About Me

Driven, passionate, problem solver. I taught myself C++ to analyze financial time series using ML. Then it snowballed into .NET and countless other technologies. I’ve seen a lot, maybe even too much sometimes. I drew conclusions and now I focus on clarity, maintainability and impact.

Beyond my full-time work I develop the stock market analysis tool Stock-Today, I am CTO of Squizzu, I maintain several open source libraries and I write False Green, a blog about agentic AI pitfalls described by themself.

Technical Skills

  • C#12 years
  • Azure Cloud9 years
  • ASP.NET (Web API, Core)11 years
  • SQL + EF6 years
  • NoSQL (CosmosDB, Mongo)8 years
  • WPF in MVVM5 years
  • ML (ML.NET, Accord.NET, Keras, GPT API)8 years
  • AI-assisted development (Claude Code, Azure OpenAI)3 years

Technology

General
OOP, microservices, (modular) monolith, SOLID, TDD, REST, Clean Architecture, DDD
Languages
C#, C++, Python, Ruby, R, JS, VB
Cloud
Azure (App Services, Service Bus, Azure AI Search, Azure ML, Azure OpenAI, Key Vault, CosmosDB, Blob and File Storage, Cache for Redis), Azure DevOps, Heroku
DevOps
Azure DevOps (Pipelines, Releases), GitHub Actions, Docker, Terraform, Kubernetes
Databases
MS SQL, CosmosDB, SQLite, Postgres, MongoDB + Atlas Search, Parquet
Message brokers
Azure Service Bus, RabbitMQ, MSMQ, Kafka
.NET ecosystem
ASP.NET Core, WPF (MVVM, Telerik), ML.NET, Entity Framework, ADO.NET, WinForms, WebForms
Observability
Grafana, Application Insights, OpenTelemetry, Datadog
Testing
Postman, Burp, NUnit, xUnit, MSTest, Vegeta, NBomber, Playwright, SoapUI, Bruno
Project management
Azure DevOps, Jira, Trello, Notion
Machine learning
Azure OpenAI, ML.NET, Azure Machine Learning, Accord.NET, EmguCV, Keras
Low code / no code
Microsoft Power Apps, Dataverse, Microsoft 365 integrations
Source control
Git, Subversion, TFS, GitHub, Bitbucket
Preferred AI stack
Claude Code CLI, superpowers, Matt Pocock's skills, my own skill set
Other
Swagger, Zendesk, Cloud9, SonarCloud, GhostDoc, ReSharper, JSON, XSLT, XSD

Soft Skills

  • Integrity
  • Persistence
  • Autonomy
  • Creativity
  • Deep Focus

Education

  • Jagiellonian University - Psychology - Master 2009 - 2016
  • Polish/French Bilingual High School 2004 - 2008

Work Experience

  1. StoneX Financial Services - Senior Software Developer since 2025

    Migrating legacy client-facing cloud applications to a modular monolith in Domain-Driven Design and Clean Architecture. Removed the code review bottleneck in the team's SDLC and optimized DataGrid search by 10x. AI-first development with the emphasis on end-to-end and integration tests.

  2. Happy Team - Senior Software Developer 2025

    Built the backend for a .NET MAUI mobile app from the ground up: a serverless API in Azure Functions talking to CosmosDb, a proxy service, and the whole supporting infrastructure described in Terraform. Designed for testability, ease of maintenance, performance and scalability.

  3. Seville More Helory Polska - Senior Software Developer 2020 - 2025

    Implemented, documented and unit tested GIT inspired document version control in C# ASP.NET / CosmosDb / Azure AI (Cognitive) Search + Azure Service Bus + Redis + SignalR + SonarCloud. Cut Azure Redis Cache costs by implementing an intermediate cache layer based on CosmosDb. Designed and implemented the backend for a bespoke legal Q&A, FAQ, provisions, rights and clauses lifecycle management process that secured a key client, increasing company revenue by over 10%. C# Web.API + CosmosDb + React + Service Bus.

