Kamil Chmurzynski, Developer in Berlin, Germany
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Kamil Chmurzynski

Verified Expert  in Engineering

Bio

Kamil is a software engineer specializing in mobile and back-end development. He started programming in high school and eventually studied computer science at Oxford University. He's worked in many roles—from recently being a CTO to leading mobile app teams, performing unit and UI testing, and building back ends—never shying away from any challenge. Kamil recently completed his master's degree in AI and has done various AI projects, with his biggest side project being an automated AI trader.

Portfolio

Secure Staffing
Swift, Kotlin, iOS, Android, Java, Mobile App Development, SwiftUI...
Jordan Harris
Mobile Development, Architecture, Leadership, iOS, Android, Networking...
MVPExperience LLC
JavaScript, Android, Kotlin, Node.js, Next.js, NestJS...

Experience

  • Android - 10 years
  • Unity - 7 years
  • C# - 7 years
  • iOS - 7 years
  • Swift - 6 years
  • Kotlin - 5 years
  • JavaScript - 4 years
  • Artificial Intelligence (AI) - 2 years

Availability

Full-time

Preferred Environment

Git, Visual Studio, Unity, Android Studio, Xcode

The most amazing...

...project I've worked on is an automatic trading bot that uses AI models, which I've trained myself on cryptocurrency data.

Work Experience

Senior Software Developer | Mobile Applications

2023 - PRESENT
Secure Staffing
  • Developed iOS and Android apps that work like TikTok.
  • Ensured video streaming and content upload capabilities for users.
  • Built the app with deployment provisions for multiple target back ends, switching their assets quickly while maintaining a stable core and enabling the app to serve different client demographics.
Technologies: Swift, Kotlin, iOS, Android, Java, Mobile App Development, SwiftUI, Jetpack Compose, Full-stack Development, New Products, Application Engineering

Mobile Lead Developer (via Toptal)

2025 - 2025
Jordan Harris
  • Researched social media landscape in terms of apps and competitors.
  • Evaluated BlueSky as a backbone to build a new social media product around.
  • Created a product launch plan for the tech pipeline.
Technologies: Mobile Development, Architecture, Leadership, iOS, Android, Networking, Decentralized Systems, Full-stack, Flutter, React Native, Swift, Kotlin

Chief Technical Officer (CTO)

2022 - 2024
MVPExperience LLC
  • Worked on the vision and plan for an online casino platform with real dealers connected via webcams. Dealt with day-to-day technical problems that the company faced.
  • Was a board member negotiating deals with casinos in Las Vegas.
  • Led a small team to develop multiple client-facing apps, including web and mobile apps (Android). The apps allowed users to play games as part of a multi-video room led by a dealer.
  • Created back-end infrastructure and extra web apps to help organize events.
  • Communicated with a bespoke gambling table manufacturer so the company had physical tables with NFC cards. Extra software was developed to integrate with the company's current systems.
  • Created a web app to be used by staff (dealers) to help when dealing with cards and to communicate with players.
Technologies: JavaScript, Android, Kotlin, Node.js, Next.js, NestJS, Near-field Communication (NFC), Agora, Video Chat, CTO, Leadership, Team Leadership, Technical Leadership, Remote Team Leadership, Full-stack Development, Accounting, Finance, Ledgers, Double-entry Bookkeeping, New Products, Blockchain, Cryptocurrency, Application Engineering, Cryptocurrency Trading, Blockchain & Cryptocurrency

iOS 3D Specialist

2023 - 2023
Hoodie Hoo
  • Developed an iOS app for viewing and customizing clothes for a textile production company.
  • Gave the app a real-life feel, ensuring users could view actual clothing in 3D, change the textures and colors, and add embroidery patches.
  • Communicated with the client to improve UI and UX.
Technologies: Augmented Reality (AR), 3D, 3D Animation, Swift, iOS, 3D Character Modeling, 2D to 3D, Mobile App Development, New Products

iOS Senior Developer

2023 - 2023
Mediflix
  • Developed a buffering solution for short-form videos.
  • Created a new architecture to replace the old legacy solution.
  • Introduced code generation for back-end APIs to be used for all clients.
Technologies: iOS, Video Streaming, Swift, JavaScript, TypeScript, Mobile App Development, New Products

