Charles Penn
Charles Penn
Senior Test Engineer
He/Him/His
Software tester in the Midwest of the US.
Typically happy to discuss testing of any sort, geeky things, and parenting.
馃巶 MoTaBirthday | September 26, 2017
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On the 15th of January 2026 myself and Ujjwal Kumar Singh joined a call and pressed record. We were curious to see what would happen. A few weeks later I鈥檇 done the same with Neil Taylor and Clare ...
6 Jul
Charles Penn asks:
What helps you stay disciplined about performing exploratory testing regularly? I know that I can get caught up in other work and fail to take the time to do exploratory testing....
19 Mar
Charles Penn asked
What resources do you use to decide what is most vital when you start advocating for Accessibility in an application? What resources do you use when you start testing for A...
17 Mar
System testing is often seen as just the top of the Automation Pyramid, which can lead it to being minimized to a dangerous point.This has been my focus during my career, and I am always happy to ...
17 Mar
If you didn't write it, do you own it? The role of AI Guardrails in code quality.
27 Apr
AI guardrails: Non-negotiable safety or overly cautious "slowdowns"?
18 Feb
Learn how to survive and adapt as a solo test lead on a large, long-running project.
11 May
Master the core functionalities and practical implementation of TestComplete through a hands-on demonstration of UI automation, object mapping, and CI/CD integration for desktop applications.
31 Mar
Comments
(7)
AMA about System Testing
Simon,
I've experimented with this a few times!
Currently, I am in favor of the Round Earth Test Strategy found here: https://www.satisfice.com/blog/archives/4947
I've been toying with the idea of modeling it after a hot air balloon, but I might be trying to be too cute with it.
AMA about System Testing
Ady,
I define system testing as any testing that exercises the application under test as a user in order to verify that it works properly.
A system is any piece of software a user interacts with. (note that this doesn't always mean the user is a human. You can have other pieces of software that interact with your software. Those are users too!)
Good idea to add it, before I do, any thoughts on my definition?
AMA about System Testing
(Cont.)
If you build up system level tests, you can update the code underneath with more confidence (and build up your other levels of testing while you're at it!).
We've actually seen this situation at our company already, and I can imagine a lot of Vibe Coded applications exacerbating this.
On the other hand, using agentic tools, we've started finding ways to build some of our system level testing faster, and with guardrails to make us confident in what is actually changing.
AMA about System Testing
Rosie,
You could certainly argue (and I would) that Systems Testing is going to stay at least as important, if not more so in the age of AI.
One example I can think of is if you're brought in to work on an existing system that was heavily written using AI.
The code base may not have sufficient coverage at the unit or integration levels, which can cause some real concern when trying to make changes or refactor.
AMA about System Testing
Hello all!
I'm sorry for the delay, I actually thought I'd get an email for responses. Simon pinged me to let me know I was missing all of your questions.
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The Four Pillars of Observability
I'm keeping myself accountable by sharing my observability learnings, starting with the four pillars of observability.
What is observability?When something goes wrong in a software system, you nee...
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