Ramblings of a software developer with a degree in bioinformatics. Agile development mixed with DNA sequencing - what could go wrong?
Monday, April 18, 2005
Book review: Laws of our Fathers, Scott Turow
Maybe the reason I like this sort of book is because of how little I relate. I've done quite a bit of studying of my family history, at least the Fulton and Alspach families, and as far as I can tell they were upstanding and sensible to a man; leading directly to my upstanding and sensible father, and leaving me with no particular emotional baggage, or at least no more than anyone else. We've no horse thieves, we've no child molestors. Maybe we're just really good at concealing it.
But of course we're all blind to our own character flaws. Maybe the rest of the world looks at my family and sees...what? Arrogance? Pomposity? Pretension? It's hard to say. Of course, for the most part no one thinks of anyone else at all, preferring to concentrate on what other people think of them.
Well, but so on the characters go, slaves to their various family pasts. The book twists and turns but holds together somehow, over the course of its 800 pages. I had trouble concentrating on some of the 60's bits, since I had picked it up looking for a courtroom. But worth a read if you have time. Lots of inner-city gang characterizations, so skip it if naughty words disturb you.
Sunday, April 17, 2005
Vacation Bible School ramping up
Friday, April 15, 2005
Finishing an agile project
Most clients will want to specify the items I gave up front: time, scope, and cost. But specifying all three variables will, almost invariably, lead to overruns, bugs, and dissatisfied customers. Why? Because software is inherently an abstraction. If I want to build a skyscraper, I can get an architect, draw some pictures, do a 3D model. I'll have a pretty good idea of what the concrete implementation of the skyscraper will be before the first shovelful of dirt is ever turned over. But software doesn't work that way. By the time you've put together a decent picture of what the software will look like, you're well on the way down the road and have probably put a pretty nice chunk of change into it. Now, you can try specifying time/scope/cost, maybe even do a good job of implementing it. But chances are if you've done that, you've told the clients you can't make that little change they wanted without changing the contract, updating the design, and of course, charging a lot more money. Now everyone's unhappy. The clients didn't get the change they wanted, so they're not as excited about your product. You're unhappy - or you should be - because you have an unhappy customer and a product that isn't as good as it could be.
So here's the solution: Rather than allowing quality to be the dependent variable, hold it constant and let another variable, say scope, be dependent instead. So now, you've got a contract that says you will work on this project for x number of months, and it will cost y dollars per month, and for that money, the client can choose whatever features they want next at the end of the month. Or, to put it another way, get rid of the deadline.
Whew, I think I'm either going to have to stop this series, or write a book. Next time, I'll finally come back to my church application.
Tuesday, April 12, 2005
Problems of Software Development 3
"We don't have the manpower to test the whole project every two weeks!"
Ah, but you've been writing unit tests all along, right? If your application has a solid set of unit tests, and every one of them pass, then you have a pretty good feeling that even if the new functionality you've added isn't quite right, you've probably not made anything worse for the existing customers. Besides, on big, complicated applications there's usually a process for getting new, isolated fixes out the door long before the next release comes out six months or a year down the road. What these fixes come down to are sort of a "Frequent Iterations" emergency measure - that is, the company doesn't believe in releasing software very often, but the customers insist upon it, so out the door it goes, sometimes whether it's been adequately tested or not.
Finally, automated acceptance tests are a key feature here as well. Unit tests are great, but they work at a deep level of the application. When it comes down to it, the user is going to need to click some buttons and type in some data, and is going to get an expected result. But there's no reason for a person to be doing work that computer is able to do, even if the computer has to move its own mouse and type on its own keyboard.
"Our users are going to file hundreds of change requests! The developers will be buried!"
But you've got a Customer, right?
I think the word Customer in the Extreme Programming sense is really poorly named. Everywhere you read about someone attempting this practice, they say, "Oh, but we don't do that. We have shrink-wrapped software." Or, "We have a dozen customers." This misses the point. Customer, as defined in the XP sense, is required to be a single person, or at the very least a committee. Whether the person speaks for one, a dozen, or 100 million actual customers is beside the point. The customer is responsible for looking at all the change requests, putting them into a neat order, and getting them to the programmers, who will be able to estimate a date based on the highest priority items.
"How will we ever know when it's done if we don't have the requirements set in stone up front?"