Lead Senior Software Developer | Mobile and Back-end Architect

2022 - 2022
Boorio
  • Created a Unity 3D poker game with social features, including chat and invites, allowing gambling by buying crypto chips.
  • Developed a back end written in JavaScript to handle poker game players.
  • Built a back-end blockchain solution that managed players' payments and converted them into in-game chips.
  • Created admin portals to manage game configurations, player statistics, and payment information.
Technologies: Multiplayer, Blockchain, Git, JavaScript, Amazon Web Services (AWS), Clean Code, Amazon Cognito, Firebase, Full-stack, Software Engineering, Mobile Apps, Software, Games, REST APIs, Smart Contracts, AWS CLI, AWS SDK, NestJS, MongoDB, Mongoose, MongoDB Atlas, Node.js, TypeScript, Next.js, React, Amazon S3 (AWS S3), Project Management, GitHub, Startups, API Integration, Payment APIs, APIs, JSON, Back-end, Webhooks, WebSockets, Back-end Development, Cross-platform App Development, Mobile Applications, Mobile Architecture, HTML, CSS, Integration, Leadership, DevOps, Native Mobile Apps, Cross-platform, Microservices, Cloud, Web Development, Web3.js, Android, Mobile App Development, iOS, Team Leadership, Remote Team Leadership, Full-stack Development, Accounting, Finance, Ledgers, Double-entry Bookkeeping, New Products, Cryptocurrency, Asyncio, Application Engineering, Cryptocurrency Trading, Blockchain & Cryptocurrency

Lead Senior Mobile Developer | Architect

2021 - 2022
Paid Workout
  • Created an iOS and Android app to encourage users to exercise and undertake fitness challenges. They can use the app's tokens or real cash to compete against others or specific score targets to win money and purchase fitness-related products.
  • Implemented a feature that allows users to participate in classes run by coaches and watch workout videos while the app measures their performance.
  • Integrated the app with HealthKit, Google Fit, and Fitbit to ensure the app got the correct data. The mobile apps also used location and distance tracking for one type of challenge.
Technologies: iOS, Swift, Swift 5, Android, Kotlin, HealthKit, Google Fit, Fitbit API, Apple Watch, Location Services and Maps, Xcode, Git, Android Studio, Mobile Apps, Software Engineering, Architecture, Software, Mobile, Wearables, WatchOS, Android SDK, REST APIs, SwiftUI, Clean Code, Firebase, Mixpanel, Multiplayer, Project Management, GitHub, Startups, Geolocation, API Integration, Payment APIs, JSON, Webhooks, iOS SDK, iOS Native Libraries, Cross-platform App Development, Mobile Applications, Location Services, GPS, Mobile Architecture, Integration, AVFoundation, Leadership, Native Mobile Apps, Cross-platform, Microservices, Cloud, Mobile App Development, New Products, Application Engineering

Lead Senior Mobile Developer | Architect

2020 - 2020
Helpar
  • Organized code architecture for an Android project to be viable for production.
  • Created UI solutions to ensure long-term productivity.
  • Composed documentation to describe the back-end API.
  • Implemented video and audio call solutions using Agora.
Technologies: iOS, ARKit, Firebase, Kotlin, Android, Amazon API Gateway, Git, Android Studio, Full-stack, Mobile Apps, Minimum Viable Product (MVP), Software Engineering, Architecture, Software, Mobile, Android SDK, REST APIs, Clean Code, Agora, Technical Leadership, Project Management, GitHub, Bitbucket, Startups, Geolocation, API Integration, QR Codes, JSON, WebSockets, Video Streaming, Cross-platform App Development, Mobile Applications, VoIP, Mobile Architecture, Near-field Communication (NFC), Integration, Leadership, DevOps, Native Mobile Apps, Cross-platform, Microservices, Cloud, Agile, Mobile App Development, New Products, Software as a Service (SaaS), Quizzes

