Josef Sevcik, Developer in Zürich, Switzerland
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Josef Sevcik

Verified Expert  in Engineering

Bio

Josef is a highly flexible consultant with extensive experience in distributed systems, both from telecommunication and blockchain environments. He can assume various roles based on actual business needs - product owner, architect, analyst, developer, or team leader.

Portfolio

Flashlabs
Solidity, Azure IoT Hub, Apache Kafka, React, JavaScript, Node.js, Architecture...
UBS
Java, C++, IBM MQ, TIBCO Rendezvous, APIs
Growth DeFi
Blockchain, Solidity, Ethereum, Bitcoin, Ethereum Smart Contracts...

Experience

  • Bash Script - 10 years
  • C++ - 9 years
  • Integration - 7 years
  • System Architecture - 6 years
  • Blockchain - 3 years
  • Python - 3 years
  • Peer-to-peer Networking - 2 years
  • High-frequency Trading (HFT) - 1 year

Availability

Part-time

Preferred Environment

Linux, Clang, GCC, Python, CLion

The most amazing...

...thing I've developed is Decent, the blockchain-based content distribution platform, which I've driven from early protocol design to launch.

Work Experience

Senior Software Engineer

2021 - 2022
Flashlabs
  • Developed a non-fungible token (NFT) marketplace using both ERC1155 and ERC721 standards.
  • Architected a digital asset exchange—an NFT-backed marketplace for IoT data streams that include full access control and "Stream Lambdas," functions processing data streams.
  • Managed and coached junior team members and acted as the CTO's right hand.
  • Led the customized deployment of the marketplace for a customer from the metaverse industry.
Technologies: Solidity, Azure IoT Hub, Apache Kafka, React, JavaScript, Node.js, Architecture, Non-fungible Tokens (NFT), Ethers.js, Team Leadership, HTML, Jira, APIs

Senior Software Engineer

2020 - 2021
UBS
  • Upgraded the number of legacy messaging queues bridges (Tibco/IBM), some of them more than ten years old. The project aimed to introduce SSL-secured connections in all inter-system communication.
  • Managed various stakeholders (system owners) and planned the migrations.
  • Took over the old source codes for the bridges and create updated builds.
Technologies: Java, C++, IBM MQ, TIBCO Rendezvous, APIs

Blockchain Engineer

2020 - 2020
Growth DeFi
  • Worked on integration with various DEXs (decentralized exchanges) such as SushiSwap, Save, and Uniswap.
  • Reviewed and audited code provided by other team members.
  • Worked on liquidity mining logic, implemented in smart contracts.
Technologies: Blockchain, Solidity, Ethereum, Bitcoin, Ethereum Smart Contracts, Smart Contracts, Cryptocurrency, Blockchain Platforms

Blockchain Architect and Developer

2020 - 2020
Taraxa
  • Developed series of smart contracts and integrated them into a Python/Flask application for marinate.io.
  • Designed a secure cloud-based wallet solution for the marinate.io application.
  • Helped with the deployment of the application on a Kubernetes cloud using Helm automation scripts.
Technologies: Python, Solidity, Ethereum, Kubernetes, Helm, Docker, Distributed Ledgers, APIs

Software Developer

2019 - 2020
Circular Capital AG
  • Found and implemented the optimal solution for futures contracts, e.g., analyzed existing trading data streams to get volume and spread patterns and performed various simulations.
  • Profiled performance (VTune) and optimized the trading platform, achieving approximately a 30% gain.
  • Handled several migrations: from RHEL 7 to RHEL 8: C++17 introduction, boost1.53 to 1.68, and Python 2.7 to Python 3.6, among others.
Technologies: NumPy, Algorithmic Trading, Linux, Python, High-frequency Trading (HFT), C++, Qt 5, Quantitative Modeling, APIs

Blockchain Architect

2018 - 2019
SophiaTX
  • Designed protocols for a B2B collaboration blockchain platform.
  • Architected software for the platform, translating business requirements into technical features.
  • Recruited the technical team, establishing Agile processes and leading the team.
  • Participated actively in the development of the platform.
Technologies: Cryptography, Blockchain, C++, Distributed Ledgers, Team Leadership, Management, Jira, APIs

Blockchain Developer and Architect

2018 - 2018
Media Protocol
  • Designed and implemented the protocol and smart contracts for addressed content consumption.
  • Participated in the creation of the yellow paper and the white paper.
  • Developed the application server, interacting with the mobile application and blockchain.
Technologies: SQL, Blockchain, Scala, Solidity, Ethereum, Distributed Ledgers

Chief Architect

2015 - 2017
Decent
  • Performed initial research and co-created a novel cryptographic protocol for a decentralized digital content marketplace, including two original zero-knowledge proofs.
  • Led the delivery of the MVP, used as a base for successful fundraising.
  • Built and led a geographically distributed team of around 12 people and set agile development processes and tools.
  • Delivered the blockchain platform in extremely challenging time constraints.
Technologies: Cryptography, Blockchain, C++, Python, Java, Distributed Ledgers, Team Leadership, Management, Jira

Solution Architect

2007 - 2015
Ericsson
  • Created, designed, and led the implementation of a platform for mobile data charging and regulatory compliance.
  • Sold and delivered a PSTN-to-IMS migration project: one of the first migrations of this kind in the world.
  • Integrated a platform for resource admission and control into a telco environment as well as designing and implementing the changes required by the customer.
  • Led customer delivery projects as the technical SPoC responsible for delivery and acceptance documentation, negotiating interfaces, managing change requests, leading delivery teams (2-8 people), performing code reviews, and driving the acceptance.
Technologies: Session Initiation Protocol (SIP), Networks, SQL, Java, SIP, MySQL, Management

