Daniel Bigos, Developer in Warsaw, Poland
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Daniel Bigos

Verified Expert  in Engineering

Software Developer

Warsaw, Poland
Toptal Member Since
March 3, 2021

Daniel is a software engineer focused on functional programming. He gained professional experience in blockchain technology while working on large projects such as Golem. He also has experience in building startups and designing products, as he is a co-founder of DoxyChain, a blockchain-based document management system.


Blockchain, Hyperledger, Elixir, Docker, Angular...
Blockchain, Tendermint, Docker, Docker Compose, Elixir
Python, Blockchain, Ethereum, Angular, TypeScript, Rust, Waffle, Docker...




Preferred Environment

MacOS, Jira, Confluence, Bitbucket, Visual Studio Code (VS Code), Slack, Terminal

The most amazing...

...thing I've achieved is winning second place at the Global Legal Hackathon in Poland in 2019. Our idea evolved into a startup called DoxyChain.

Work Experience

Blockchain Developer

2020 - PRESENT
  • Prepared a matching engine for market offers such as asks and bids in Elixir.
  • Made a simple front-end demo application for the client in Angular.
  • Developed a communication layer between DAML on Fabric and back-end applications in Elixir.
  • Prepared HLF infrastructure, including channels, organizations, and external chain code.
Technologies: Blockchain, Hyperledger, Elixir, Docker, Angular, Digital Asset Modeling Language (DAML)

Co-founder | Software Engineer

2019 - PRESENT
  • Made a simple demo of the document management system for marketing purposes, using Elixir, CircleCi, and React.
  • Prepared the back-end side of the document management system for special document types for one of the Polish legal chambers using Elixir and Tendermint.
  • Built the blockchain part of the SaaS document management system available to every user in Elixir and Tendermint.
Technologies: Blockchain, Tendermint, Docker, Docker Compose, Elixir

Software Engineer

2018 - 2020
  • Developed a proof of concept for spreading transcoding tasks on Golem in Python.
  • Prepared a transcoding demo, including the back end in Python and Django and front end in Angular, that connects to Golem and spreads transcoding tasks.
  • Wrote a payment driver for New Golem (YAGNA) in Rust. The driver connects to the Ethereum blockchain and makes ERC-20 token payments.
  • Made a proof of concept of zkSync payments for the New Golem in JavaScript.
Technologies: Python, Blockchain, Ethereum, Angular, TypeScript, Rust, Waffle, Docker, Docker Compose, Django, JavaScript

Junior Software Engineer

2017 - 2018
  • Made a new library for parsing XML files in C++11.
  • Tracked and fixed bugs in applications processing data files such as XML, CSV, and TXT.
  • Developed a database schema and connector app for specific energy industry data.
Technologies: C++11, Boost, Oracle Database, SQL

DoxyChain System

DoxyChain is a blockchain-based document management system. I was responsible for the blockchain side of the product and implementing the whole protocol and communication with Tendermint. The protocol covers user management based on X.509 certificates and document lifecycle management (smart contracts).
2019 - 2022

Master's Degree in Computer Science

Warsaw University of Technology - Warsaw, Poland

2015 - 2019

Bachelor's Degree in Computer Science

Warsaw University of Technology - Warsaw, Poland


Certified Scrum Master



Scrum Fundamentals Certified



Docker Compose, Jira, Confluence, Bitbucket, Slack, Terminal


Blockchain, Ethereum, Hyperledger Fabric, Docker, Oracle Database, Hyperledger, MacOS, Visual Studio Code (VS Code)


Tendermint, Angular, Boost, Django


Elixir, Rust, TypeScript, Python, C++11, SQL, JavaScript


REST, Functional Programming, DevOps, Scrum


Software Development, Web Programming, Software Design, IT Project Management, Software Architecture, Waffle, Digital Asset Modeling Language (DAML)

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