Manuel Klimek

Software is complicated. More often than not it's a complicated mess. Sometimes even a tangled complicated mess. And wherever you look all you see is tradeoffs. There are no easy solutions (tm). The dll hell is replaced by the side-by-side hell. Emacs is better than Vim, Vim is better than the Visual Studio editor and the Visual Studio editor is better than Emacs. The Visual Studio editor even has a kill-ring (Ctrl-Shift-Ins). But Emacs has a web-browser. Vim is way cooler because I can't remember the commands, even though they're orthogonal. To what? Why not write a new editor in Erlang. Well, no, not me, I just want an editor that has all the features of Emacs, Vim and Visual Studio. Now. But without the bloat of Emacs. Or Visual Studio. More slick, just like Vi.

Since the early days of computer science, when software developers still had to wear suits at work and wrote A.I.s in Cobol, um, COBOL, with their feet, people tried to find out how software development could be made less complicated. And they soon discovered that the secret sauce is abstraction.

Abstraction

Layers. Components. Modules. Interfaces. Design. Architecture. It's so easy: define an architecture, think of layers, interfaces, modules. Create a nice design that meets this architecture's goals. Hire a bunch of developers to implement the components.

From this level of abstraction it really sounds easy. This is why it's called abstraction: it hides the complicated details. The good thing is that as long as you work on this level of abstraction, it's cheap to change your concept. Or as Joel Spolsky says:

Designing a feature by writing a thoughtful spec takes about 1/10th as much time as writing the code for that feature—or less.

Well, than it's obviously a very good idea to do all the design first. After all, if you change your design, you'll have to change your implementation. As long as you didn't start writing code, changing your design is easy. Or even better, start at the architecture level. Hire the best consultants to create the perfect architecture. Hire some really bright guys to do your design. In the end, a bunch of monkeys can do the implementation. The dream of the pointy-haired boss came true!

"Um. Sounds easy. So, how do we know that our design is good?"
"This is easy: experience."
"But to get experience I'd have to actually try the design, won't I?"
"Yes, of course."

"So, if my design is not perfect in the first place, I'll learn this only when I try to implement it?"

"Well, yes, come to the point."

"Then how can I finish my design before the implementation phase?"

"Um. Well. You just do iterations. Big iterations, I guess, because design is so much easier to change."

"So I work for months on a design of which I don't even know that I will be able to implement it?"

"Perhaps... easier to. Um, change..."
"And when I finally find out that my design was crap, I'm in the implementation phase, a deadline looming on the horizon and no time to change the design and all the code that was already written?"
"... - well, is there a different way?"

Feedback

Tradeoffs again. Working with abstractions means to get less feedback. "I'll take the chair and hit the sentinel" will be a hard job if the chair turns out to weight a hundred pounds.

And feedback is important. One of the laws of software development is:
The longer it takes until you find out that you made an error, the more costly it is to fix that error.

This means that you should try to find your errors as quickly as possible. But when you're working on a high abstraction level, you just don't know all the complicated details because, well, that's why you're working on that high abstraction level, isn't it? So you'll find out that your design is crap when you're in the "implementation phase", at which point nobody has time to change the design. So you just live with the crappy design and run around cursing the designer and hating your job.

Fail!

One solution to discover your errors early, is to do Ultra Extreme Elite Programming (Joel Spolsky). Design just enough up front that you get an idea of where you're going, write the target down as a test and sit down with a colleague to find a redundancy-free implementation. When you find out that your initial design is crap, which you'll do very quickly, rely on your tests to help you refactor your code to a better design. Of course, as Joel puts it so beautifully, this is like driving around with the handbrakes on.

The question is whether driving around with the handbrakes on is really slower than driving at full speed with closed eyes and a plan. I think it mostly depends on where you want to end.

Today after our planning game I did a short poll on how the guys perceive test driven development and pair programming. We're trying to do both for some time now, and since I take the blame for introducing both practices, I feel I'm somewhat - um - preoccupied on that matter. A few days ago, I was caught totally off guard when Richard told me that, well, he doesn't believe programming in pairs is more productive. Bummer. And I had believed my show to be grand circus.
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Steve McConnell responds to Eric Wise's article Rejecting Software Engineering that Rumors of Software Engineering's Death are Greatly Exaggerated". There's a lot of fuzz about the usage of the word "engineering" when it comes to software development. What's this all about?

What is engineering?

According to wikipedia, engineering is defined by the ECPD as

The creative application of scientific principles to design or develop structures, machines, apparatus, or manufacturing processes, or works utilizing them singly or in combination; or to construct or operate the same with full cognizance of their design; or to forecast their behavior under specific operating conditions; all as respects an intended function, economics of operation and safety to life and property.

