each of which composes a part of the final resolution. I find this is especially the case when you are making decisions regarding standards – some will be rejected, while others will be accepted and adopted.

Tracking

An Issue with two related ADs

With this release, ADs can finally be associated with Redmine Issues. This is very important for tracking and governance (making sure the decision gets carried out, and that it is still followed in later implementations. It’s also true that during the course of making a decision, work has to be done on the side. Thus, the association between ADs and issues includes the “type” of relationship that an Issue bears to the AD:

  • Task – the work is a task related to making the decision (e.g. for research)
  • Proof of Concept – partial implementation projects that are required to prove whether or not a particular strategy is viable
  • Implementation – software development work intended to implement a decision (e.g. the creation of a framework according to the design specifications stipulated by the resolution)
  • Governed – implementation of the issue is expected to follow the guidelines laid out by a (possibly previously-existing) decision

Since I often work with issue trackers other than Redmine (and have been too lazy to implement a real integration), it’s also possible to define an Issue by an external URL rather than via a Redmine ID. Although the external tracker won’t have a back reference to the AD, and the AD won’t be able to report on the status of the issue, it’s certainly better than having no link at all.

Collaboration

The heart of the original idea for Arch Decisions was the ability to provide a voice to everyone involved in a decision. Ivory tower type architects would do well to take heed and use this tool. Developers don’t always like to have their instructions handed to them on a silver platter (especially when they think a bowl would be better for the soup they’re expected to eat). The RAD plugin gives developers the chance to speak up by posting comments in the Discussion sections (in fact, there’s one for each Factor and Strategy as well as the main AD itself, for those times when you need to focus on a specific subject). It also gives other project members a chance to respond, since there is a “watch” feature, and change notifications can go out via email.

In the previous incarnation of Arch Decisions, there was also a button on each issue so that a developer could raise a red flag whenever there was an implementation detail that needed to be discussed. Thus, the discussion could go both ways, so that architects are not always kept in the blue about what the developers are doing, and what they need to know. This worked very well at my last place of work. Unfortunately, I haven’t implemented this feature yet, but I’m sure it won’t be long before I do.

Final Details

Installing the plugin is very straightforward: just download Redmine and follow its basic instructions, then download the plugin, stick it in the /vendors/plugins folder, and run “rake db:migrate_plugins” to set up the database. I’ll provide a more extensive guide in another post, but hopefully that’s enough to get you started.¬†Unfortunately, the plugin only works with version 0.8.4 of Redmine. I’d like to get it working for 0.9.x soon, so if that’s important to you, give me a holler to get off my butt.

I’ve got more tips and details to discuss about the plugin, so I’ll try to get around to that as soon as possible. Until then, let me know if you have any feedback, and I really wish you the best in your future decisions!


Do we need Yet Another Method to communicate?

March 10, 2009

Lately I’ve been looking into Web 2.0-type tools to improve our commumication and workflow at work. There’s been some Enterprise 2.0 buzz about Twitter as a possible tool for communication on projects, and I’ve been scratching my head trying to figure out exactly how. One problem with Twitter is that it is wide out in the open, for anyone to read. If loose lips sink ships, Twitter is the Bermuda Triangle of company secrets. It hardly seems wise to be encouraging your employees to discuss the intacies of internal projects in such an open forum.

I recently came across Yammer, which is an enterprise-friendly version of Twitter. Basically, it’s the same thing, but your comments are only visible to members of your “company” (currently defined by the domain name of your email address). There are other features like private groups, but you get the idea.

Now, there’s been a lot of talk recently about the importance of quiet time for productivity (c.f. The Productive Programmer). To many “yammers” (or “yams”…?) might appear to be nothing more than an acronym for “Yet Another Method to Molest Everyone Relentlessly”. If there’s nothing more to this Yammer thing than posting your whims to the world, I wholeheartedly agree. We already use email for correspondence, IM for more immediate communication, Skype for voice and text conferences, web forums for context-related discussions, wikis, and on and on. So who needs yet another open window on our desktop, yet another way to have your train of thought interrupted, one more place you have to look to find a comment or note?

