Java Pathfinder Inspector

In the summer of 2016, I participated in the Google Summer of Code program, during which I updated and significantly improved the Java Pathfinder Inspector.

Java Pathfinder (JPF) is a framework for formal checking of Java programs. Its core consists of a virtual machine for Java bytecode, running itself on Java; this allows JPF to instrument the code and provide its own functionality for critical instructions. JPF is very extensible and many modules exist for various kinds of verification such as symbolic execution. JPF Inspector is one such JPF module that focuses on debugging capability.

JPF Inspector is a tool for inspection and control of Java Pathfinder execution. It supports breakpoints and single-step execution (forward and backward) at different levels of granularity, and it allows the user to examine and modify program state (threads, call stacks, and heap objects). Unlike with standard debuggers (GDB), it is also possible to control thread scheduling explicitly.

This is the first software engineering project for which I received actual money.

It is programmed in Java.

It was created at the age of 23, in 2016.


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Oracion Online

Oracion Online is an online collectible card game for one or two players. It is in Czech only. It was created as a school project in the summer of 2016.

I invented the game Oracion, in its paper form, in 2009 for my Scout group and in the years 2009-2011 I used it in my patrol as a motivation element.

Oracion is a simple card game. Each round, each player plays a creature card, attaches tool cards or uses special actions, and then rolls dice. The number and kind of dice is determined by cards. The player who rolls the higher total “defeats” the opponent’s creature. The first player to defeat four of their opponent’s creatures wins the game.

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RFC: Protocol for initiation/termination of dialogue

Abstract: Many people sometimes wish to talk to other via instant messaging applications about their lifes, news, common interests and other topics without having important information to tell and without wanting to make a request (we will call these conversations “chats”). However, it may be difficult to find out whether your interlocutor wants to chat or would prefer to end the conversation because we encounter problems related to courtesy. For these reasons, we present a new protocol for chats that could save time for both interlocutors and help them lead the conversation for exactly as much as they both desire.

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World Romantic Relationships Authority

Sylvia was living in an unsanctioned relationship.

It wasn’t the fact that she was dating a girl that was bothering the World Romantic Relationships Authority. No, same-sex relationships had been sanctioned decades ago and were commonplace. The problem was that Sylvia was also dating a boy.

This was not a problem in itself. The WRRA could be more aptly named the World Romantic Relationship Advisory – it didn’t make laws, it offered recommendations. But even though it wasn’t illegal not to follow the WRRA’s guidance, it still felt wrong somehow and Sylvia couldn’t wait to be back in full compliance with the Authority’s recommendations.



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The Deadlock Empire

The Deadlock Empire is a programming puzzle game created in a team with Michal Pokorný for the 2016 Hack Cambridge hackathon.

In the game, the player assumes the role of a computer scheduler. In each level of the campaign, the player sees two or three threads of a computer program written in C#. He must then step through the program, performing context switches as he deems appropriate in order to demonstrate that the program contains bugs in its parallelism code.

For example, the player might simulate an execution order such that two threads enter a critical section at the same time or that results in a deadlock.

The game won the 1st place at the hackathon. In addition, we won two auxiliary prizes – Improbable‘s prize for “the best gaming/VR hack” and Bloomberg‘s prize for “most interesting project”.

The game is programmed in Javascript.

We created the game at the age of 23, in 2016.

Play online:


  • Learn parallel programming by playing a game
  • A story-based campaign – slay dragons, master concurrency!
  • Over 15 levels
  • Over 6 different synchronization primitives

Download Source Code:


Skauting by měl znát svoje principy.

V prosincovém čísle časopisu Skautský svět je esej od Mukókiho, vůdce ILŠ Collegium, zvaná “Tři základní principy skautingu a chvála nedefinovanosti”, ve kterém říká, že nejen povinnost k Bohu, ale i ostatní dva principy jsou málo definované, ale že tato nedefinovanost principů je dobrá věc, kterou bychom neměli měnit. Tento článek je reakcí na Mukókiho esej, ve které se snažím ukázat na chyby v jeho argumentaci a proč bychom stejně měli definovat, co myslíme povinností k Bohu.

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Fluttershy’s Hearthswarming Adventure

Fluttershy’s Hearthswarming Adventure is a text adventure game created for the Christmas of 2015. This is a fan game.

This is my second Windows parser-based interactive fiction. This means that there are no graphics to speak of – that takes place in your imagination. Instead, surroundings and events are described and you interact with the world by typing commands. But do not worry: It is not as difficult as old school games are. There is a suggestion system that will help find the commands you need and the game is set up in a way that you cannot truly lose.

The story itself is about the journey of Fluttershy to the depths of the Everfree in search of a magical artifact known as the Emotion Orb. She encounters animals, other ponies, obstacles and puzzles along the way. And in the end, it will be up to her to decide whether, and how, to change the Hearth’s Warming Eve festival for everypony, and for all time.

Remember that you are supposed to use a combination of the suggestion system and command typing. Usually, typing three letters of a word should be enough to eliminate most unwanted possibilities and then you use arrow keys and Enter to choose.

It is programmed in C# using the XNA framework.

I created the game at the age of 23, in 2015.


Download (Setup EXE, 8 MB):


  • Old-school text adventure
  • A cute heart-warming story
  • Hints of usable commands
  • Interaction with canon storyline
  • Affect the Hearth’s Warming Eve festival forever