Adam Stelmaszczyk, Algorithms Developer in Warsaw, Poland
Adam Stelmaszczyk

Algorithms Developer in Warsaw, Poland

Member since April 8, 2017
As a curiosity-driven constant learner, Adam is interested in mathematics, computer science and artificial intelligence. Having come across programming at a very young age, he grew up solving problems and especially enjoys when the solutions involve creativity. A good communicator and people person, Adam has a good eye for detail. He has worked in teams of all sizes and actively participates in open source and AI competitions.
Adam is now available for hire




Warsaw, Poland



Preferred Environment

PyCharm, Vim Text Editor, Git, Linux, GNU

The most amazing...

...thing I've done is taught a human model how to walk using deep reinforcement learning and 80 CPUs.


  • Machine Learning Engineer

    2018 - 2018
    • Optimized Facebook and Google ads.
    • Devised and implemented five ads optimization algorithms, with one showing a significant improvement.
    • Introduced and automatized split testing to compare the algorithms fairly.
    • Contributed to the jobs architecture, code repository structure, reviewed code, and helped others.
    • Designed, conducted, and analyzed experiments, prepared technical reports and a strategy for next steps.
    • Devised a way to find similar campaigns and to have even more data to leverage.
    • Conducted 1-hour AI learning session for 15 people.
    Technologies: Google Ads, Facebook Ads, Google Cloud, BigQuery, MongoDB, Git, Python, Monte Carlo, Testing, Mathematics
  • Machine Learning Specialist

    2017 - 2018
    GridCell (via Toptal)
    • Implemented custom reinforcement learning environments in Python compatible with OpenAI gym.
    • Tested various deep reinforcement learning algorithms such as DQN and PPO.
    • Deployed, trained, and hyperparameter tuned models on Google Cloud Machine Learning Engine.
    • Provided technical advice.
    • Documented every step and environment detail needed to reproduce the experiments.
    • Learned about Differentiable Neural Computers and implemented new training task in the DeepMind's code.
    Technologies: Python, Google Cloud, TensorFlow, Deep Reinforcement Learning
  • Software Engineer

    2015 - 2017
    Smarkets, Hanson Applied Sciences
    • Collaborated on research, design, and implementation of state-of-the-art market pricing algorithms.
    • Partnered in research, design, and implementation of anti-fraud micro-service for auto flagging suspicious activity, using Random Forests.
    • Increased the trading performance N times by parallelizing computations onto N shards.
    • Discovered, wrote tests, and fixed multiple severe bugs. Fixed more than a 100 smaller ones.
    • Proposed an idea and wrote a hybrid mobile app that replaced the old native one completely, thanks to that we had only one codebase and team instead of three (web, Android, iOS).
    • Conducted 57 technical in-person interviews, introduced online coding tests which more than 1000 candidates took, devised a method for auto grading, introduced employee referral scheme that brought more than 5 excellent new employees to the company.
    • Worked in a self-management setting in a period of a rapid development (from 28 to over 90 employees), contributed to Smarkets growth and culture.
    Technologies: BigQuery, PostgreSQL, AWS, GitLab, Jenkins, Docker, Flask, Bash, Linux, GNU, Haskell, Scikit-learn, Pandas, NumPy, IPython, SciPy, Python, Machine Learning
  • Cohort Member

    2015 - 2015
    Entrepreneur First
    • Accepted to the EF4 cohort consisting of 36 top tech people throughout Europe. There were 1200 applicants.
    • Collaborated with other members to conceptualize ideas.
    • Created SportsTracking proof of concept, an automatic extraction of statistics from sport videos using image recognition (Python, OpenCV).
    • Built prototype of BitVisual, a visualization of Bitcoin transactions (Neo4j graph database).
    • Developed first version of, a marketplace for translators (Scala, Play Framework).
    Technologies: Scala, Bitcoin, Neo4j, OpenCV, Python
  • Software Engineer

    2014 - 2015
    • Implemented core functionalities of Store Intelligence Android application in a team of 4.
    • Developed features for identity system for Flemish Government using Wicket (Java) in a team of 5.
    • Fixed several reported issues in the back-end of large Java EE system for Polish Ministry of Health.
    • Built a mobile hybrid application written in AngularJS and packed with Cordova for Android. Introduced Jenkins for automatic builds, which saved us about 5% of time everyday and resulted in less context-switching.
    • Conducted video-recorded, 1-hour Brown Bag Seminar titled "Android: basics, tips & tricks" to an audience of 30 people.
    • Co-organized HP Developer Day, brand-new, one-day programming competition for Polish developers. 2014 event gathered 40 selected participants and met with a very positive feedback.
    Technologies: Jenkins, Android, Java
  • Android Freelance Developer

    2012 - 2012
    • Gathered requirements, met and communicated with a client.
    • Implemented Android financial application which provided live share and corporate bond prices, plus a list of company announcements, dedicated to the Maltese listed market.
    • Advised and deployed finished product to the Google Play market.
    Technologies: Java, Android
  • Software Engineer Intern

    2011 - 2011
    • Implemented part of S Pen Library and developed demo app.
    • Wrote a tutorial + an exemplary game showing how to use the camera in Samsung Linux Platform (now Tizen).
    Technologies: Java, Android, C++, C
  • Junior Programmer

    2009 - 2009
    • Joined a startup (2 people at that time) to learn while developing websites such as and
    Technologies: Drupal, PHP, JavaScript, CSS, HTML


  • Game Tree Search Algorithms (Development)

    C++ library for AI bot programming, useful in competitions.

