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Codility Team

We are dedicated to helping companies hire better programmers and improving programming skills worldwide.
With our automated assessment tests and professional assessment services, we help recruiters around the world save hours of precious time in recruiting software developers. Our programming tests let your candidates demonstrate their abilities in a natural working environment, showing you how they will really perform on the job.
The idea for Codility came about when our founder, Greg, was looking for a quick way to recruit the 20 additional software engineers needed by the IT start-up he worked for in China, while at the same time saving money, time and avoiding stress. The result was the beta version of Codility: a tool to filter out the 90+% of candidates who are unable to deliver correct solutions to easy programming tasks. (Read the full ‘genesis’). In 2009 the Codility team entered the Seedcamp Competition, won it, then registered in London, UK and continued to grow, drawing only from that original investment. Over the next few years, Codility developed very quickly and moved to Warsaw, Poland where most of the team is now based. Since then, more than 1100 companies in over 120 countries have used Codility and over 700,000 tests have been assessed.

Grzegorz Jakacki CEO and Founder

Greg has been programming since the 1980s, working with various teams in the US, China and Poland. In 2005, working as a senior software engineer in Beijing, China, Greg co-organized a massive hiring campaign and came up with an idea about how to automate the recruitment process. The idea eventually evolved into Codility. Greg holds an MSc in Computer Science from the University of Warsaw. In the past, Greg has won a bronze medal at the International Olympiad in Informatics, co-organized numerous programming contests, co-designed a specification language called SystemVerilog Assertions, led the development of an open-source C++ front-end compiler (OpenC++) and translated several technical books into Polish, including Donald Knuth’s “The Art of Computer Programming”. Outside of Codility, Greg teaches classes in advanced programming at Warsaw University, hacks at Warsaw Hackerspace and is a passionate pianist and organist.


Marcin Kubica Chief Science Officer

Marcin holds a PhD in Computer Science and draws from 20+ years of experience as one of the organizers of the Polish Olympiad in Informatics (POI). He was one of the developers of the first automated evaluation system used by the POI. As well as the POI, he has taken part in the organization of many other programming contests, including the International Olympiad in Informatics (IOI), where for six years he was on the Scientific Committee. Marcin combines his work for Codility with researching and lecturing in computer science at the University of Warsaw. Next to being our silverback, with an unmistakable sense of humor and eyes set on quality, he is a skywatcher, a believer in the magic of 42 and the proud father of three children.


Tomasz Waleń Founder and Senior Software Engineer

Tomasz is a software practitioner and theoretician. He has designed and implemented evaluation software used in major programming contests worldwide. Tomasz is also involved in teaching advanced subjects in computer science, as well as in research on text processing algorithms. Tomasz holds a PhD in Computer Science from the Faculty of Mathematics, Informatics and Mechanics at the University of Warsaw.

Zuzana Bednarikova Head of Customer Support

Zuzana graduated from the University of Limerick, Ireland in Applied Languages and holds a Master’s degree in Business Management from the same university. Originally from the Czech Republic, she enjoys living abroad and is a polyglot. In her free time she loves skiing, singing and socializing.

Wojciech Ptak Software Engineer

Wojciech is studying Computer Science at the University of Warsaw with a focus on machine learning. He is a hungry, pragmatic and fearless coder, a passionate bass player and a sailor.

Tomasz WesołowskiSoftware Engineer

Tomasz studied in Poland and Sweden and holds an MSc in Computer Science with a specialization in artificial intelligence from Warsaw University of Technology. He has an insatiable hunger for knowledge, loves to try out new tech and is at home in both front-end and back-end coding. He is a prolific technical writer with a knack for tutoring. A true specialist at work, he treasures discoveries in his private life, most notably tea, piano, chiptunes, books, books and books.

Paweł MarczewskiTech Lead 

Paweł graduated from the University of Warsaw with an MSc in Computer Science and BSc in Mathematics. His interests are manifold, from natural language processing to artificial intelligence and logic programming, and his curiosity and hunger are hard to match. Paweł has been a voluntary tutor at many summer schools for gifted high school students. He is teaching himself Japanese, becomes competitive in Asian board games and likes science fiction literature.

Natalia Panowicz Chief Operations Officer

Natalia majored in Psychology (MA studies in Poland and Belgium) and earned a business degree (magna cum laude) from Vlerick Business School. Prior to joining Codility, she consulted in Guatemala, did research and managed an NGO project. She is motivated by impact, people and insights. Outside of Codility, Natalia hacks food and has a strong passion for perfumes.

