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 Summary. My Daily Note is one page, driven by the calendar, giving me a unified view. Every day it shows only what is
relevant to that period: today, this week, this month, this quarter, nothing more, nothing less. 

 I run three monitors, and I am picky about what gets a spot on any of them. The top one is reserved for a single
tab: my Daily Note.

 AI won’t deliver the productivity gains everyone expects, because models still aren’t good enough at complex tasks.
They need constant nudging, small pushes only a human can give. No prompt, no markdown file, no agent loop can
reliably deliver value for a business on its own. It works on side projects. Prototyping gets faster. Every now and
then, a couple of…
Never trust your model with write permissions. You’ve probably read the stories: models dropping production databases,
deleting emails, triggering outages. It happens when you hand too many permissions to your agent, especially write ones.
It’s tempting. It works, until it doesn’t.
Most mornings, I start with one blank note and dump everything that’s on my mind. In a few minutes, I feel calmer and
clearer about what to do next. 
 In 1920, Bluma Zeigarnik ran a study and found that interrupted tasks are remembered better than completed ones.
Surprisingly, they occupy human memory even after they’re no longer active. We know this as the…
Weekly planning doesn’t need a 2-hour retreat or a Notion template with 47 linked databases.
Here’s what 15 minutes of it looks like in practice. 
 
 
 
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Backtested: 16 years, $320k invested. The Magic Formula still has an edge. 
 
 
 
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 Disclaimer 

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Stateful Kafka Streams Processors: Reducing Rebalancing - Lessons Learned 
 Stateful Kafka Streams on Kubernetes need configuration to stay stable during rolling updates without causing lag. If your processor must be fast, runs on few partitions, and short lag matters, the defaults are not enough. Enable static membership with a timeout based on the worst-case duration of your rolling updates.
AI is making one part of engineering cheaper: producing text and code. 
 The misuse is assuming that cheap output produces progress. 
 Often it produces the opposite: teams generate more artefacts, spend more time validating them, and still do not make better decisions. Noise rises. Coherence falls. The bottleneck shifts from writing to judgment.
For the past few years, a familiar narrative has been circulating through the technology industry: artificial
intelligence will soon replace software developers. Each new model release fuels another round of predictions that
coding will become obsolete.
Read this if you want to: 
 
 see beginner examples that link Haskell’s syntax to its underlying mental models – types, pattern matching, declarative style and do 
 see examples of Haskell’s distinctive syntax in practice 
 learn what Robin Milner’s work changed in functional programming 
 write and run code as you go 
 

 Introduction 
 In the current AI era,…
This analysis applies to England, Wales and Northern Ireland. Scotland, which operates a separate income tax system, is not covered. 
 Income tax is one of the UK government’s largest sources of revenue, paid by roughly 32 million taxpayers. While the system is progressive by design, it contains features that materially alter tax rates over relatively narrow income ranges.
1. 3Monads 
 
 This is my personal project to replace the task manager I currently use. My goal is to build a tool with better calendar integration,
improved note-taking support, and Vim-like navigation. I also want to support tasks belonging
to multiple projects and eliminate the trend of unnecessary AI integrations — focusing instead on a clean,
minimalistic, Vim-inspired…
The best way to approach concurrency is to master the fundamentals.
Below is a small collection of foundational concurrency problems with practical solutions using Scala and Cats Effect. 

 Conclusion 
 In this post, we explore four fundamental concurrency problems and their idiomatic solutions using Scala and Cats Effect,
but which could be generalized to any programming…
Problem 
 I’ve always had mixed feelings about scalacOptions += "-Xfatal-warnings" . On one hand, it’s an inevitable PR review and code quality boost—I no longer have to comment on unused variables or imports. On the other hand, it kills experimentation and creativity. I’ve spent countless hours fixing unused variables and imports just to test something quickly.
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Ten years ago, I made a pivotal decision that changed my career trajectory—I incorporated my own company, Codeily LTD. This move allowed me to transition from a permanent role, where I often felt unfulfilled and bored after about a year, to becoming a contractor. Despite the bad press and disdain from my permanent colleagues, it was one of the best decisions I’ve ever made. Alongside choosing…
Data analysis doesn’t always have to be intimidating. By leveraging powerful Python libraries and Google Colab’s user-friendly platform,
you can dive into data analysis without any installations or setups. This guide is tailored for beginners and will
walk you through a practical application: analyzing survey comments.
In this post, we learn the basics of data manipulation in Python. We’ll use the following: 
 