  • Shield for Clash of Clans (Development)

    Winner of Hack & Tell #2 London:

    Utility/hack for Clash of Clans, one of the most popular mobile games ever. It received 1000 installs after just 12 days and another 1000 installs after only 6 days through word of mouth between players. So far it has been installed on 200,000 devices in the world and counting.

  • Swipe Master 2: Space (Development)

    Android game developed over the course of a year as a personal project. Swipe Master has been installed on more than 30,000 devices in the world. It wasn't our primary goal, fun and learning were, but we even earned some money on ads.

  • ++C Programming Language (Development)

    Dynamically typed C. I also made string manipulation more convenient by making the string a built-in type. Also removed the need for declarations being before definitions, which is annoying in original C.

    For proof of concept, I wrote ++C to C++ translator (in C++, using Flex and Bison).

  • 10th (out of 4014) in Halite 3 (Other amazing things)

    During 3 months of competition, I created an AI bot in C++ that reached top 10.

  • 4th (out of 880) in Battle of Bots #3 (Other amazing things)

    During 1 week of competition, I created an AI bot in C++ that reached 4th place.

  • 7th (out of 2700) in IndiaHacks: Bot Challenge (Other amazing things)

    During 1 week of competition, I created an AI bot in C++ that reached 7th place.

  • Distinction on Engineer's Thesis from Warsaw University of Technology (Other amazing things)

    Thesis title: "Tool for detecting similar program code fragments."

  • Top 3% Overall on Stack Overflow (Other amazing things)

    Sorted by reputation points I'm in top 9000 users.

  • Our NIPS 2017: Learning to Run Approach (Other amazing things)

    For three months, from July to November 13, a friend and I participated in the NIPS 2017: Learning to Run competition. In this publication, we describe our experience.

    Skills: Deep reinforcement learning, TensorFlow, physics-based simulation

  • A Deep Dive into Reinforcement Learning (Publication)
    Machine learning and artificial intelligence are popular topics, vast domains with multiple paradigms to solve any given challenge. In this article, Toptal Machine Learning Expert Adam Stelmaszczyk walks us through implementing deep Q-learning, a fundamental algorithm in the AI/ML world, with modern libraries such as TensorFlow, TensorBoard, Keras, and OpenAI Gym.


  • Languages

    C++, Python, Java, SQL, R, C, HTML, CSS, JavaScript, PHP, Octave, Assembler x86, Bash, Scala, Haskell
  • Frameworks

    JUnit, Swagger, Bootstrap, Django, Boost, Flask, Play Framework, Caffe
  • Tools

    GitLab, Shell, Git, OpenAI Gym, Jenkins, PDB, GDB, Vim Text Editor, PyCharm, IPython, BigQuery
  • Paradigms

    Data Science, Object-oriented Programming (OOP), Continuous Integration (CI), Test-driven Development (TDD), Unit Testing, REST, Testing, Functional Programming
  • Platforms

    Linux, Drupal, Google Cloud Platform (GCP), Heroku, Amazon Web Services (AWS), Docker, Android
  • Other

    Game Theory, Optimization, Reinforcement Learning, Evolutionary Algorithms, Neural Networks, Software Development, Machine Learning, Deep Learning, Data Structures, Artificial Intelligence (AI), Algorithms, Genetic Algorithms, Research, Software Engineering, Bitcoin, Statistics, Mathematics, GNU, AWS, Deep Reinforcement Learning, Monte Carlo, Facebook Ads, Google Ads, Compilers
  • Libraries/APIs

    Keras, TensorFlow, NumPy, Pandas, Standard Template Library (STL), Scikit-learn, Matplotlib, SciPy, OpenCV
  • Storage

    MySQL, PostgreSQL, Neo4j, Google Cloud, MongoDB
  • Industry Expertise



  • Progress towards a Ph.D. in Artificial Intelligence, Deep Reinforcement Learning
    2017 - 2018
    University of Warsaw - Warsaw, Poland
  • Master's degree in Artificial Intelligence
    2013 - 2014
    Warsaw University of Technology - Warsaw, Poland
  • Engineer's degree in Computer Science
    2009 - 2013
    Warsaw University of Technology - Warsaw, Poland
  • Engineer's degree in Computer Science
    2011 - 2012
    University of Malta - Malta


  • Certified Professional Java 6 Programmer (OCPJP), 98% score

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