When I look at this definition I don't really see anything that would not be applicable to software development. Steve McConnell generously points out that software engineering is recognized and practiced for some time now, so where does this new-fashioned stubborn refusal to call the child by it's name come from?

The engineering process

The real problem comes to light when you look at the engineering process. You'll find a description of the engineering process on wikipedia. The article describes the engineering process in four stages:

• Conceive
• Design
• Realize
• Service

Now there are some engineers who map the engineering stages to software development in a rather funny way: They think that "Design" is the process of drawing good looking UML diagrams and that "Realize" is "Coding". When you look at the wikipedia article, you'll see that for engineers "Realize" stands for "Manufacturing". In a software context, manufacturing means running the compiler and pressing some CDs or deploying some binary over the Internet.

So when engineers claim that software developers should look at how engineers do their design and all this talk about software processes would be settled once and for all, they're ignoring that software development is a design-only activity and that software has a lot less problems with the "Realization" stage than traditional engineering.

When a software developer writes code she is building an executable, mathematical model of reality.

Conclusion

When software developers prefer not to use the title "engineer" to describe what they're doing, they're trying to avoid a mapping of the engineering process onto the software development process that is wrong. In the end, software developers will build mathematical models (source code) and apply scientific methods (complexity analysis) to solve problems. If this is not engineering, than we're not engineers.

Are you a developer who dreams about a better software development process in the organization you work for? Maybe you read something about fancy practices on your favorite blog or mayhap you even touched one of those old-style paper collections called books? Do you have some concrete ideas on how to improve, but don't know how to start? I was in the same situation a year ago. Here's what I did and what I would do differently today.

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When I arrived at work today I fired up Outlook and checked my mail. I found five mails from our auto-build server telling me that the build broke. Since we introduced test driven development and continuous integration only a short time ago this was not out of nowhere - the build usually breaks at least once a day.

But today was the first day a unit test broke since we introduced TDD and CI.
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A month ago I bought a TREKSTOR NDAS device. This devices promises on it's package to be linux compatible. So after I unpacked the hardware and everything was running in Windows I tried to install it in linux. Unfortunately the stock feisty debian package I found didn't work with my WLAN configuration.

Now after I reinstalled ubuntu and upgraded to gutsy which comes right now with a 2.6.22er kernel I tried to build the driver from source. I had to patch the sources to make it work, but since it works flawlessly right now I provide my patch and a little compilation howto.

Download the current NDAS sources and my NDAS patch for linux kernel 2.6.22.

# installed some packages. I don't know which exactly, but you'll need
# at least the following:
apt-get install build-essential checkinstall linux-headers-generic

# extract and patch the ndas sources...
tar xvzf /path/to/ndas-1.1-2.tar.gz
cd ndas-1.1-2
patch -p1 < /path/to/ndas-1.1-2_kernel-2.22.patch

# you only need to set NDAS_KERNEL_VERSION if you
# don't want to compile ndas for the currently running
# kernel for example, if you're compling from within colinux
NDAS_KERNEL_VERSION=2.6.22-6-generic
make

# ndas_root must be exported for make install and
# checkinstall to work
export ndas_root=$(pwd)
# somehow I had to make install before checkinstall...
# this is no problem, since checkinstall will clean up
# the whole mess again
sudo make install
sudo checkinstall

After that you can start the NDAS service by issuing

/etc/init.d/ndas start

Configure your device by following the Ximeta NDAS driver documentation.

My Vista Home Premium finally arrived. Since I have a Ati 9250 at work, which is a smartly rebranded DirectX 8 card, I was craving for the full "vista experience". After doing some backup I installed Vista on my laptop and spent some time setting up the basic programs I need. Since installing colinux is one of the great challenges of the Game Of Windows I'll try to present you a step-by-step guide to a working mobile colinux setup in Vista.
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There is a single most important rule to IT security:

Always address the weakest link.

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Do you estimate the time it will take you to finish your task in the mythical unit called "perfect engineering day"? Have you ever wondered why?
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The first human beings had a hard time. When they weren't on edge due to the Neanderthals who constantly tried to get their unprofitable genes into the big pool again, they had to deal with a real challenge: self reflection.

When I exercise my introspectional skills I often think fondly of my ancestors. I imagine their first grunted discussions of values, time and the meaning of soccer. And I believe these discussions closely resembled those we see about good code nowadays. But without the discussion we'd probably still be fighting naked over the affection of women. Um...

In this article I'll try to define good code from a business value perspective. I'll come to this conclusion:
Good Code executes a set of features correctly in a specified time (present value) and maximizes future value (minimizes future cost) by adhering to the dynamic nature of code through an ROI-oriented design, a test suite, process automation and VCS-usage.

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