Lead Senior iOS Developer | Architect

2019 - 2019
Calibrr
  • Created a proof-of-concept iOS app for social account management.
  • Made an OpenAPI (Swagger) spec file that documented the back-end API.
  • Built an AWS-based back end to handle app requests.
  • Integrated social network SDKs—Facebook, Twitter, and Snapchat—to use with social profiles within the app.
  • Implemented geolocation services in the app that allowed user interactions.
Technologies: Mobile App Development, Amazon Web Services (AWS), Amazon DynamoDB, Amazon Cognito, AWS Lambda, Swift, iOS, Xcode, Amazon API Gateway, Git, Full-stack, Mobile Apps, Minimum Viable Product (MVP), Software Engineering, Architecture, Software, Mobile, REST APIs, Clean Code, Project Management, GitHub, Startups, Geolocation, API Integration, APIs, JSON, Back-end, Webhooks, Back-end Development, iOS SDK, iOS Native Libraries, Cross-platform App Development, Mobile Applications, Location Services, GPS, Mobile Architecture, Integration, Leadership, DevOps, Native Mobile Apps, Cloud, New Products

Lead Senior Mobile and Back-end Developer | Architect

2019 - 2019
RolloMotion
  • Created an iOS Swift and Android Kotlin app for requesting and tracking scooter rides.
  • Developed an internal iOS app to help with scooter management.
  • Created a Swagger and OpenAPI spec to be used as an API between the back-end and apps.
  • Built a back end based on AWS Lambda to support the customer-facing and internal apps.
  • Integrated various services, such as Stripe and Twilio.
Technologies: Mobile App Development, Amazon Web Services (AWS), Twilio, Stripe, Amazon DynamoDB, Amazon Cognito, AWS Lambda, Kotlin, Android, Swift, iOS, Xcode, Amazon API Gateway, Git, JavaScript, Android Studio, Microsoft Visual Studio, Test-driven Development (TDD), Agile Software Development, Full-stack, Mobile Apps, Minimum Viable Product (MVP), Software Engineering, Architecture, Software, Mobile, Android SDK, REST APIs, Clean Code, Node.js, TypeScript, Project Management, GitHub, Bitbucket, Startups, Geolocation, API Integration, Payment APIs, QR Codes, APIs, JSON, Back-end, Webhooks, Back-end Development, iOS SDK, iOS Native Libraries, Cross-platform App Development, Mobile Applications, Mobile Architecture, Near-field Communication (NFC), Integration, Leadership, DevOps, Native Mobile Apps, Cross-platform, Microservices, Cloud, Full-stack Development, New Products, Application Engineering

Lead Senior iOS Developer | Architect

2019 - 2019
Tellzme
  • Worked on an iOS app that was a chat and content-sharing platform.
  • Evaluated choices and made final decisions on architecture that transformed a prototype into a real-life product.
  • Created a simple back end on AWS and used Lambda to serve the app.
  • Implemented video, image, and audio-sharing capabilities.
  • Orchestrated an Android team to follow the design, patterns, and technical decisions first made on iOS.
Technologies: Mobile App Development, Firebase, JavaScript, AWS Lambda, Swift, iOS, Xcode, Amazon API Gateway, Git, Mobile Apps, Minimum Viable Product (MVP), Software Engineering, Architecture, REST APIs, Software, Mobile, Android SDK, Clean Code, Technical Leadership, Project Management, GitHub, Startups, API Integration, APIs, JSON, iOS SDK, iOS Native Libraries, Mobile Applications, Mobile Architecture, Near-field Communication (NFC), Integration, Leadership, Native Mobile Apps, New Products, Software as a Service (SaaS)