First, let’s take a look at the characteristics of the Yammer style of communication:

  1. It’s written (online)
  2. Very brief (about the size of an IM message)
  3. Can include attachments, but not common
  4. Visible to all in the enterprise (unless posted to private group)
  5. Messages can be tagged for organization/filtering by keywords
  6. Only your “followers” (or followers of a tag used) are “notified” – except for messages targeted at an individual, the author doesn’t choose the audience
  7. Mode of notification is configurable (from in-your-face to I’ll look it up when I remember)
  8. Messages are searchable by all

Twitter is billed as a microblog, where users post random thoughts and actions of the day (the form for posts asks you “What are you doing?”). The main benefit touted by users is that out of this chaos, you end up learning things about your friends you never knew. Yammer seems to be aiming for the same thing in a business setting (they ask “What are you working on?” in the desktop app. Online, they are more open-ended: “Share something with My Colleagues”). Unlike IMs and email, Twitter doesn’t seem to be for everyone; only those with a yen for connectivity really seem to grok it. In a business setting, particularly in a small company such as mine, it seems unlikely that we could achieve the critical mass necessary to make this work.

But there are some problems with communication out there in the corporate world that I have been looking to solve. The biggest issue I have is the need for a bottom-up “news from the trenches”-style way for developers to let me know what they do and I don’t. The types of things that may get mentioned at the water cooler and then forgotten; the fleeting idea that even the developer soon forgets; the magic shortcut command that only one guy in the corner is using; the little detail in the fine print of the new product we’re buying that means it’s not going to work with our software.

One would think that forums would work for this type of communication, but they don’t. Perhaps the problem is that there’s a certain sense of responsibility when you post to one: what if no one responds to my idea? What if people think it’s crap? A lot of people with really good ideas would rather remain anonymous than stick their necks out for what’s no more than a fleeting thought. But I think another part of the problem is just the sheer overhead involved in using forums: first you have to open the page, look to see if anyone’s posted something similar, create a new topic, write up some sort of backgroud story to fill up the big textarea… And who goes around browsing the forums for new posts, anyway?

Here’s where I think Twitter/Yammer-style communication may come in handy. It takes all of 10 seconds to post a single sentence, you can tag it so that it gets found by the people who care (#yammer #productivity hey! That chain icon on the plugin pastes a link to the current page), and there’s no expectation whatsoever that people will respond. The messages are searchable later, meaning that someone that wasn’t previously watching the tag could go and grab all the #productivity tips if they want to.

The other area I’m looking at is with project coordination and communication. An interesting thing that has evolved here at work is the use of Skype chats created specifically for members of a project team to coordinate their actions, ask questions, and so on. The one complaint I’ve heard about this approach is that people on the “outside” (not added to the chat) have no way of knowing what’s going on in the chat, and no way of looking at the history when they finally are. Yammer could be a solution to that problem, although it’s a terrible medium for active discussions.

So will it work? Will people use it freely, without putting a gun to their heads? Will it increase the sharing of knowledge at work and capture those important but elusive thoughts, or will it be just another icon on the desktop and another distraction from real work? I’m just starting to test it out here where I work, so I don’t have a conclusive answer yet, but I can make some initial observations.

First of all, It’s not a no-brainer. The best ideas catch on without any explanation, but with Yammer, people don’t seem to get it right away (me included). Twitter is the same way, so this doesn’t necessarily spell doom for this little experiment. Still, I sent out a general announcement to about 20 people, and got exactly 1 person who signed up (and since then hasn’t posted a single message). I next took the approach of asking people one at a time to join, explaining the basic concept to them in the process. While they seemed interested in the idea, I find I’m still pretty much the only one posting. Now I’m trying a 2-pronged approach of getting all the members of a small project to try it out for project-related communication, while encouraging developers to post some very specific ideas (around #productivity tips) when they have them.

I find that a few good examples help, and as I myself gain experience with it, I’m getting a feel for when to use it. Just today, I was in a meeting for one project, and had a quick thought about an unrelated subject. I grabbed my iPod and quickly “yammered” the idea out to the related tag. Too bad no one out there is listening…

So, perhaps this is an idea that will work, once people get used to it. Or perhaps Yammer’s value is no more that of Twitter: good for connecting the Web 2.0 addicts of your business in chaotic an unpredictable ways. Which is great for a fortune 500 enterprise, but sure feels lonely for us small guys.


Enterprise 2.0

August 27, 2008

It looks like I’ve been a little behind the curve on this “Enterprise 2.0” thing. I thought the term was just something Josh Street had made up as a whimsical way to tie his presentation together. It turns out it’s a term that is not only tossed about in tech discussions – there’s already a Wikipedia entry, a “movement”, and people grumbling about how everyone’s missing the whole point.