But what requirements were set in stone? Generally, they involve three factors; the project's:
- Time allotted
- Budget
- Scope
It neglects the simple fact that a project actually consists of four factors: the three above, plus quality. However, only three of these factors are independent; the fourth one will depend on the others. So, if you specify a project's Time, Scope, and Cost, you have fundamentally specified its Quality as well, and the only way to raise the quality is to lengthen the time, increase the cost, or reduce the scope.
So how do you know when the project is done. I'll look at that next.
Sunday, April 10, 2005
Xanga and RSS
http://www.xanga.com/rss.aspx?user=amy_gs_reading
http://www.ephemeraleuphoria.com/xanga/rss.php?amy_gs_reading
http://www.joshstaiger.org/XangaRssFixer.pl?user=amy_gs_reading
http://www.mikexstudios.com/labs/XangaRssFixer.php?user=amy_gs_reading
http://www.jasontan.org/xanga/rss.php?users=amy_gs_readings
http://www.acr-web.com/xangafeed.php?friend=amy_gs_readings
How many of these give back RSS that can be read in RSS Bandit? Well, that would be: One (1), the one from MikeXStudios. Thanks to the External Mind for that.
Friday, April 08, 2005
Agile in the trenches
Ron Jeffries. Martin Fowler.
Duh. Who does it that's never met either of those two people? Who's actually doing this down in the trenches to develop real software applications? Most importantly, who's never met these two people, develops real software applications with agility, and has a blog?
Me, I guess. But here's a few others:
http://pab-data.blogspot.com
http://tedogrady.blogspot.com
http://hhroark.blogspot.com/
http://geekswithblogs.net/sbellware
http://theagiledeveloper.com/default.aspx
http://www.undefined.com/ia
Importance of the church web site
Problems of Software Development 2
So what can be done? The basic problems I see here are #1: The Deadline, and #2: The Database. The programmers work in a panicky rush to fulfill all the items in the Database before the Deadline. So let's start with the obvious: Get rid of the deadline.
"Say what?" I hear you cry. "We can't just never release the project!" No, I'm not saying that. I'm saying - and this is one of the requirements of agility - release early and release often. Get the application into the hands of the users and let them bang on it. They may not find all the really picky little bugs, but that's OK for 99% of the users who won't ever use that functionality anyway. More importantly, the users are going to find the things like the button on the wrong form that would save each user four clicks if you just moved it. They'll find the missing report that they didn't know they needed until they saw how useful it would be with this application. Get the application out there quick enough to catch those things - and then fix them in the next release! How often? Every two weeks, I hear, is pretty reasonable.
But the objections now come thick and fast. "We don't have the manpower to test all the whole program every two weeks!" "Our users are going to file hundreds of change requests! The developers will be buried!" "How will we ever know when it's done if we don't have the requirements set in stone up front?" I'm not the greatest practitioner of agile methods in the world. But what I have found is that for every objection that someone makes to an agile idea, there's a pretty good response from the agiliots. I'll try to come up with responses to these next time. Oh, and I've even been working on an application! I'll try to get up to date on that as well.
Wednesday, April 06, 2005
Big visible belly
Problems of Software Development
Now, for the most part programmers are good people. They're interested in the project; they want to do a good job and make something easy and fun to use. So what goes wrong? Why do most applications ship with glaring bugs and obvious usability issues?
Here's why: Everything starts to revolve around this work unit database. Near the end, emails go out to the programmers saying, "I see you still have six work units left. Will you be able to get all those finished by Friday?" As the project moves forward, additional work units are added for new features or bugs. More emails go out. Eventually the project gets thrown to a tester, who enters dozens more work units. The programmers, faced with a long laundry list of items and a deadline, starts to cut corners. "OK, this item says we need to add a State Last Worked In field to the form. I know we're eventually going to need a Zip Code too, but I don't have time to worry about that; I have 15 more units to finish by Friday!" So the program goes without the zip code field. It goes back to the testers, who look at the list of completed work items; yup, there's the State Last Worked In field, looks good. Nobody's told the testers exactly what the purpose of the application is, so they don't know that a zip code needs to be there. Finally, all the laundry lists are complete, the testers sign off on it, the application ships. And customers look at it, scratch their heads, and say, "Why on earth didn't anyone think to put a zip code on that form?"
