Posts by ALbert Mietus

Agile System Architecting

There always has been some anarchy about the architect’s role –and even more distraction when we combine it with software and/or system. I’m not going to solve that. Not today …

Read more ...


Applying BDD & TDD in legacy

reading-time:

8m45

As I described in Introducing BDD & TDD, understanding the common goals of Behavior & Test Driven Development and defining your specific needs is the first and most critical step to start using this essential discipline.
Whenever the goal is to use new tools, it is simple: purchase them, shop for some hands-on training, and you are done.

Our ambition is different: we want to become Agile and Lean.
Then, it depends on the starting point too. B&TDD in greenfield development is relatively simple: start writing your tests and code!

However, starting with B&TDD in (Modern) Embedded Software can be more challenging due to the existing and often extensive codebase that was developed before the emergence of B&TDD.
Then, the question ‘How to start?’ is more like ’How to get out of the waterfall?’

Read more ...


Introducing BDD & TDD

reading-time:

5m30

Is Behavior & Test Driven Development an essential aspect of professional software engineering? Leaders such as #UncleBob compare it to ‘double entry bookkeeping’: a crucial discipline. He claims that when our industry doesn’t professionalize quickly, we have the risk that B&TDD will be enforced by law (too).
So, it can be wise to learn to practice it quickly.

It is not easy to start when writing (long-lasting) embedded systems. We have other demands, codebases with a lot of history. Still, we can (& should).
And we have an advantage, our Typically engineers are clever: When they understand the objectives, they will find a solution; that is their job!

Updated on 2020/07/15

This old article was never really published. As it fits my new MESS blogs, I reworked and posted it again. This is part-I; I expect other parts coming weeks.

Read more ...


The Never-ending Struggle on CodeQuality due to the growth of teams and codebases

reading-time:

6m

As your embedded software codebase grows, the risk of introducing errors and bugs increases exponentially. Doubling the number of developers will roughly double the risk of mistakes. We need new “tricks” to strive for the ever-demanded high quality.
This is a constant battle. As embracing tools, processes, or disciplines helps only once.

Read more ...


Why Modern Embedded Software Systems nowadays embrace webserver-technology

reading-time:

3m45

Whether it’s your office printer, your internet router at home, or your future top-notch embedded system, they all use technologies that, only a decade ago, nobody imagined using in an embedded system! How did this happen?
And why?

Read more ...


Pub/Sub

practice-time:

2 * 1 hour

The publish-subscribe architecture-pattern is very popular to route messages, according to WikiPedia. It is used much more generic, however. This workshop shows how to use it in an embedded application, or another single process application.
Then it becomes a HighTech (embedded) software design pattern.

We start with a simple implementation of Pub/Sub. You can experiment with that (Python) code and/or port it to your favorite language. Then, you are asked to design a cached, distributed version. Which is a bit more ambitious. And even though the result is probably pointless, it’s a great Design-Exercise and a lot of fun!

It will help you to understand Pub/Sub, help you to use it in embedded software. Eventually, you may need Pub/Sub in a distributed environment. Then, it is better to use one of the existing ones, like DDS (Data Distribution Service); which more efficient and even RealTime!
But, by knowing how to implement it and are able to design it, will help you to use it for the better

Read more ...


ThreadPoolExecutor

practice-time:

2 * 1 hour

This workshop is about the ThreadPoolExecutor (‘TPE’ for friends): a pool of workers implemented with Threads. This is a modern, advanced design-pattern available in many languages.

You will get an introduction to the concepts, to be able to use the ‘TPE’. Also, we study Python implementation, to practice design-analyse.

Read more ...


Requirements Traceability

study-time:

1 hour

Requirement-Management, and especially “Tracking Requirements” isn’t that complicated, but it needs some discipline. Often that discipline is replaced by a tool, which is encouraged by tool-vendors. That hardly ever works.

This blog introduces requirements traceability in a conceptual, but pragmatic way. It shows –as a demo– what a team has to do (defining requirements and describing the relations) and what the benefit is. It assumes a (more or less) agile way-of-work and shows how it can become lean. A small investment in good requirements definitions makes validations a lot easier.

And yes, it used a tool: a free one; as part of the documentation-system that is used for this side. An structured, version-controllable, textual way to write documentation, including all requirements. With a plugin that can visualize all specifications and their relations.
Those “particulars” will be shown too.

Read more ...


De Embedded Linux Expert bestaat niet

reading-time:

4 minuten

Regelmatig krijg ik ‘Embedded Linux Experts’ aangeboden; bijvoorbeeld voor het HTLD-team (HighTech Linux Delivery). Vaak zijn goede mensen, met Linux ervaring; maar toch niet de mensen die ik zoek. Het blijkt erg lastig voor niet direct betrokken, om de juiste experts te spotten. Daarom een paar hints waarmee je “de” Embedded Linux Expert herkent. Immers, alleen het woordje ‘Linux’ op een CV is onvoldoende!

Read more ...


dPID: A Python ‘homework’ exercise

practice-time:

1 hour

This is an optional exercise for the python-3 workshops: program a discrete PID-controller.

A basic class definition is given; which has to be tested and implemented. By starting with the test-part, which is advisable anyhow (the TDD approach), the exercise starts simple.

Read more ...