  4. Jagiellonian University - Researcher 2019 - 2020

    I developed an electroencephalogram (EEG) monkey brain activity classifier and an Arduino-based tactile stimulator. The stimulator features 2 gloves with 5 effectors, each controllable separately via COM source. For classification I used Python's Keras, achieving accuracy above 0.8 after applying FFT and other transformations to raw EEG time series source.

  5. Open GI - Software Developer 2017 - 2019

    Took part in modernizing a legacy desktop monolith by splitting and migrating logic into microservices while heavily unit-testing existing functionality, moving slowly by first hosting the old Windows application over Azure Virtual Desktop. Used ASP.NET Core, WCF, RabbitMQ, WWF, Azure IaaS, MongoDB, MS SQL, SonarQube, Docker.

  6. Transactor Poland - Junior Software Developer 2014 - 2017

    Started as a Junior Software Developer and was promoted to Regular after successfully delivering the first project — a WPF business intelligence application that aggregated data from multiple APIs, providing significant value to the customer at a low cost. C#, WPF, XSLT, XSD, SQLite, MS SQL. Developed, refactored, bug fixed, and unit tested an end-to-end insurance lifetime management system. Participated in multiple third-party integrations, including payment providers and data enrichment services, ensuring interoperability between systems. T-SQL, WCF, ASP.NET API, WPF, Windows Forms, VB.NET, MS SQL, WWF, SignalR, SOAP, Azure DevOps (VSTS at the time), Trello, Jira and Zendesk.

  7. IGE+XAO - Intern 2014

    Implemented a database-wide undo T-SQL procedure ahead of schedule, using a C# code generator driven by the table schema. Maintained a C++ CAD desktop app.

Other Projects

Stock market quant and fundamental analysis tool Stock-Today, giving daily updated insights for both speculative trading and long-term investing. Hosting: Azure, back end: C#, MS SQL, ML.NET, front end: pure HTML, CSS and JS.

I am CTO of Squizzu, a tech quiz platform built with React and C# leveraging generative AI. I architected and implemented most of the data model, set up CosmosDB and Key Vault integrations and I own the Azure OpenAI integration.

I write and publish False Green, a blog about verification that looked green and wasn't — each post is a real incident where a check passed while the system stayed broken. Astro static site, deployed to Azure Static Web Apps by GitHub Actions over Terraform-managed infrastructure.

I maintain a public set of Claude Code skills — over 30 repeatable workflows for code review, triage, handoff and release hygiene, installable as a Claude Code plugin.

Throughout my journey I have also explored other startup ventures, including an online course platform and a calendar tool built with Power Apps. While these projects didn't achieve long-term success, they provided valuable lessons and skills such as proficiency in the Power Platform.

Notable open source packages I maintain:

  • LoggerLite — A lightweight logging framework supporting JSON, XML, YAML, and console output, with built-in debouncing.
  • OnTheFlyStats — Allows on-the-fly computation of statistics such as means and variance, with O(1) access.
  • Extensions.Standard — A collection of extension methods for common programming tasks such as interpolation and partitioning.
  • ProgressReporting — A library for estimating completion time and reporting progress in iterative operations and data transfers.
  • StocksData — A .NET Standard library for simulating stock trading strategies against historical market data. Published on NuGet as the Stocks.Data.* packages.

These and other packages are available on NuGet.org.

My GitHub activity

Languages

  • Polish - native
  • English - C2
  • French - B2

Conferences & Trainings

  • 2025 - Niebezpiecznik - Attacking and Securing Web Apps
  • 2021 - MEGA Sekurak Hacking Party
  • 2020 - AzureDay
  • 2019 - MEGA Sekurak Hacking Party
  • 2018 - .NET DeveloperDays
  • 2014 - Scrum Workshop

Additional Information

  • Category B driving license.
  • Knowledge in psychology.
  • Hobbies: economics (personal finance and quantitative analysis), board games, squash, running, bodybuilding.

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