So what can be done to break this cycle? Well, the various methodologies that call themselves Agile have some ideas.
Tuesday, April 05, 2005
Buying some oil tankers
Sunday, April 03, 2005
What did we do that worked?
Great questions. Our service wasn't a whole lot different for Easter than it was for other weeks, but all I have to do is look at this week's service to get a mountain of ideas.
Why don't I keep a camera with me every week? We planted a tree in memory of a passed congregant after service. There were some cameras there, at least. I'll hope to get some pictures for the website.
Our service recording/archiving plan needs work. I didn't bring home the cassette tape with me, for copying to CD.
We got some brand new cubbies for the nursery. That should be handy, although volunteers are needed less in the nursery now that we have a paid worker again.
What did you do that worked? What did you do that didn't work?
Church management software part 3: Creeping feature
So right now, we're looking at three main pieces of the application: benevolence; attendance; and updating (wonder if I can come up with a word that means "updating" that ends in "ence", that would be cool). For ease of updates, we'll split these out into several assemblies:
- A stub. This will be the launcher application. It will be very simple and hopefully will allow us to update the other pieces very simply.
- A Benevolence assembly.
- An Attendance assembly.
- An Updates assembly.
- A Persistence assembly. This will handle the interface to the data store. Now I really need another word for "Updateance"!
Next step: We'll throw a few screens together and see how they look.
Friday, April 01, 2005
I still don't get Technorati
Reality Distortions: The Beginning
Very nice. Seems like an interesting guy. But this post was done four days ago. Why does technorati say it was two hours ago? Was there a format update? I don't get it. DLux, drop me a note if you want to talk about software for churches though :)
Church management software Part 2: Inherent requirements
#1: Security. We're talking about entering some very private information into a database here; not only are we talking about requests for charity, but personal data like social security numbers will be a likely requirement. Right now, the list of people to whom this information is available consists of: (a) the pastor, and (b) the deacons, and the file is kept locked in the pastor's office. So, while the ideal design would be a distributed one, keeping an online database behind a firewall and accessing it through a web service, I don't feel like I can guarantee the necessary security; even if I could talk all the users into keeping a nice strong password. So, for the initial pass, the data will be kept in local files on the computer. Presumably, when it is actually deployed, it will run on a single password-protected computer. I have some thoughts about using Windows Users and Groups to handle Role issues.
#2: Integrity. An important requirement for a church, huh? But specifically, I mean that the data shouldn't be corrupted; or at a minimum, regular backups should be arranged. The target audience for this project is a small church, and it's a pretty good bet that they won't be doing nightly tape backups of their systems. So at a minimum, regular backups should be done like Microsoft Word does, every minute or so; but ideally there would be a way to automatically back up to a different machine.
#3. Updatability. This is an agile requirement, really. I want to make the software very easy to update so that users will be encouraged to use the latest software at all times. This is a huge benefit for software developers. There's nothing worse than trying to figure out an issue based on a user who's running code from two releases, three service packs, and a hotfix ago. If people come to me for support, my first question will be, "Are you running the latest code? No? Update, and call me back if it's still happening."
Another agile requirement is that you avoid overdesigning the aplication. So, it's past time to write some code. One concept that really appeals to me is "Release 0". That's where you get an application out there that doesn't do anything at all except know how to update itself. Let's see if we can do that next.
Thursday, March 31, 2005
Church management software
So my church is looking for a better way to handle benevolence requests. These are requests that come in from people who need charity - say, $100 for fuel in the winter, or help with gas to visit a sick mother. I was casting about for things I might do as a Micro-ISV, so I thought I might be able to help out - and perhaps, if it works out well for this one church, be able to sell the application to others as well. That's a bit of a ways off, though.
So I'm tackling this project; more or less on my own as far as the design goes. I don't think my "customers" are going to be too demanding, so I'll have to keep on top of them to make sure that the application is actually useful to them. I'll be creating the design and requirements, etc., myself, so I think this is a good application to use some agile methodologies on. Specifically, this project will have: Test-driven development, frequent iterations, and easy updates.