Lead Senior Mobile Developer | Architect

2017 - 2019
HomeMD Technologies
  • Created an iOS medical app with Swift, including an EMR, video, and chat messaging system (Play.google.com/store/apps/details?id=ca.homemd.homemd).
  • Built an Android app that was one-on-one with the iOS app using Kotlin.
  • Wrote unit tests to make sure the app was bug-free. The app had to be HIPAA-compliant and secure, as it dealt with medical data.
  • Composed UI tests to make sure iOS and Android apps performed as expected. Created an automated system to run these UI tests on real devices and check if the apps perform as expected.
  • Set up Travis CI to run unit tests and deploy and manage the build process of the apps.
  • Configured Mixpanel and tracking funnels to analyze the apps' performance, such as drop-out ratios.
  • Used Twilio for chat, SMS for text, and VoIP for video messaging.
Technologies: Mobile App Development, Firebase, Mixpanel, Xamarin, C#, Travis CI, JavaScript, Unit Testing, Kotlin, Android, iOS, Swift, Xcode, Git, Android Studio, Full-stack, Mobile Apps, Software Engineering, Architecture, Software, Mobile, Android SDK, REST APIs, Clean Code, MongoDB, Node.js, TypeScript, React, Amazon S3 (AWS S3), Technical Leadership, Project Management, GitHub, Startups, API Integration, Payment APIs, HIPAA Compliance, Stripe API, Stripe Checkout, Stripe Subscriptions, APIs, JSON, Back-end, WebSockets, Video Streaming, Back-end Development, iOS SDK, iOS Native Libraries, Cross-platform App Development, Mobile Applications, VoIP, Mobile Architecture, HTML, CSS, Integration, Jetpack Compose, Realm, Alamofire, Leadership, Native Mobile Apps, Cross-platform, Cloud, Agile, Web Development, Full-stack Development, New Products, Software as a Service (SaaS), Application Engineering

Unity Developer

2017 - 2017
ARSports
  • Developed essentially a Pokemon GO clone where a user catches football players.
  • Built a real-time 3D map view for a user to walk in.
  • Created an AR scene where the user could catch football players and appear in the same room as them.
  • Developed a Parse back end for the app to generate football players on the map and maintain user state.
  • Helped to create a system where it was possible to easily modify players' appearance.
Technologies: Unity3D, Parse, Augmented Reality (AR), Unity, Git, Full-stack, Mobile Apps, Minimum Viable Product (MVP), Software Engineering, Architecture, Software, Games, Mobile, Clean Code, Multiplayer, GitHub, Startups, Mobile Applications, Mobile Architecture, Game Development, Video Gaming, Integration, Game Design, 3D Games, New Products

iOS Swift Developer

2017 - 2017
Monstar Lab Singapore
  • Processed images to find faces—created algorithms that would be able to detect faces and face edges.
  • Analyzed face data to crop accurate faces from images.
  • Came up with the user UI that improves face detection and cropping.
  • Applied toon shaders to make faces look like cartoons.
  • Created a cartoon app that takes a user's face and puts it into the cartoon so that the user becomes the main character of the comic.
Technologies: Mobile App Development, Cartoons, Image Processing, iOS, Swift, Xcode, Git, Mobile Apps, Minimum Viable Product (MVP), Software Engineering, Architecture, Core Animation, Software, Mobile, Algorithms, Clean Code, GitHub, iOS Native Libraries, Mobile Applications, Mobile Architecture, Integration, Native Mobile Apps, New Products

Game Developer

2017 - 2017
Escape the Room NYC
  • Created new puzzles for the Escape the Room game, which would be used in a physical escape room setting.
  • Made use of external specialized hardware that is used inside escape rooms that control the game.
  • Built multi-display views that give the impression of being in a submarine.
  • Developed a periscope view that works like a 3D sonograph.
Technologies: Unity3D, JavaScript, Shaders, Unity, Git, Software Engineering, Software, Games, Clean Code, Multiplayer, GitHub, Game Development, Video Gaming, Integration, Game Design, 3D Games, New Products

Unity Developer

2017 - 2017
Speechbytes, LLC
  • Took an existing codebase and wrote from scratch a whole game that helps children with speech impairment improve their speech.
  • Made the game entirely configurable to work with Parse asynchronously to avoid blocking the user experience.
  • Used physics to make small minigames that oscillate around moving objects.
  • Developed an easy asset deployment system to extend the game further without any code.
  • Created loads of assets that were used in different game modes.
Technologies: Unity3D, Mobile App Development, Drawing, Parse, C#, Unity, Git, Full-stack, Mobile Apps, Minimum Viable Product (MVP), Software Engineering, Architecture, REST APIs, Core Animation, Software, Games, Mobile, Clean Code, GitHub, Startups, Mobile Applications, Mobile Architecture, SQL, Game Development, Video Gaming, Integration, Cross-platform, Cloud, New Products

