Stephan Kämper

Professionally, I test & write software as as self-employed software person. So far the businesses th...  
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Sep 22, 2021
Sep 22, 2021
Contributed to Open Source Project
My first contribution to got accepted: An improvement of some tests which are now using `assert_in_delta` for floating point numbers instead of `assert_equals`.

I noticed that there is an issue because a student I was mentoring had to round the result of a multiplication to make the tests pass, while my one solution didn't need this. For that particular exercise no solution should need rounding.

Remarkable: The only difference was the order of the operands in a rather simple multiplication: `x * y * z` resulted in a slightly different number than `y * x * z`.

Take care when processing flotation point numbers.
Aug 06, 2021
Aug 06, 2021
Update book
Started updating my ebook 'Fast Feedback Using Ruby' (see… again.

It's still amazing how fast software versions and thus the software behaviour changes.

I already found some interesting changes how some of the tools have changes since their last release (with a minor version change).
Aug 06, 2021
Aug 06, 2021
Joined a Beta Test
Nice: Joined the TestFlight for Polywork's iOS app. 😀
Jul 02, 2021
Jul 02, 2021
Contributed to open source
Yay, I'm a Cucumber committer!


Feb 01, 2020
Feb 01, 2020
Started a new role at hannover re
Excited to join hannover re as Software Tester! 🎉
Software Tester, hannover re


Nov 04, 2019
Nov 04, 2019
Delivered a keynote
I gave a keynote "Being Lucky" at the Agile Testing Days 2019, in Potsdam Germany A summary of the talk is available at

It ended up as one of the top-ten sessions at the conference: — and one of the few that received standing ovations.
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