Louis Petrik
Obviously me. Source: Also me.

Hi, my name is Louis. I’m 20 years old.

In this post, you can find out what I do away from espresso commercials.
Here is a small overview:

About me Where to find meContent on various topics you might like: 
- Programming
- Money / Finance
- Philosophy / Society
- Self / Life
- Writing
- Marketing

What happened since my birth — About me

It all started 19 years ago, with my birth in Hildesheim, Germany. (Trust me, Hildesheim is one of the most beautiful cities here in Germany).

In 2020, I finally graduated from high school. …

Source: @hostreviews at unsplash

Protect Your Money — From a Bankruptcy

In most countries of the world, there is so-called deposit insurance.

This insurance usually is government-sponsored and guarantees that the amount you had in your account at a bank that, for example, went bankrupt, will be fully refunded up to the amount of the deposit insurance.

So if the deposit insurance is $100,000 and you had $80,000 in your account, you get the full $80,000 back. If you had more than $100,000, then you lost everything over $100,000.

The trick is to divide the money into several accounts since the deposit protection always applies per account. So if you are…


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1. Digital money makes us decadent

You can buy anything almost anywhere.
Thanks to modern technology, we don’t even need our wallets anymore.

We can pay on the internet with PayPal, in stores with Apple Pay, Google Pay, or simply with our credit card. We don’t really need cash anymore — paying digitally is usually much more comfortable.

But without us realizing it, it costs us more. The convenience of digital payments is that we don’t have to touch our money — which is the downside. We lose the sense of money and how much we have.

Anyone who has ever paid with cash knows the…

Blockchain / Programming

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Blockchain technology is a fascination. Especially for developers, it challenges what you know and understands about tech. Therefore, blockchain tech hooked me very early. Like with all tech stacks, there is something we can learn from it. So, which programming languages do the blockchains use? And what justifies their choice? Let’s see how the brave new world is built!

Cardano — Haskell

I love the Cardano blockchain. The more I wanted to find out what it is driven by. When doing so, I was surprised: Haskell is the programming language driving Cardano. Nearly everything, the wallet, the nodes, and the smart contract language…

Source: purescript.org

Lately, I got interested in functional programming. People say that learning it will make you a better programmer.

Therefore, I wanted to try a purely functional language: Haskell.
Yet, I didn’t have a use case for it. In the end, I want to bring stuff into the web—even functional programming. So I researched and found a highly promising project: PureScript.

The project amazed me so much that I want to show it to you. If you are as excited as me, let’s dive into PureScript and purely functional programming for the web.

So, what is PureScript?

At first look, PureScript looks like Haskell. Just…

programming confusing words
Photo by Oladimeji Ajegbile from Pexels

1. Concurrency

This is one of the most misused concepts in computer science. When thinking about concurrency, we often think two things are running at the same time — parallel to each other. This isn’t necessarily the case with concurrency.
Parallel running is called parallelism — which is not the same as concurrency.

There is a good quote by Rob Pike to sum up the difference:

“Concurrency is about dealing with lots of things at once. Parallelism is about doing lots of things at once.”

To understand concurrency better, it’s valuable to know that even a single-core system can run in concurrency…


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What's the first thing you associate with programming?

If you never wrote code before, it might be maths. On the other hand, most programmers I know don’t associate what they do with maths. At least not much.

Instead, they associate it with logic. Yet, the idea that programming skills are linked to maths abilities sticks — even among programmers.

But what if your mathematical skills aren’t a strong predictor of how well you could learn to code? A study from the University of Washington just confirmed this. The study serves as the source for this article.

While maths wasn’t found…


Gemini Node.js
Source: the author

Gemini protocol? If you never heard of it, don’t worry — it's not known to many. The Gemini protocol builds on the dissatisfaction with the internet we know, driven by the HTTP protocol.

Yes, Gemini is, what I called it — a protocol. It's not a subset of the web — it runs on its own protocol and cannot be accessed with normal browsers.
But why?

Gemini doesn’t aim to replace the internet we know. Amongst the aimed differences to the web, Gemini has:

  • More privacy and security. The protocol mandates the use of TLS for encryption. There are no…


Development platforms like Firebase got more and more popular. Through providing serverless hosting, scalable databases, and other features like authentication, make developing apps easier. While Firebase has a huge position in the market, alternatives are on the rise. One of them: Supabase (no, I didn’t mistype).

The platform claims to be a Firebase alternative. And actually, I love it so far. While it doesn’t offer as many features as Firebase, it already offers some important ones: Storage, Authentification, and a Database (which I love the most).

We are going to build a small to-do list database example using Node.js. The…

IndexedDB in JavaScript

You surely know the local storage and cookies. Both allow us to save data permanently in the browser. Yet, both features are based on the key-value pair approach. Say we want to save a user's age, we would use the user's name or ID as the key — the value is the age itself.

This is useful but not optimal for storing more structured data. Structured data? The browser got our back. Yet, the so-called IndexedDB is not as popular as cookies and local storage. …

Louis Petrik

Programming, Finance & Psychology. Figuring out life, one idea at a time.

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