Well, I promise from now on to be more on top of things (“Be at the forefront”, after all). I finally got my “unread RSS entries” count down from 2000+ to a mere 50 or so.

I am glad to see that I wasn’t “missing the point” on this, since we have been using a lot of these technologies for some time. My “Architecture 2.0” series will continue (as my adaptation of Enterprise 2.0 to the practice of software architecture), and so will my efforts to find new ways to improve our collaboration and efficiency via tools. Stay tuned!


Documenting Architecture Decisions

August 25, 2008

Record Your Rationale

I just posted another axiom to the “97 Things” project called “Record your rationale”. The basic idea is that you should keep a record of why architectural decisions were made so that when someone asks, or when you’re thinking of changing your mind, it’s all there to remind you. This is a common problem, especially for architects who inherit someone else’s system: why this heck did they do THAT? Without a record of the rationale, inobvious solutions can seem like pure lunacy (or stupidity). I have actually caught myself voicing that sort of negative opinion out loud, right in the company of the very person that had done the implementation. Oops.

But I digress. I don’t want to spend this post rehashing what I wrote in the other site (if you’re interested, by all means go read it). I’d like to discuss how we’re recording our rationale at Sakonnet. First, let me post here a part of the original axiom that I cut out to reduce the number of details:

More formal approaches to this type of documentation involve using a standard template that includes the following information:

  • The name (or brief description) of the decision
  • A brief summary of the issue that the solution attempts to resolve
  • A description of the final solution that was selected
  • Factors that influenced the final decision (functional and non-functional requirements, technical, legal and other constraints, political factors (e.g. partnerships with software vendors), or just about anything else that was considered in the decision making process)
  • A prioritized list of quality attributes (is performance, security, cost or maintainability more important in this case?)
  • The final rationale behind the decision
  • A description of alternate solutions that were considered, and why they were rejected

Architecture Decisions

At Sakonnet, we are using a template, but not quite so formal as the one presented above. This is partly because I started out simple just to try out the concept, and partly because I didn’t want to create roadblocks or intimidate people from creating and using them.

I created something called “Architecture Decisions” (very original, right?), which consist basically of a summary (a title, often framed as a question: “How can we improve the monitorability of our message-driven processes?”), a more in-depth description of the problem (often accompanied by some alternatives that are being considered), and a “resolution” that gets filled out when the decision has been made and the issue is being closed. There are also fields for explaining “impacts on Quality of Service” as a consequence of the decision made. This is divided into four main categories (Performance, Scalability, Reliability, Maintainability), plus an “Others” field for anything else. These fields are all plain text.

Architecture 2.0

By now you’re probably picturing a stale templated Word document two pages long or so that gets lost in the file system, never gets properly filled out, and no one ever sees it or can ever find it again, right? This is where it gets interesting. Architecture Decisions are a key component of what I’m (unfortunately) calling (in this blog only) “Architecture 2.0”: an approach to the architecture process which leverages web 2.0-style application features and community to improve communication, participation and agility (especially with regards to documentation) (note that this isn’t my idea – I’m just borrowing it, including more or less the name, from a presentation called “Enterprise 2.0” recently given by Josh Street).

I created Architecture Decisions (ADs) as a new type of element in the web-based process tracking software that we’re using at Sakonnet. Think of it as a type of Jira or Bugzilla, only more generic and flexible (and less oriented towards software development…). In this system, I was able to define all the fields for these decisions, and more.

Lifecycle

Thanks to the web-based medium, I was able to define both a workflow and a lifecycle for these decisions. The workflow entails the following steps (statuses):

  1. Not started – the decision was created, but isn’t being actively looked at yet
  2. Being investigated – someone (or some group) is looking into the issues surrounding the decision. There is an “assigned to” field for ADs so that everyone can see who specifically is responsible for seeing it through to the end. There is also a “due date” for tracking and reminders.
  3. Decision made – the final solution has been chosen. At this point, the owner needs to fill out the Resolution and the Impacts on Quality of Service fields. People also get notified (more on this below).
  4. Work scheduled – you’ve made the decision, but you’re not done yet! The solution still needs to get implemented. So the AD only reaches this status when the owner has created any specs or tasks required to actually make the decision happen.
  5. Implemented – if the decision has been carried out and implemented in the system, you are now done. But the decision hasn’t reached the end of its lifecycle…
  • Others:
  • Cancelled – if the decision was created by mistake, or someone decided it wasn’t worth going through the motions
  • Deprecated – NOW the decision has really died. More on this below.

