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Exercise is the key to craftsmanship

How can you become better in what you are doing? The answer is simple; through exercise! This idea is practised a lot in software development through the usage of CodeKatas.

But CodeKatas suffer from their size. They are very small but this small size limits the methods, techniques, technologies that can be applied. To improve your TDD skills doing CodeKatas might be enough. But what about other skills? Developing on a software in a team, designing larger pieces of software, iteratively releasing software… all this and more is kinda hard to train using the tiny CodeKata problems.

Ralf Westphal introduces a new kind of exercise called Application Kata (or just AppKata).

“AppKatas are larger programming problems. They require the development of “whole” applications, i.e. not just one class or method, but bunches of classes accessible through a user interface. Also AppKata problems always are split into iterations. To get the most out of them, just look at the requirements of one iteration at a time. This way you´re closer to reality where requirements evolve in unexpected ways.”

So if you´re looking for more of a challenge for your software development skills, you can start with the following sample AppKatas that Ralf put on his blog:

CSV Viewer

An application to view CSV files. Sounds easy, but watch out! Requirements sometimes drastically change if the customer is happy with what you delivered.

Questionnaire

If you like GUI programming, this AppKata might be for you. It´s about an app to let people fill out questionnaires. Also this problem might be interestin for you, if you´re into DDD.

  • Iteration 1
  • Iteration 2 (to come)
  • Iteration 3 (to come)
  • Iteration 4 (to come)

Tic Tac Toe

For developers who like game programming. Although Tic Tac Toe is a trivial game, this AppKata poses some interesting infrastructure challenges. The GUI, however, stays simple; leave any 3D ambitions at home ;-)

  • Iteration 1
  • Iteration 2 (to come)
  • Iteration 3 (to come)
  • Iteration 4 (to come)
  • Iteration 5 (to come)
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