TK

Senior Software Engineer & Technical Consultant

I turn undocumented, complex systems into stable, deliverable products.

10+ years of full-stack experience across React, Vue, .NET and Node.js — based in Poland, working remotely with teams across the US, UK and Singapore.

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01 / About

I'm a Senior Software Engineer and Technical Consultant with 10+ years of experience, including running an independent technical consultancy since 2017. My track record spans React/TypeScript and Vue on the frontend, with C#/.NET, Node.js and SQL on the backend — most recently owning both the Vue and C#/.NET sides of a backend-driven enterprise application for four years. I specialize in taking ownership of complex, often undocumented systems and turning them into stable, deliverable products — guided by a simple principle: the better you understand a system, the less code you need to write.

10+
Years of experience
JavaScript
My second mother tongue
10,000h+
Hours of deliberate coding practice
1M+
Users reached through products I've helped ship

02 / Tech Stack

Tech Stack

Frontend
React
TypeScript
JavaScript
Vue 2/3
Redux
HTML5
CSS3
SCSS
Bootstrap
Backend
C#/.NET
Node.js
Express.js
SQL Server
MySQL
SignalR
Entity Framework
Tooling
Jest
React Testing Library
Cypress
Playwright
Git
Docker
Azure DevOps
GitHub Copilot
Also worked with
AngularJS
PHP
WordPress
Flutter
Vuex
Pinia
Redux-Saga

How I work

Backend-driven UI architectureAPI contract designState managementPerformance optimizationLegacy system modernizationAuthorization & permissions designCode reviewResponsive designAgentic development workflows

03 / Experience

Experience

  1. Technical Consultant & Software Engineer

    CURRENT
    Animality Foundation
    Mar 2026 – Present · Remote · Wroclaw, Poland

    Rebuilt an undocumented multi-app ecosystem into a maintainable, delivery-ready system.

  2. Lead Software Engineer

    SpecCheck (Caterpillar)
    Mar 2022 – Mar 2026 · Remote · Jacksonville, FL, USA

    Owned full-stack modernization of a backend-driven enterprise app; led the Vue 2→3 migration.

  3. Senior Frontend Developer

    Xcelirate
    Apr 2020 – Mar 2022 · Remote · Singapore / Barcelona

    Built reusable React components and scalable Redux state for a production social platform.

  4. Frontend Engineer

    Xcelirate
    Apr 2019 – Mar 2020 · Remote · Singapore

    Delivered a complete UI redesign with an incremental rollout and no downtime.

  5. Full Stack Software Engineer

    Desap
    Jun 2019 – Apr 2020 · Remote · Manchester, UK

    Built a real-time collaborative whiteboard with React, .NET and SignalR.

  6. Software Engineer

    bet365
    Apr 2017 – Jun 2018 · On-site · Manchester, UK

    Contributed to a custom framework for modernizing legacy applications.

+ 2 earlier roles (2015–2017) — Electrika Ltd, Bounce Castle Network

04 / Selected Work

Selected Work

Popup Optimization

Diagnosed why a popup felt broken despite working, and fixed it by removing a redundant backend query — not hiding it behind a loading skeleton.

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Vue 2 → Vue 3 Migration

Led an incremental migration of a backend-driven enterprise app, cutting the frontend codebase by ~50% with zero delivery downtime.

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Animality Foundation

Took ownership of an undocumented multi-app ecosystem after the previous team left, and rebuilt it into a maintainable, delivery-ready system.

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© 2026 Tomasz Koszkul. All rights reserved.