Senior Engineer

2013 - 2017
Wooga
  • Worked on Diamond Dash, an arcade mobile game for iOS in Objective-C.
  • Built tools and frameworks to speed up game making using Objective-C for iOS, Java for Android, and C# for Unity.
  • Developed a game similar to Clash of Clans by Supercell; handled it from conception to production using Unity and C# and served as the lead programmer.
  • Interviewed candidates and improved the interview process at the company.
  • Worked on a farming simulator similar to Hay Day using Unity and C# as the senior lead programmer.
Technologies: Unity3D, Mobile App Development, JavaScript, Android, iOS, Java, Objective-C, Unity, C#, Xcode, Xamarin, Git, Microsoft Visual Studio, Test-driven Development (TDD), Agile Software Development, Full-stack, Mobile Apps, Minimum Viable Product (MVP), Software Engineering, Architecture, REST APIs, Core Animation, Software, Games, Mobile, Algorithms, Android SDK, Clean Code, Multiplayer, Technical Leadership, Project Management, GitHub, API Integration, JSON, 3D, Cross-platform App Development, Mobile Applications, Mobile Architecture, Python, SQL, Game Development, Video Gaming, Integration, Leadership, Native Mobile Apps, Cross-platform, Agile, Game Design, 3D Games, New Products, Software as a Service (SaaS)

Developer

2013 - 2014
OFC Poker Freelance Project
  • Created the concept and researched multiple ways of solving open-face Chinese poker games.
  • Wrote rules that led to the creation of a manual that helps a player play the poker variant live.
  • Developed an approximator program that produces approximations of the best plays for complex scenarios.
  • Created a solver program that solves the game for all late-game situations and gives appropriate play variants.
  • Built extensions to the program to be used with variants of open-face Chinese poker.
Technologies: Unity3D, C#, Git, Minimum Viable Product (MVP), Software Engineering, Architecture, Software, Games, Algorithms, Clean Code, GitHub, Game Development, Video Gaming, Integration, New Products

Software Engineering Intern

2011 - 2011
Ocado
  • Developed a chat application for the iPhone and iPad that works similarly to Skype.
  • Made the chat application work with an internal phone system that would track calls in real time.
  • Created test suites for the chat application and push sever.
  • Deployed a push server using Java to notify users of the chat app.
Technologies: Mobile App Development, Java, Objective-C, iOS, Xcode, Git, Microsoft Visual Studio, Agile Software Development, Mobile Apps, Minimum Viable Product (MVP), Software Engineering, Architecture, Software, Mobile, Algorithms, REST APIs, GitHub, API Integration, Mobile Applications, Mobile Architecture, SQL, Integration, Native Mobile Apps, New Products

Experience

Automated Cryptocurrency Trading Bot Using AI

This project had multiple parts, as it is an automated system that could communicate with brokers to automatically manage trades and perform actions based on signals, also serving as a system that could retrieve prices and aggregate signals to pass them onto the automatic trading system and finally, AI models trained on cryptocurrency data using the latest reinforcement learning methods that could give buy/sell signals that the previous two systems can use.

AI Companion/Girlfriend Chatbot

A web app chatbot that serves as a companion/girlfriend. Users can select the specs or characteristics of their companion, and based on these, the chatbot behaves in a specific way. Users can also request photos of the companion.

The chatbot was controlled by ChatGPT and later by Claude, whereas the picture generation was done using Stable Diffusion.

Everything was achieved by clever manipulation of contexts and prompt engineering.

Age of Trade

An unreleased economical simulation similar to Clash of Clans for iOS and Android devices.

Apart from a very novel gameplay idea, the game had a new semi-3D perspective and dynamic water canals and terrain generation. It was not yet fully optimized at the time but was already looking fantastic on mobile devices.

Role: Lead Developer

AI Project | Sentiment Analysis of Reddit Posts

A Python project that looked at Reddit posts from around the beginning of 2021 when GameStop (GME) was massively shorted by companies. Reddit users exploited this to create an unprecedented black swan event, and thousands of Reddit posts and comments were analyzed to see how sentiment affects stock prices. A bespoke LLM was needed to understand Reddit users' peculiar language, full of meme references and emojis.

