Data Scientist | | makes data make sense

What are the most important turning points in a data scientist’s journey?

Don’t let the trees prevent you from seeing the forest. Poland 2021. Photo by the author.

It is not easy to tell when does exactly a data science cadet becomes an actual data scientist. Unlike in the army, we do not have distinct ranks that would correlate with seniority. Neither is a career path of a data scientist linear. …

On the benefits of building trust, precision, and awareness of one’s skills

Moon rise on night summer sky in Northern Poland — a break from dealing with…

I want to expand this work into a series of µ-tutorial videos. If you’re interested, please subscribe to my newsletter to stay in touch.

The tech world surrounds us. It penetrates nearly every aspect of our lives not only through devices and services that we use, but it also affects…

Data, stones, and data and more stones…
Atlantic coastline, stones, data, more stones. Portugal 2019. (photo by the author)

I want to expand this work into a series of µ-tutorial videos. If you’re interested, please subscribe to my newsletter to stay in touch.


Data analysis is one of the most essential steps in any data-related project. Regardless of the context (e.g. business, machine-learning, physics, etc.), there are many ways…

Simple usage of a reverse SSH tunnel for to greatly improve the usability.

This was not an SSH tunnel, but still a reverse one. Sintra, Portugal 2019. (Photo by the author).


It’s been quite some time since we wrote on any “engineering-like” topic. As we all want to stay efficient and productive, it is a good time to revisit Google Colaboratory.

Google Colaboratory, or Colab for short, has been a great platform for data scientists or machine-learning enthusiasts in general. It…

Python Pandas and SQL — time aggregations and syntax explained.

Waiting for a good moment, Poland 2021. Photo by the author.


Working with time-series data is often a challenge on its own. It is a special kind of data, where data points depend on each other across time. When analyzing it, your productivity at gaining insights to a large extent depends on your ability to juggle with the time dimension.


A few tricks on how to learn quickly — especially in the Data Science world.

“Looking up”, Poland 2021. Photo by the author.

Technology is fascinating. It is the missing link that brings tomorrow’s dreams today. It is also an attractive career for many — engineers, managers, entrepreneurs, and all kinds of problem solvers are welcome.

Unfortunately, there is also a catch. The catch is the ever-changing technology landscape in combination with an…

Not every cloud is about data, but navigating may be equally hard. (Photo by the…

Data analysis is by far one of the most frequently occurring tasks in both business and technology. It is the daily bread of thousands of academic researchers, bankers, engineers, and, obviously, data scientists. Interestingly, despite being such a popular activity, there seems to be no agreement on what should be…

A good day.
How a good day looks. Photo by the author.

Rarely do I get a feeling that there is not enough advice to go around. It’s quite the opposite. Advice is often free and accessible, despite not always being useful or applicable.

In this article, I would like to share some thoughts on what I think is useful. It is…

Oleg Żero

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