 Regular Expressions 
 Numpy 
 Pandas 
 

 Regular Expression 
 Let’s start from this string and basic imports:
In Data Science, understanding some math is essential. Let’s review some essential math methods in Python grouped in: 
 
 Basics 
 Linear Algebra 
 Probability 
 Statistics 
 

 Basics 
 Basic operations on sets 
 set(range(1, 10)) // a set
 mod2 = {x for x in range(1, 10) if x % 2 == 0} // another set
 mod3 = {x for x in range(1, 10) if x % 3…
There is a lot of noise around AI. Even though it was an ambiguous topic in the past, it has become unbearable nowadays. People throw AI in their startup names, and companies rebrand their products…
Definitely Yes. 
 Whenever you read a book or learn a new skill, it changes you. It lets you look at the world and life differently. Similarly, a degree, any degree. Even if you don’t see tangible benefits immediately.
1. The goal of this article 
 Investing may be fun. However, starting is always challenging. This article may suggest some questions you should ask yourself before your investing journey. 
 It is not enough to start investing with some facts without a deep understanding of them. More importantly, we should know that all of them have some drawbacks. We all know that putting eggs in one…
1. Rules of the game 
 Finding a developer’s job used to be complicated. With the ever-growing demand for IT specialists, companies struggle to hire ideal candidates quickly enough. They must pick from juniors or non-technical people willing to learn. Therefore, the ability to train new joiners has become a competitive advantage nowadays.
Make sure you meet with everybody before you join the very first meeting. You need to understand how your team members’ names are pronounced. 
 Moreover, have a plan (5 steps ahead - which describe your first ten weeks - one step per two weeks, your goals). I suggest creating this just after day one before you start meeting with people. Remember, this plan will go to the bin later, but…
1. Abstract 
 I will use this blog as an opportunity to frequent rethinking my direction. This is the very first post to describe my activity. I’m jumping on the show-your-work bandwagon and sharing my work-in-progress and random thoughts with you.
1. Abstract 
 I was debugging a microservice. It was my first time with this code. I realized that everything works till Redis, which is probably not updated. That’s why end users don’t see what they should. The hypothesis was sound and worth testing, but how to do it?
1. How to write good code 
 One may think functional programming is an abstract concept, not very useful in projects, “I use Java, and it works”.
However, this is just like saying, why bother with Software craftmanship. Everything could work even if we boil down our code to one
class with thousands of lines. We all know how projects like that end.
1. Problem 
 Sometimes as a developer, you need to implement a system for a power plant, a banking system, or anything that is not a hello-world project but has many moving parts (like integration points, different internal projects created by various teams).
1. Abstract 
 I created a personal productivity system, which you can also use. It allows implementing all my ideas.
Additionally, it can be considered an organisational system as it aggregates all things that matter and need to be moved forward.
It may be inspiring for anyone who wants to improve their own. It can also be a game-changer for anyone
who thinks everything can happen…
The system 
 I was happy. Finally, after six years of terrible user experience, I was going to close my bank account. The prerequisite for doing this was to repay the mortgage, which I had already done the previous week. Why during COVID was I still going to risk my health and visit the bank branch? Why not close my account online? It’s because they don’t provide this feature. Why?…
I was a dissenter 
 During my MBA program, I had a great experience during my Fostering Creativity class. In my previous post I described how creativity can be learned and used in a business setting. Here I’d like to present how dissenting can impact the group dynamic and how it influences the final outcome.
I don’t remember having any lesson in creative thinking at school. Yet, creative thinking is fundamental to individuals and organizations. When I first heard about this, there were immediate negative connotations involving business coaches and ineffective company brainstorming meetings. I used to think creativity was exceptional, almost like the initiation of some kind of magic moment, as…

 Let’s say you passed a job interview and was handed a salary offer of $90,000. Would you be happy to accept it? 
 
 Or consider the interviewer’s perspective: 
 
 How much salary should you earn to be in the top 95%?
Companies tend to hire people with or without a modicum of experience and call them juniors. That’s fine. However, I’ve come across managers who would hire as juniors mid-level candidates who failed the interview.