The life of an AD is something like the life of a bill (queue Schoolhouse Rock), but without the politics. Someone has a brilliant idea (or a problem), and they write it up in the web site. Then it stays open until someone finally gets around to making up their mind about it. Work gets scheduled, and if it’s important it gets assigned to someone and completed (otherwise, it may linger forever in the limbo known as the “pipeline”).

However, at any point after the decision is made, it may get replaced by a new decision. This may be due to a change in the context (performance suddenly got priority over maintainability), or because new information came to light (something like reopening a case due to “new evidence”). For example, if a decision was made because the middleware doesn’t provide a feature out-of-the-box, you may have to rethink things if a new version of the middleware is released. When the decision changes, a new AD is opened, and the old one is marked as “Deprecated”, meaning it’s no longer valid. A link should be provided to the new decision, but for now this isn’t automatic.

I’ve found from practice that there are a lot of times you want to make just a small change that doesn’t affect the spirit of the decision (e.g. in the solution, you mention an XML tag you want to call <foo>, but you later decide it should be called <Foo> – presumably that change isn’t going to make a big difference). We could just go and alter the text, but people might not notice the change, and it might get overlooked. In this case, I want to have a workflow called “Amendment”, where the AD can be altered slightly, and the change recorded in the history. We haven’t implemented that yet, but I’m working on it.

Collaboration

Documentation of rationale is an important historical artifact. However, for Architecture Decisions, I wanted more than this. Actually, the idea came about for two reasons:

  1. I realized that developers were placing technical discussions in the forum for the specs they were working on
  2. I realized that developers didn’t always know how or when to raise technical issues to the architects

So I created the ADs. They have a number of features which resolve these problems, and more. Like the specs, bugs, and so on, there is a discussion forum for each one. This ends up being type of “living documentation” of the discussion. The back and forth between people ends up looking something like the Federalist Papers (ok, I exaggerate), where you can actually see the proposals and reasoning behind them.

ADs can be associated with “deliverables” (something like a project, or a group of specs), specs and bugs. In fact, they can be CREATED from within any of these. This means that a developer can be given a spec, have questions about the best way to implement it, and with the hit of the button, they can ask the architects. Remember, the “summary” field is often phrased as a question: “Is it ok to use messaging to generate the Foo Report?”

Equally important, the ADs are hooked up to send email notifications at the right times:

  1. Whenever an AD is created, people are notified. This used to be just the architects, but since I want more contribution from the developers (“Empower developers!”), I recently added all developers to the mailing list. So far, no ones complained about the spam.
  2. Whever an AD is marked “Decision Made”, all develoepers receive the notification. This is a way to automatically communicate important decisions regarding the architecture. Since there are 35 developers on the team, it can be hard to make sure everyone got the message.
  3. Anyone working on the related item will get notified whenever someone posts a comment to the forum. Also, anyone that contributes an opinion of their own gets notified.

So far, all of this is working out remarkably well!

Finding Decisions

Another concern I mentioned in my “axiom” is that this information should all be searchable. If you have to spend more than 5 minutes looking for a past decision, you probably won’t do it. Fortunately, for ADs, all their text is searchable via the web interface!

I also went to the effort to provide some other methods to facilitate their use. First, I added the following fields:

  • Category – this is just a free-form plain text field where the architect can fill in a quick description of the “component” or piece of the system to which the decision relates. This was also my way to track exactly what kinds of components this would entail. We’ve got about 250 ADs in the system now, and a set of de facto categorizations have naturally evolved.
  • Functional component – it can be important to track exactly which sets of functionality are being affected by a decision (is this about credit notes replication? Trade saving?). If it affects everything (our Exception Handling Framework), this field is left blank. This field is a drop-down box of pre-defined options.
  • Non-functional component – this is another drop-down of options. It was nearly impossible to pick out a set of non-functional components and stick with it. I started with the “Categories” that people had created on their own. I tossed in some formal components, layers and other elements I’d defined in our official architecture documentation, and so on. The fact is that decisions can affect the software at just about any granularity, hierarchical or not. I’ll write up a separate post some time about categorization of ADs, because it’s a toughy.