CS Engineer

2006 - 2007
LogicaCMG
  • Created set of Perl scripts for automated health check of a platform.
  • Solved several software and configuration issues at client installations.
  • Worked on deployment projects, prepared installation scripts, and traced issues.
Technologies: Session Initiation Protocol (SIP), Networks, SQL, Bash, SIP

Developer

2001 - 2006
Siemens
  • Worked on a SIP softswitch solution (IMS).
  • Implemented a scriptable SIP test tool.
  • Worked on mobile phone firmware (SIP stack and Push-to-talk application).
  • Created automated test scripts for the SIP softswitch platform.
  • Developed a test SIP application server.
Technologies: Session Initiation Protocol (SIP), Networks, SQL, Bash, Java, C++, C, SIP

IP Multimedia Subsystem

Developed the SIP softswitch platform, including test tools and test cases. Did testing and troubleshooting.

IMS Mobile Client

Implemented an IMS and push-to-talk client to a mobile phone firmware (Siemens 65 line and later).

Platform for Mobile Sharing and Regulatory Compliance

Designed and implemented a platform that collects usage data and performs checks for regulatory compliances, tariff conditions, and rates the subscriber usage.

IPTV Applications

Created applications for the IPTV platform during a pre-sale project.

Resource Admission and Control

Integrated a resource admission and control platform for a telecom network. Designed and implemented necessary changes to the platform.

DECENT Publishing Platform

Leading the research and development of a decentralized, blockchain-based digital content marketplace. Performed initial research, and co-created novel cryptographic protocol, including two zero-knowledge proofs. Implementing proofs of concept (C++, Python). Led the delivery of the MVP, used as a base for fundraising.

After successful fundraising, participated in the growth phase as lead architect/product owner. Built the geographically distributed team of around 12 people and set agile development processes and tools. Closely cooperated with management in defining and prioritizing features and delivering the back-end part of the solution in a very tight timeframe. Lead developer (contributing approx. 20kLOC) Successfully delivered the blockchain back end and APIs (C++11/14). SPoC for all technical matters.

SophiaTX

https://github.com/SophiaTX/SophiaTX
Responsible for the design and development of the DLT B2B solution. Built the team from scratch, established agile development processes and tools, and acted as technical product owner, creating the product in cooperation with business, prioritizing the product backlog, and managing releases in order to maximize the value delivered with the given resources. Led all development efforts, including API and SDK (JS/Java/.NET) design and supervising implementation, creation of various tools, and consultation with internal stakeholders and prospective customers.

Media Protocol

https://github.com/MediaProtocol/MediaProtocol
Contract role for a startup in the media and advertising area, aiming to introduce a new decentralized application for targeted content promotion. Provided advisory regarding feasibility and architecture of the DApp. Developed the DApp’s smart contract and back end.

High-frequency Derivates Trading Platform

Contributed to a high-frequency derivates trading platform. Extended the current functionality to trade contracts of the same product code with different delivery dates, improved the codebase to remove some existing technical debt, and performed extensive performance profiling and optimization, among other initiatives.

NFT Marketplace

https://marketplace.equinox.fund/
An NFT marketplace, operating both over ERC1155 and ERC721, with both custodian mode and A fully smart-contract-based back end. The implementation allows a high level of customization of the workflows and was implemented both as A customer project and as a base for digital asset exchange, an NFT-based IoT stream monetization platform.
The platform utilizes a unique decentralized identities document and verifiable credentials technology to store metadata.

Digital Asset Exchange

A platform integrated with a marketplace to monetize and process data streams, particularly IoT data.
It is built on top of an NFT marketplace, an IoT hub, and Kafka. As a unique feature, it allows the implementation of serverless data processing functions that can be bound to the data streams, process them, and provide results via API or send them back as a new stream to the DAE.
2009 - 2011

Master's Degree in Business Administration

City University of Seattle - Bratislava

2001 - 2005

Bachelor's Degree in Informatics

Masaryk University - Brno, Czech Republic

Libraries/APIs

HDF5, NumPy, React, Node.js

Tools

Provisioning Tools, Jira, CLion, GCC, Helm, IBM MQ, TIBCO Rendezvous, Azure IoT Hub, VTune

Languages

Python, C++, C, Solidity, Java, SQL, Bash Script, HTML, Bash, Scala, JavaScript, Python 3

Frameworks

Boost, Qt 5, Express.js, Next.js

Platforms

Blockchain, Linux, Ethereum, Kubernetes, Docker, Apache Kafka, Azure, Blockchain Platforms

Paradigms

Software Testing, Load Testing, Management, Serverless Architecture

Storage

MySQL, SQLite

Industry Expertise

High-frequency Trading (HFT)

Other

Architecture, Smart Contracts, LDAP, SIP, Networks, Integration, System Architecture, Session Initiation Protocol (SIP), Distributed Ledgers, Mathematics, Cryptography, Peer-to-peer Networking, Algorithmic Trading, Quantitative Modeling, Team Leadership, APIs, Clang, FIX Protocol, WebAssembly (Wasm), Business Administration, Non-fungible Tokens (NFT), Ethers.js, Decentralized Identity (DCI), Bitcoin, Ethereum Smart Contracts, Cryptocurrency

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