I'm Karol Działowski

Also known as karlosos, full-stack with AI/ML background.
I like to build things that solve (my) problems.
Big fan of React, tRPC, Python and Golang.

GitHub Get in Touch

My skills

Web Development

Computer Vision

Knowledge Sharing

My projects

Kindle Clippings Manager

2021

Kindle Clippings Manager written in React and Redux.

Import, browse and delete kindle quotes. Use offline as a PWA.

getbibtex.com

2021

Simple application to generate BibTeX entry from a given url.

Created using React/NextJS with tRPC as a backend. Implemented admin dashboard with analytics.

Time Task Tracker

2022

Offline first (and offline only) PWA for tracking Jira/Linear burned time.

Persists data in Redux/localStorage. Implemented exporting/importing functionality.

PitchMap

Private

2019

Tracking football players on the playfield captured by a moving camera.

Deep learning, Computer Vision, OpenCV and other buzzwords! 🤓

Smarthome WebApp

2020

Smarthome web application written in React and Fastify.

Created during Intive Patronage.

Catan Dice Roller

2022

PWA for rolling dice with Catan art.

The app has sounds 🔊 and cool animations 💫.

Todoist Clone

2020

Todoist clone written in React and using React Context based on tutorial.

Backend created with Django Rest Framework from scratch without tutorial.

See more projects on GitHub

Most of my public projects since 2013 can be found on my GitHub @karlosos

Recent blog posts

Synchronizing timers in React

Sometimes we need to have two synchronized clocks in our app. In this blog post I show implementation and usage of useSynchronizedInterval hook.

#react

2024-02-12・3 minutes

Please use TypeScript enums

TypeScript enums are not harmful or terrible. String value enums are completely fine. I am questioning if POJOs are the silver bullet (they are not) and I am debunking your favourite TikTok (YouTube) influencers!

#typescript

2023-12-04・4 minutes

Implementing hold to confirm button in React

This blog post delves into the creation of a "hold to confirm" button using vanilla React, addressing its potential advantages and drawbacks. It highlights concerns related to user familiarity, accessibility challenges, and suggests considering alternative UX patterns.

#react #ui #ux

2023-06-25・3 minutes

My 14 Days Long Story About Upgrading React

My review of React upgrade journey in my project. Explored problems with React.FC, userEvent, Redux types and massive number of almost one thousand failing tests to fix.

#react

2023-02-25・3 minutes

Code reviews taking too long? Here are 7 ideas for preventing PRs from getting stuck

In this blog post, I'll explore 7 ways to prevent code reviews from getting stuck and speed up the process, including limiting work in progress, making pull requests easy to review, and effective communication with reviewers.

#code-review

2022-12-08・5 minutes

Running old Ruby on Rails application with Docker

Post explaining how I've managed to run old (5+ years old) web application with Docker without much hassle.

#docker #ruby-on-rails

2022-08-04・4 minutes

Automatically Restarting Heroku App With Cronjob

In this blog post, I describe the solution for automatically restarting the Heroku application. Restarting is done with the use of Heroku API and the dedicated NodeJS script. However, this problem can be also solved without writing any line of code.

#heroku #cloud

2021-10-20・1 minute

Football Data Visualizations - Passing Networks

During Euro 2020 I've seen a lot of good-looking visualizations on Twitter (see those created by Maram AlBaharna and Matteo Pilotto. There's also plenty of other data scientist, some professional and some amateur, who create soccer data visualizations.

#python #data-science #football

2021-09-14・7 minutes

Disabling captions in LaTeX subfigures and dividing figures between multiple pages

While writing my thesis paper I have encountered problem with subfigure captions. I wanted to get rid off subfigure numbers, i.e. "(a)" or "(b)". I didn't want to disable subcaptions in entire document but do this locally.

#latex

2021-05-01・2 minutes