Jaak Vlasveld, Developer in Arnhem, Netherlands
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Jaak Vlasveld

Verified Expert  in Engineering

Bitcoin Developer

Arnhem, Netherlands

Toptal member since October 17, 2022

Bio

Jaak is a polyglot developer with infrastructure experience working on back-end systems and blockchain technology. He is formally educated in distributed systems engineering and has professional knowledge of developing core blockchain technology and crypto trading services. Jaak is well versed in C++, Go, Python, and other languages development and is used to working in Agile teams with cross-platform deployment, including with Docker, Kubernetes, and cloud environments, such as GCP and Proxmox.

Portfolio

Self-employed
Dart, Flutter, gRPC, Protobuf, AsyncAPI, Unit Testing, Functional Testing...
3RE
C++, Ragel, Standard Template Library (STL), Functional Requirements...
Green IT Amsterdam Region
Communication, Business Strategy, Innovation Management, IT Project Management...

Experience

  • C++ - 8 years
  • Linux - 7 years
  • Git - 6 years
  • Bitcoin - 5 years
  • User Acceptance Testing (UAT) - 5 years
  • Dash - 3 years
  • Bitcoin Cash - 3 years
  • Go - 2 years

Availability

Part-time

Preferred Environment

Linux, Visual Studio Code (VS Code), C++, Go, Bitcoin, Bitcoin Cash, Dash

The most amazing...

...blockchain feature I've delivered is a consensus-validated system for secondary tokens and NFTs.

Work Experience

Developer

2021 - PRESENT
Self-employed
  • Delivered the core technology for Oracle-based consensus-validated sports betting on the blockchain.
  • Developed Traidz's crypto trading engine to enable it to trade reliably at seven exchanges while having access to 21, and contributed to the open source trading engine GoCryptoTrader.
  • Managed stakeholder alignment for a medical data blockchain project in cooperation with Avisi.
Technologies: Dart, Flutter, gRPC, Protobuf, AsyncAPI, Unit Testing, Functional Testing, PostgreSQL, Linux, Docker, GitHub Actions, Git, Scrum, DevOps, C++, Python, Standard Template Library (STL), Functional Requirements, Regression Testing, Bitcoin, Bitcoin Cash, Dash, LevelDB, CircleCI, IT Project Management, Project Planning, Communication, Go, Blockchain

Blockchain Developer

2017 - 2021
3RE
  • Developed ATP, a consensus-validated secondary token based on Andrew Stone's group tokenization proposal for cryptocurrencies in the bitcoin family. Led the adoption of this token system with two POS coins.
  • Launched a Dash-based cryptocurrency with permission masternodes and the ATP token protocol for a gaming entertainment ecosystem.
  • Cultivated and maintained a consensus-validated sports betting chain, acting as developer, architect, team lead, and lead developer.
  • Developed and contributed to the launch of two other cryptocurrencies.
  • Specified an exchange API and contributed to the development of the exchange providing the API.
  • Built and delivered a blockchain education program and training workshops to the Amsterdam University of Applied Sciences, the Utrecht University, and the Windesheim University of Applied Sciences.
Technologies: C++, Ragel, Standard Template Library (STL), Functional Requirements, Unit Testing, Functional Testing, Regression Testing, Bitcoin, Bitcoin Cash, Dash, Linux, CircleCI, Git, DevOps, Kanban, CI/CD Pipelines, JavaScript, Travis CI, LevelDB, Agile, TypeScript, OpenAPI, AsyncAPI, React, Docker, Offshore Team Management, Redis, MongoDB, IT Project Management, Blockchain

Director

2012 - 2019
Green IT Amsterdam Region
  • Established, managed, oversaw, and contributed to seven projects with over one million euros in budgets.
  • Ensured the commitment of 70% of Amsterdam's data centers to sustainability goals.
  • Managed piloting activities for integrating data centers as demand-response actors in smart energy grids.
  • Led the communication and validation activities for developing the EU roadmap for sustainable smart neighborhoods.
  • Provided expert input on strategies for sustainable software development.
  • Led the knowledge-sharing activities for developing a certified learning program on energy-efficient data centers.
Technologies: Communication, Business Strategy, Innovation Management, IT Project Management, Project Budget Management, Business Requirements, Roadmaps, User Acceptance Testing (UAT)

Consultant

2008 - 2012
Self-employed
  • Evaluated the funding structure of national ICT infrastructures for research in the Netherlands.
  • Contributed to initiating structural innovation activities on sustainable ICT in the Netherlands.
  • Evaluated telecare systems and advised how to use video communication between health care providers and their clients, segmented per type of care.
Technologies: Communication, Roadmaps, User Acceptance Testing (UAT)

Experience

Atomic Token Protocol for Bitcoin-based Coins

A secondary token protocol for blockchains in the bitcoin family. Bitcoin cash' Andrew Stone specified the group tokenization protocol and delivered a POC implementation. I turned the POC into a fully working token system and launched it on two POS blockchains. ATP has very little overhead in data, memory, and CPU consumption. The validation at the consensus level makes it robust and secure. And while the token system can be used as a fully permissionless system, I adapted it to enable permission tokens, which were used as activation tokens for a permission masternode network. In addition to regular tokens, the system offers semi-fungible and non-fungible tokens (NFTs).

Blockchain-based Sports Betting

A first-layer blockchain fully dedicated to sports betting, where the network functions as the house. The system is currently widely used by sports bettors and bookies who want to hedge their own risks. As the lead blockchain developer and on-chain application architect, I ensured the chain had a secure consensus system, translated the application requirements into a consensus-level gaming protocol, and oversaw the implementation of the gaming protocol by several offshore teams. I also supervised and contributed to network upgrades and ensured the flawless quality of work.

Robotraidr

An automated cryptocurrency trading platform based on the open source package GoCryptoTrader, a basic platform to connect to exchanges, place trades, and monitor exchange data.

I extended this platform to connect to new exchanges, automatically trade with a custom trading strategy (such as grid trading, arbitrage, accumulation, and distribution), generate reports and insights, and monitor trading activity on a cross-platform app.

Education

2001 - 2009

Master's Degree in Philosophy of Science, Technology and Society

The University of Twente - Enschede, Netherlands

2000 - 2008

Master's Degree in Telematics

The University of Twente - Enschede, Netherlands

Skills

Libraries/APIs

Protobuf, Standard Template Library (STL), OpenAPI, React

Tools

Git, CircleCI, Ragel, Travis CI, GitLab CI/CD, GitHub

Languages

C++, Go, Python, UML, JavaScript, Java, Dart, TypeScript

Platforms

Linux, Blockchain, Visual Studio Code (VS Code), Bitcoin Cash, Docker

Paradigms

User Acceptance Testing (UAT), Kanban, Unit Testing, Functional Testing, Scrum, DevOps, Agile

Storage

LevelDB, PostgreSQL, Redis, MongoDB

Industry Expertise

Marketing

Frameworks

Flutter, gRPC

Other

Bitcoin, Dash, Roadmaps, Functional Requirements, Communication Strategy, Communication, Innovation Management, Business Requirements, AsyncAPI, GitHub Actions, Regression Testing, IT Project Management, Project Planning, CI/CD Pipelines, Offshore Team Management, Business Strategy, Project Budget Management

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