So, you can search and sort based on any of the above fields. This can be really useful to answer questions like, “what were all the decisions we made regarding our JMS messaging framework?”

Our web application also lets you define and store reports for repeated use. So I have created a number of views (including things like “which decisions are still open, but due in the next week?”), but there is one that I find very fascinating: The Reigning Decisions Report. This report will show you all the decisions that are in the status “Decision Made”, “Work Scheduled” or “Implemented”. In other words, all the decisions that a developer needs to know at any time about the current system. What’s really cool about this one is that if a decision ever gets “deprecated”, it drops out of the view. If its replacement decision gets made, it shows up instead. This report is ordered and grouped by the Category field.

Parting Thoughts

I must admit that I had delusions about everyone being able to look at my reports and see the WHOLE ARCHITECTURE with a glance. Its one of those things that sounds fantastic in theory, but will never happen in practice. Not every decision made is recorded as an AD, even when they should be. I do my best to keep my eye out for changes that should be recorded this way, and people are generally good about doing so themselves, but sometimes things slip through the cracks. Also, the system was already 8 years old when we started doing this. It would be absurd to think that there is value in going back and documenting every old decision in this system.

Also, there are times when creating an AD for every decision made is too much of a burden to make sense. For big projects, there is usually some up-front design and analysis, during which a whole set of features may be discusssed. It would be impractical to separate each and every “decision” into its own AD, but I still want to record the rationale behind the design. For these cases, we instead create a brief “design document” that gets saved to our version control, and create a single AD which summarizes the design, and links to the actual document. In this way, history is preserved, the decisions are somewhat searchable, and we don’t waste a lot of time unnecessarily.

Architecture Decisions were simple to create, and are a fantastically easy way to “record our rationale”. More importantly, they enhance our ability to collaborate and to communicate architectural changes, standards and principles that would otherwise be discussed (and remain) behind closed doors. They turn out to be a great way to get developers (those that are interested) involved in the design process before these decisions are force-fed to them. In my opinion, they are a critical part of a successful “Archtecture 2.0” environment, and from now on they’re something I’ll never do without.


Wiki with Version

August 14, 2008

I’m looking for a wiki that has all the standard features, plus one more: integration with Subversion. By that, I don’t just mean it can spew calls to a command-line “svn” whenever you update a page. Sure, that’s a good start, and I hear rumors that TWiki has plugins that can be hacked to do that. What I really want is a full awareness of the branching features of Subversion… I want a Wiki with Version.

The idea here is to be able to use a wiki as the location of record for my application’s documentation. The problem is that my application is constantly being branched and versioned. A single set of documentation (architectural or otherwise) would have no way of capturing all the nuances and changes between versions, so we need to have a separate set of documentation for each. We already have a user guide up in a wiki for our customers, and I can assure you that it can be a nightmare to maintain the documentation for all releases. It basically comes down to a separate document tree for each release, with a lot of copy-paste between them. And with no automatic “merge” feature to speak of. At least with user docs, we only care about releases; for internal documentation, every branch could have unique information.

So, I’d like my wiki to actually store its data in Subversion. I’d like it to know what my project root is, and what branches are available. I’d like it to automatically produce a new “document tree” whenever a new branch is created. I’d also like to be able to merge pages across branches. If I can’t do it via the web interface, at least I’d like to be able to do it in Subversion and have it show up in the wiki.

This doesn’t sound like rocket science, but I haven’t found anyone that’s done it yet. There’s a project called SubWiki that looks inspired by the same idea, but it apparently never got off the ground. Maybe I’m looking for the wrong thing – is there a content management system that would do this better? If I don’t find something soon, I may have to start my own “WikiVN” project so that I don’t have to copy-paste things by hand. But I also don’t want to have to rewrite all the wiki functionality out there from scratch. How about a TWiki plugin?

Oh, one other must-have feature: in the name of canonicality, I’d like to be able to autogenerate official-looking Word Documents or PDFs from these pages. I suppose if they are in HTML files, I could hack it, but wouldn’t it be great just to get a list of the wiki pages, select the ones you want, order them, and *poof!* out comes the doc! I’ve had enough experience with this to know that web docs != PDFs without a lot of conscious thought and work, but if there’s user-friendly way to design different stylesheets, it could just work.