Michał Kowalczyk Software Engineer

Michał is a bronze medalist of the Polish Olympiad in Informatics, a participant in multiple programming and hacking competitions (e.g. Capture The Flag contests) and co-organizer of Wakacyjne Warsztaty Wielodyscyplinarne—a summer camp for gifted high school students. Michał started working at Codility as an intern, with a focus on security and execution sandboxing. Currently our ‘little (ethical) hacker’, with coding apparently part of his DNA, works for Codility as much as his studies allow him to.

Mateusz Klimek Software Engineer

Mateusz studies Computer Science at Warsaw University, currently writing his master thesis about one of Codility's projects. He joined Codility in June 2011, right after his exams. He enjoys algorithmic puzzles, has infected many other people with his passion for juggling and plans to do the same with dancing.

Marcin Kaszyński Senior Software Engineer

Marcin is a software developer, teacher and entrepreneur. He holds an MSc from the University of Warsaw, specializing in distributed and parallel programming. Coding for a living since 1998, he co-authored or led the development of multiple systems including data acquisition and visualization software, an online energy trading system, report generators, language translators and interpreters, and a numerous different web applications. He plays an active role in the Polish start-up community by organizing developer meet-ups and workshops. He’s also one of the founders of Warsaw Hackerspace, which was the first such community in Poland. Marcin worked on one of the early versions of Codility, left to become a CTO of another start-up, helped it develop a novel TV/movie metadata normalization system until it got acquired, and returned to Codility.

Magda Tworek Office Manager

Magda graduated from the University of Economics in Katowice and then worked in Learning & Development, HR and Clinical Services in both Poland and England. Her passion for the world and travel took her on a solo world tour. During another of her many travels she and some friends climbed previously unexplored peaks in the remote Bolivian Apolobamba mountain range, and had the privilege of naming one of them Akuku.

Maciej Pasternacki System Admin

Maciej has an MSc in Computer Science from the University of Gdańsk. Having worked initially as a sys-admin, then as a developer, then as a freelance web developer, he finally found his niche in web operations and infrastructure development. Now he helps web projects to keep the lights on, and tries to script himself out of his own as much as possible. In his free time he enjoys rock climbing and hiking. He’s a bit of a railroad nerd as well.

Krzysztof Gogolewski Software Engineer

Krzysztof graduated from the University of Warsaw with a MSc in Computer Science and a BSc in Mathematics. He loves computational complexity, functional programming in Haskell, theoretical computer science, Gustav Mahler, foreign languages and dark humor.

Joanna Marciniak Office Assistant

Joanna draws from a wealth of experience in Poland and abroad, from managing golf courts to logistical coordination at NSN. At Codility she designed and oversaw the implementation of our brilliant office/home and is a multitalented treasure. She may be conservative in her approach to new technologies but she cannot live without cool gadgets. She’s a bookworm who used to sail and ski a lot before she became a (passionate) mum… but she still believes that’s not the end of the story!

Jacek TomasiewiczSoftware Development Consultant

Jacek is an MSc student in Computer Science at the University of Warsaw. As a brilliant programmer with a passion for sharing his knowledge and helping people excel at coding, he is the author of many of Codility’s tasks and challenges, and he also builds our free guided programming class. He is a jury member and author of tasks at the Polish Olympiad in Informatics (POI) and frequently lectures at IT summer camps. He calls your bluff at poker and doesn’t mind a drink with friends from time to time.

Dorota Koszewska Financial Director

Dorota graduated from Warsaw University of Technology with a MSC in Engineering. She went on to postgraduate studies of accounting and corporate finance at Warsaw School of Economics and holds an MBA from the same institution. Dorota has been a member of management and supervisory boards of several companies. Her professional focus has gradually switched from property management to corporate accounting and finance. In her leisure time she is passionate for motor sports, especially car and motorbike racing. She is a motorcyclist herself, loves to travel and get acquainted with different cultures.

Dominic Lüdin Product Manager

Dominic was the first user of ‘Codility’ back in 2005 in China, where Codility has its roots, and where he worked for four years. Having experienced the value of Codility first hand, he recently joined the team motivated to help increase its worldwide impact. Dominic has worked for start-ups in the IT and Renewable Energy sectors in China and Switzerland ever since he graduated with an MA in International Relations from the Graduate Institute in Geneva. He is intrigued by the design of human-friendly, ‘obvious’ technology. He learns languages to access people’s stories and is a keen photographer.