Guy Davis - Software Developer/Programmer

House now fully framed

Progress on our house is going well. The builder has now completed the framing stage, including all windows and doors. The plumber has even started laying the PEX tubing into the Warmboard radiant-heated sub-floor. Now they'll turn their attention to the electrical, plumbing, and other mechanical systems.

Release Planning based on Team Velocity

Due to a recent shake-up at work, I've been asked to handle release planning for our software product. Up to now, I've been primarily concerned with iteration planning for our two-week sprints. Release planning covers a wider scope of up to a year in our case. So I was handed a MS Excel spreadsheet which held the release plan from our previous manager. I was a bit surprised by what I found.

First some history. Our team follows a Scrum process using the XPlanner web app for tracking (shown on right). We've done this for a number of years now and it has worked well for us. Key steps in this process for us:

Entire team estimates using planning poker. This gives better task estimates which the team feels committed to achieving.
We learn from our successes and failures by holding sprint retrospectives. This helps improve our estimates going forward.
We use our project velocity to guide our workload for the next iteration.

Considering our commitment to Agile software development, I was surprised to see the release plan spreadsheet consisted of:

New features (user stories) estimated by the manager in terms of days of effort required.
A static resource analysis that assumes project velocity is simply number of hours in the office, discounted by a factor of 0.7.
Finally, the spreadsheet didn't actually prioritize every story in a single list. It just grouped them into quarters, within which no priority was given.

This traditional analysis is flawed in a few key ways:

Since the team didn't have input on the story estimates, they feel they don't have control over the process and are not committed to the goal of accomplishing the work in the estimated time.
By planning release milestones using a theoretical resource calculation, the release plan ignores a key team metric: project velocity. Project velocity is the number of story points completed in an iteration. When normalized to 100% team strength, this velocity number can be used to predict how many prioritized stories can be completed in the coming sprints.

Since a key function of the product backlog is to provide a total ordering of the stories by priority, I've moved the product backlog out of the spreadsheet and into XPlanner. We're now using our project velocity to determine which stories will be completed in which milestone. Finally, I've started getting story estimates from the entire team.

Should upper management still require burn up charts in spreadsheets for reporting, I'll generate them periodically from XPlanner. Hopefully, this more realistic approach will begin to improve our release process, resulting in better software releases in the future.

Note: Since XPlanner is a dead product, we're considering alternatives, but it works for now. As well, we're currently estimating both the sprint backlog and product backlog in ideal time. I'd like to adopt Mike Cohn's approach of using different units (story points) for the product backlog soon.

Posted by Guy | Posted on 2010-02-21 at 1:52 PM | Comments (View)

Geo-exchange holes being drilled

The house is progressing nicely. This week a drilling crew was on-site to drill four geo-exchange holes to a depth of 250 feet each. By pumping water (with bit of anti-freeze) through PEX tubing loops left behind, our geo-exchange system will be able to gather heat from the earth. This free heat results in a very efficient heat source for our radiant in-floor heating.

Main Floor coming together

Now that the weather has warmed and the xmas holidays are over, work is progressing on our house again. The workmen have installed the main floor joists, laid the WarmBoard sub-floor, and are beginning to erect the polyurethane structural-insulated panels (SIPs).

Apparently, installing the Warmboard is just as easy as a plain OSB sub-floor except you need to lay the sheets into the overall pattern set at the factory. This allows all the grooves in the aluminum to line up for the PEX tubing for the in-floor heat.

Leaving Facebook

A number of years ago, I signed up for a Facebook account, tightened down all the privacy settings so I was nearly invisible, then promptly forgot about it. A month or so ago, Facebook loosened some of their settings so I started getting "Friend" requests. Since I have a public website and use Twitter I'm not exactly trying to hide online, so I accepted the Facebook requests.

The Facebook "friends" where, almost exclusively, people I went to high-school with. Initially, it was interesting to see that X had grown up, moved to Y, and had two kids. However, rapidly I started getting inundated with friend requests from people I'd only known in passing during high-school.

As well, the status updates on Facebook were all boring personal stuff that I ignore on Twitter. However, on Facebook, I couldn't tune out the useless status updates like I do with Tweetdeck. To avoid the time-waste that is Facebook, I've deactivated my account. It just didn't fit into my online or real-world lives.

So I think I'll stick to useful services and practices for keeping in touch with people:

Meeting in real-life: I am still close friends with a handful of classmates who I see regularly for dinner, etc. Being in "online" touch with someone I shared a single class with and never talked with, doesn't seem useful to me.
LinkedIn: I do see the value in professional networking so I stay in touch with university classmates and past co-workers using a social network designed for professionals. No silly Pirate apps or 'Pokes' here.
Twitter: While Twitter might seem to be the peak of inane chatter, it's really much more powerful than that. As a means of connecting with anyone around the world interested in the same topics I'm interested in, Twitter is unsurpassed.

I find that I follow topics on Twitter (hashtags) much more than I follow individuals. For example, on Facebook I'd read how someone from my grade 10 class took a vacation to Saskatchewan. However, on Twitter I can follow anyone who is vacationing in Belize, where I'd like to visit one day. The key is that what is being shared is more interesting to me than who is sharing it.

I'm sure this preference has to do with my introverted personality which values information over personal connections. My sister is an extrovert and loves Facebook. To each their own. From now on though, you can find me on Twitter, but don't bother looking for me on Facebook.

Posted by Guy | Posted on 2010-01-14 at 1:23 PM | Comments (View)

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