The interesting information first: I am working on a series of educational Kotlin videos!
My name is Jakob Löhnertz, I was born in raised in Germany, and I am living and working in the Netherlands nowadays as a software engineer at the Amsterdam-based online supermarket Picnic.
I am a Kotlin fan since many years and use it a lot for large-scale personal projects. I decided some time ago to start an educational YouTube channel since I have a long-running interest in becoming an educator and I am originally self-taught in our domain myself.
The YouTube channel is called The Self-Taught Software Engineer and covers everything from beginner programming courses to advanced material regarding specific engineering topics. My goal is to provide interesting and engaging, high-quality, educational videos to everyone interested in developing software – free of charge, accessible, and to the point! I specifically want to leverage my perspective from being self-taught myself to give a view onto the topics that something like university sometimes misses.
But enough of the boring introduction, let me share why I am making this post here:
Since Kotlin is my favorite programming language, from the start of planning the channel and its videos, it was clear to me that I will use Kotlin as the vehicle of explaining the subjects.
Furthermore, I was planning from the beginning to specifically focus on educational Kotlin content as well!
Therefore, I started a series titled Idiomatic Kotlin where I cover one topic that is specific to the language in each episode. The structure of the videos is based partially on explanations using slides and self-made graphics while a big focus lies on the real-world-esque code examples that I prepare with a lot of love for each episode to explain the topics on something that is more than just a two-line snippet that one would never encounter in the wild. I want to show the viewers how they would apply this in their day-to-day software development. All those examples I am also committing to a public repository on GitHub such that everyone can follow along, explore the examples, and even execute them locally to play around with them and truly understand the subject at hand.
Today, I released the second episode and I figured this warrants making this announcement here. I presume that many people in this community already know most of the things that I am sharing. However, I’d be very happy for feedback, future episode suggestions, and if you liked it, that you share it with people that would benefit from the content.
The first episodes were:
- Scope Functions
- Collections vs. Sequences
Enough of the talking, I’ll let the videos speak for themselves now. I hope you like them as I invest a lot of love into the preparation of the examples, graphics, and the presentation. Nevertheless, I am of course happy with any feedback 
Also make sure to check out my other content (I already have two videos on IntelliJ IDEA), if I caught your interest.
Here’s today’s episode Collections vs. Sequences (https://youtu.be/65VKQ-qdo3A) where I am explaining the differences between using collections and sequences within the Kotlin Collections API. I am covering what they are, when to use which, and what pitfalls are that one has to be aware of when using them.
And this is where you can find the aforementioned examples: https://github.com/The-Self-Taught-Software-Engineer/Examples/releases/tag/idiomatic-kotlin%2F%2302_collections-vs-sequences
Thank you so much for reading. Enjoy and get in touch with the channel and me!