Entitas - Open Source Entity Component System (ECS) Framework for C# and Unity

https://github.com/sschmid/Entitas
Entitas is the most popular open-source Entity Component System Framework (ECS) specifically made for C# and Unity. I helped with its development, created tutorials, answered community questions, and created various games using it.

Education

2023 - 2024

Master's Degree in Artificial Intelligence

Wroclaw University of Science and Technology - Wroclaw, Poland

2009 - 2013

Master's Degree in Computer Science

Oxford University - Oxford, United Kingdom

Skills

Libraries/APIs

REST APIs, iOS Native Libraries, Stripe, Parse SDK, Core Animation, Node.js, Stripe API, Alamofire, Web3.js, Asyncio, OpenAI API, HealthKit, Fitbit API, React, LSTM, Entity Framework

Tools

MonoDevelop, Eclipse IDE, SourceTree, Paint.NET, Xcode, Microsoft Visual Studio, GitHub, Bitbucket, Travis CI, Android Studio, TortoiseSVN, Git, Subversion (SVN), Amazon Cognito, AWS SDK, Agora, Mongoose, MongoDB Atlas, Stripe Checkout, Visual Studio, AWS CLI, ChatGPT, AI Prompts, Claude

Languages

JavaScript, Java, C#, Swift, Kotlin, Objective-C, Google Apps Script, Python, TypeScript, SQL, HTML, CSS, C, Scala, C++, PHP, Swift 5

Frameworks

Unity3D, Unity, iOS SDK, LibGDX, Android SDK, NestJS, Next.js, ARKit, SwiftUI, Flutter, React Native

Paradigms

Concurrent Programming, Agile Software Development, Extreme Programming, Unit Testing, Refactoring, Test-driven Development (TDD), Testing, Clean Code, Clean Architecture, Cross-platform, DevOps, Microservices, Agile, HIPAA Compliance, Entity Component System (ECS), Mobile Development

Platforms

iOS, Android, Mobile, Amazon Web Services (AWS), Xamarin, Parse, AWS Lambda, Mixpanel, Twilio, Firebase, Apple Watch, WatchOS, Blockchain

Industry Expertise

Project Management, Accounting, High-frequency Trading (HFT)

Storage

JSON, Amazon DynamoDB, MongoDB, Realm, PostgreSQL, NoSQL, MySQL, Amazon S3 (AWS S3)

Other

Mobile App Development, Architecture, Mobile Apps, Minimum Viable Product (MVP), Software Engineering, Software, Games, Algorithms, Technical Leadership, Startups, API Integration, QR Codes, APIs, WebSockets, Video Streaming, Cross-platform App Development, Mobile Applications, VoIP, Mobile Architecture, Game Development, Video Gaming, Integration, Leadership, Native Mobile Apps, Full-stack Development, Trading, Trading Bots, Time Series Data, New Products, Software as a Service (SaaS), Application Engineering, Software Development, Cryptocurrency Trading, Blockchain & Cryptocurrency, Augmented Reality (AR), Lambda Functions, Amazon Cognito User Pools, Amazon API Gateway, Full-stack, Multiplayer, Geolocation, Payment APIs, Stripe Subscriptions, Back-end, Webhooks, 3D, Back-end Development, Location Services, GPS, Artificial Intelligence (AI), Near-field Communication (NFC), AVFoundation, Cloud, Web Development, Game Design, 3D Games, Reinforcement Learning, Deep Reinforcement Learning, Finance, Ledgers, Double-entry Bookkeeping, Cryptocurrency, Quizzes, Drawing, Shaders, Image Processing, Cartoons, Google Fit, Location Services and Maps, Wearables, Smart Contracts, Artificial Neural Networks (ANN), Data Engineering, Machine Learning, Jetpack Compose, Long Short-term Memory (LSTM), LSTM Networks, Recurrent Neural Networks (RNNs), Sentiment Analysis, Large Language Models (LLMs), Open-source LLMs, 3D Animation, 3D Character Modeling, 2D to 3D, Statistics, Data Processing, Video Chat, CTO, Team Leadership, Remote Team Leadership, Chatbots, ChatGPT API, ChatGPT Prompts, Prompt Engineering, Stable Diffusion, Quantitative Finance, Quantitative Modeling, Networking, Decentralized Systems

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