So what are the requirements? If I ask the pastor, I'll get an easy answer: A way to enter benevolence requests online, without paper forms. A surprising addition, to my mind, is: A way to track down resources that might be able to fulfill a request. What this is, basically, is an algorithm for finding places that will take vouchers for gas; maybe food banks that could help a hungry person, etc. To my mind, these are such different goals that I'll just be ignoring this one, until I get further along in the development. So I'll concentrate first on the paperless form.
So the next question is, as a techie, what requirements do I see that underlie this prime requirement?
- A backing store
- Data entry screens
- Reports
Seem to be the minimum. I'll think about how I'll be fulfilling these requirements next time.
Tuesday, March 29, 2005
Writing again
There's some similarities between blogging and Extreme Programming, I think. They both rely on a tight and fast feedback loop. They both support rapid and easy change. They stress communication as a core value. And maybe most importantly, they both require a lot of discipline. It's easy to write code, hard to remember to write a test every time I make change. It's easy to start a blog, hard to remember to keep it going and keep it interesting.
So maybe this is my latest attempt to regain the discipline. I'll try to write some interesting things. We'll see if it works :)
Friday, December 03, 2004
Ballet Review: Nutcracker
Highlights: The Arabian Dance, Mother Ginger, and Damian Woetzel as the Cavalier. I thought his solos were an impressive display of leg strength. He's from the New York City Ballet. His duets with Julie Kent were good too. Mother Ginger is played by the same person (Colin Donnell) every year and he's utterly hilarious, camping up the role and bumping and grinding his 20-foot wide hips. Joshoa Sutton and Angelina Sansone did a very erotic Arabian Dance. They play a snake and a snake charmer, and she spends her time mostly crawling up and down his body. You could just feel the steam coming off them. I mentioned it to my wife, and she said, "Oh, the one two years ago was hotter." Guess I was still too sleep-deprived then.
Lowlights: The Prince didn't quite make it under Father Christmas's robe. You could see him running along behind, and that effect didn't work at all. I've thought the last few years that the magician (Theodore Keener) kind of gets short shrift. You can see the intent in what they're doing, to make him look mysterious and magical, but the timing always seems to be just far enough off that you don't get the impression of a puppetmaster pulling the strings of the other characters that they're going for. We thought the choreography in the Dance of the Snowflakes was slightly off.
In general: Fritz (Justin Zuschlag) was very effective, hassling the girls, swordfighting the magician, and sticking his tongue out at him when he thought he could get away with it. I wasn't that excited with any of the marionettes, which is a bit odd, because Joshoa Sutton played the Moor, and he also played the Mouse King and the snake charmer very effectively. They've redone the Chinese dance recently. I dunno; the dancers were very good, but I think I still preferred the dragon from last year. The Russian dance is my favorite to watch, it just pulses with energy. There was a baby on stage for the party scene. The lady next to me said it was Ms. Kent's, which is why she didn't perform last year. Having a baby must be one of the worst things a professional dancer can go through.
Here's what I found most odd: I think they were lacking a dancer. Not that they were lacking any of the parts, but the sequence at the beginning of the second act where the prince narrates the battle with the Mouse King, is supposed to be narrated TO someone - and no one was there! They told it all to themselves, just a little narcissistic reminiscence. I also thought that Julie Kent played the Dew Drop Fairy, but now that I check my program I see that's wrong; unless maybe that dancer was the missing one and Ms. Kent took over for her.
It seemed short to me this year, but maybe that's the sleep deprivation again. I can't imagine what they would have bothered to cut. We were home by 10:30. It plays twice tomorrow and once again on Sunday. See it if you have a chance!
Wednesday, December 01, 2004
IU loses to UNC 70-63
What I know: IU couldn't shoot to save their lives, and I don't think Carolina was much better. So why can't they shoot? The announcers say, "They don't translate what they learn in practice into games". The fans say, "They have a lousy coach." I think it could go either way. Coach Davis' first really good recruits were Marshall Strickland and Bracey Wright, and as one Peegs poster pointed out, neither one is any better as a junior than they were as freshmen. Coach's fault, or players? We won't know until - or perhaps unless - we get to see him coach a few more recruits.
What else I know: I love the freshmen! They're out there hustling and working, and Vaden nailed three three-pointers in the last couple of minutes. That's a great sign. But, so ends the first game against a really tough non-conference stretch. We'll see if the team gels...or perhaps just learns to shoot.