I have over 15 years of experience in software engineering and graphic design. I like climbing, drawing, playing piano, board games, graphic novels, and books. Read more about me at bartkozal.com.

Connect with me on LinkedIn, Instagram, 𝕏, and GitHub.

I started in C++ then professionally focused on Ruby, Swift, and JavaScript. Through all the years I worked on games, web applications, native, and mobile apps. I have experience working for startups, scaleups, and large companies in technologies like: JavaScript, TypeScript, Node.js, React, React Native, Electron, Next.js, Vue.js, AngularJS, Ember.js, GraphQL, Swift, Objective-C, Ruby, Ruby on Rails, PostgreSQL, MongoDB, MySQL, Elasticsearch, Redis, RealmDB, Docker.

I developed over 30 open source libraries in various technologies and contributed to projects like Rails and ycmd. My most popular repositories are:

1. Float label pattern (vue-float-label)
2. Universal and lightweight stylesheet starter kit (hocus-pocus)
3. Text-editor-like weekly planner (coypu)
4. Flexbox based responsive fraction grid system (vue-fraction-grid)

Between 2012 and 2016 I was a core team member and then the CEO of a startup. Shelly Cloud was an automated hosting platform that made deploying Ruby applications painless. We hosted over 270 paying applications on 430 virtual servers. I worked in all areas required to build and run a successful product: user experience, front-end and back-end development, server administration, support, marketing, sales, and team management.

I was a solopreneur for over a year and created a few indie products. One of them was promoted by Apple in the AppStore and reached over 130.000 users. Now they are all open-sourced. You can find them here:

	Project	Description
	Mood Tracker - Track daily mood with emojis	iOS/Android app for improving mental health built in React Native, Expo and TypeScript.
	Echotags - Hands-free, Amsterdam audio guide	iOS app built in Swift using UIKit, Core Location, Core Audio, RealmDB and Mapbox API, along with Rails web app to manage content.
	Coypu - Text-editor-like weekly planner	Cross-platform todo app. Built in Vue.js, Electron and PouchDB.
	Games Tracker - Track your games collection	Single page app built in React and powered by API built in Rails designed to track owned and played games.
	Checkers for iMessage - Board game for iOS10 iMessage	iOS app built in Swift using SpriteKit. One of the first iMessage apps on the market promoted by Apple with over 130.000 users.
	Jottings - Real-time collaboration in Markdown	Built in Rails, Vue.js, Express and ShareDB. Extensively used Operational Transformations and contenteditable API.
	Game Night - Schedule board game nights	Simple Next.js and Supabase project.
	Ukulele Tabs - Translate music notes to ukulele tabs	A small tool created in React to translate notes to ukulele tabs.
	Major Scales - Practice major scales	Small tool built in React to practice major scales.

I enjoy spending my free time pencil drawing. I know how to use all popular graphic software including 3D software like Blender. I self-studied character design and animation. I was also working on procedurally generated graphic and physics simulations. I participate in drawing challenges like Inktober.

I like playing piano. In 2021 I started attending jazz piano lessons and studying music theory. I know how to use DAW software. I designed sound for my animations.

My other hobbies besides coding, drawing, and playing jazz are: climbing, board games, graphic novels, and books.