During one technical coding interview, I prefaced my answer with this:

“I assume the answer is what I would do in real life, working in a team who need to quickly understand and debug my code. And the code would scale and be testable.”

My answer is not a “toy” answer. I code for real life.

Instead of an “elegant” approach which calculates results in a single pass, my solution achieves its result in several stages, holding intermediate results in a calculation matrix with the same number of rows as the data matrix.

I prefer a segregated, staged approach so…


Although many workers were successful at converting to remote work, I fear one aftermath of the COVID-forced remote transformation is that employers will realize they can shift jobs to cheaper labor [2] where cost of living is lower (namely inland South America, SouthEast Asia, Africa, etc.).

I predict that internet from space will enable a flow of paychecks out of developed populations to less developed locations around the world.

At 60 satellites in each of 20 Falcon 9 rocket launches in 2020 and 400 in 2021, Elon Musk’s privately owned SpaceX [1] is putting up to a constellation of 42,000…


From movie “Ford vs. Ferrari”

We see in movies that in the 1900s managers oversaw their production line by standing on a platform high above the factory floor, where people can be seen and counted.

That approach can’t work today for businesses running within computer systems with workers working from home. Instead, SREs install tools to shift the practice of management from manual approvals to automated scanners:

  • Code “linters” that flag when coding is not formatted or named according to standards
  • “Static code scanners” that ensure secrets are not hard-coded in code but retrieved only when needed from a vault of secrets
  • “Contract tests” that…

Photo by saeed karimi on Unsplash

Use my shell script to save secrets in a virtual vault in Amazon’s KMS (Key Management Service) which can automatically supply your programs the secrets it needs based on AWS IAM roles.

STATUS: I’m still working on this one July 24, 2021.

Programmers who use code intended for “learning” in production systems inadvertently introduce vulnerabilities and exposing the organization to data leaks and ransomware.

Many tutorials on coding Bash shell scripts offer sample code containing passwords, API keys, or other secrets as clear-text embedded with the request to a database or web service API. An example [1]:

curl -d '{"auth":{"passwordCredentials":{"username"…


Being really effective at working remote doesn’t happen just because you’re sitting at Starbucks. Here’s a deep dive into the many little tricks I’ve learned doing it (from Montana) before it was cool.

Photo from https://runningremote.com/remote-working-skills

I tell recruiters I prefer remote WFH (Work from Home) not just because I don’t want to waste time commuting (I’ve gotten in accidents driving home tired).

It’s because I’ve found that managers and companies who strive for effectiveness with a remote crew are better employers. Here’s why:

Companies that use remote workers as a strategy will have a better chance of survival in…


In sports, announcing the score to a game would be incomplete without specifying the score from both teams, right?

Here is a short checklist of best practices for showing statistics so that your viewers focus on reality and actions.

Instead of single numbers, show a line of the numbers over time so that viewers get a sense of the history of that metric.

But do you know of someone who look at a line and comments with the assumption that “going up is good”, “going down is bad”?

Not necessarily, so provide a clue about what constitutes desired levels in…


TL;DR

I wrote Bash scripts to automatically type out Qwiklab’s manual instructions on Google and Amazon clouds. In the process, I got good and quick at various scripting tricks, and am less frustrated with typos.

Now I’m building a community of people (you) so we can do more labs and learn from each other so that you too can transfer achievements in Qwiklabs to your own workplace.

Try It

I wrote the script so that I can run the whole tutorial by copying and pasting this one command:

sh -c "$(curl -fsSL https://raw.githubusercontent.com/wilsonmar/DevSecOps/master/qwiklabs/gcp-cloudml-GSP076.sh)"

But I hope that you’re the skeptical type and…


It was like a dream in a movie with an eerie soundtrack. Dozens of people around me on a bus. None of them know my anguish of losing all the stuff that I had accumulated in my backpack. Laptops. Headphones. Batteries. I wanted to scream and cry at the same time.

Here is what I’ve learned from getting my life back together again.

As soon as I realized that I no longer knew where my backpack was, I’m thinking: Nah, it must be around here somewhere. …


“My customer wants me to guarantee user response time at internet scale” lamented a colleague who was hired as a performance tester, someone who measures the speed and capacity of websites by creating stress on them by writing programs that pretend to be a large number of users.

“Our manager likes the old TV commercial where that guy says ‘I guarantee it’. He wants to be that guy.”

“But providing a guarantee is not the traditional role of a performance tester” he noted. “I only impose an artificial load and measure, and leave it to others to figure out why”.

QA scare built to be separate

Wilson Mar

Leader in DevSecOps in CI/CD performance in machine learning and data systems

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