Photo of Paweł Biernacki

Paweł Biernacki

Senior Engineer

Hi, I'm Paweł. I'm a senior software engineer with over 10 years of experience in web- and app development.

I love working on important problems and creating products that bring value and improve people's lives.


Staff Frontend EngineerDeltia GmbH

01.2023 - present
  • Deltia Platform

    A web application for analyzing, monitoring and improving operations on assembly lines.

    I'm working on a React SPA application, an analytical dashboard with lots of data visualizations using D3.js, and supporting the backend side with bugfixes and feature development. I'm also part of the product team responsible for understanding the needs of our customers and translating them into product requirements.

    • React.js
    • Radix UI
    • Tailwind CSS
    • D3.js
    • GraphQL
    • Python
    • Django
    • SQL
    • Docker

Senior EngineerXayn AG

07.2018 - 12.2022
  • Xayn Discovery Engine

    An open source on-device content recommendation system, a core component of the Xayn Private News Assistant mobile app.

    I've implemented a good chunk of communication layer between the app and core engine running in a long-lived Dart isolate and contributed to parts of the domain and infrastructure layers for storing user interactions used by the AI content ranking system.

    • Rust
    • Dart
    • Flutter
  • Remote Planning Poker

    A simple tool for remote teams to conduct estimation sessions.

    The purpose of this side-project was to gain exposure to Rust. I've implemented both frontend and backend, exchanging messages in real time between each other via WebSockets.

    • Rust
    • Yew
    • Axum
  • Xayn Search

    A privacy-focused mobile search engine and web browser.

    I was the lead Flutter engineer responsible for implementing major UI and state management features and parts of domain and infrastructure layers necessary for storing the history of user interactions needed for the AI content ranking model.

    • Flutter
    • Dart
  • Xayn Voice

    A proof of concept for voice recognition on mobile.

    I've implemented an interface to capture audio recordings, feature engineering for audio input, and integration of a custom Tensorflow Lite model via FFI bindings. That was a nice project to learn Dart, Flutter and some machine learning bits.

    • Flutter
    • Dart
    • Tensorflow Lite
  • Andy (formerly Intac)

    A set of Progressive Web Apps for accounting departments.

    As one of two frontend engineers, I was responsible for implementing two web applications for digitalizing invoices and reviewing cost centers inferred by the AI model. Both of the applications were communicating with RESTful APIs.

    • React.js
    • Material UI
    • Redux
    • PDF.js

Frontend DeveloperSenfino Sp. z o.o.

06.2017 - 05.2018
  • Medical Tales

    A web application used by medical professionals for tracking patient's medical history.

    I've implemented a frontend application for capturing input from medical records and examinations and displaying a history of patients' medical data as interactive graphs.

    • React.js
    • Chart.js
    • Redux
  • CYC Fitness

    A website and web application for a chain of indoor cycling studios.

    As one of two frontend engineers, I was responsible for implementing UI features for a spinning classes booking system.

    • React.js
    • Redux

Frontend DeveloperMMPro

01.2015 - 05.2017
  • AdmiralCloud

    A multimedia management system composed of many features including advanced search, video transcoding, image processing, video/audio transcripts, custom video player, etc.

    In a team of five engineers, I was responsible for implementing different UI features in the core application and smaller complementary apps such as press release showcase or dropzone for file uploads.

    • React.js
    • Flux
    • video.js


01.2012 - 12.2014
  • Various client projects

    Custom graphic design, branding, web-design and development for clients.

    Most of my clients were small and medium sized companies from OOH, energy, legal and financial sectors. I was responsible for everything, which is why I moved away from freelancing ;)

    • Adobe Photoshop
    • Adobe Illustrator
    • ProcessWire CMS/CMF
    • HTML
    • CSS