Sebastian Klier Founder at NewWorldFans, NewWorld-Map. Full-Stack Developer with Kubernetes Experience.

Sebastian Klier - Experienced Full-Stack and DApp Developer

I build complex things for the web with Rails, Golang, Vue, React, Node.js or PHP. I also work on Blockchain projects (Golang Smart Contracts, Solidity & Ethereum Smart Contracts). - LinkedIn - GitHub


Languages: JavaScript, Golang, Ruby, PHP, Python, Solidity

Frameworks: React, Vue, Angular, Symfony, Ruby on Rails, Django, Truffle

Experience with: Node.js, Express.js, MySQL, PostgreSQL, Redis, MongoDB, Memcache, Solr, RabbitMQ, REST, WebSockets, AWS, Google Cloud, Docker, Ansible, Kubernetes, Ethereum, Smart Contract Development and various other buzzwords


easybill GmbH Remote
Ruby Developer March 2019 - Present

  • Working on a Ruby on Rails invoicing system integrating with 3rd-party APIs for Amazon, Shopify, Ebay and other e-commerce systems.

Loom Network Remote
Senior Developer March 2018 - March 2019

  • Smart Contract development with our Golang SDK
  • Worked on a social network, smart contracts for our Zombie Battleground game, as well a marketplace
  • Developed features in Ruby on Rails
  • Frontend development with Vue.js
  • Kubernetes deployments
  • Production troubleshooting
  • Code Reviews

The NetCircle Shanghai, China
Advanced Full-Stack Developer September 2014 – March 2018

  • Working on a large social network site with 250,000 active members logging in every week, nearly a million page views and more than 100,000 messages sent between users each day.
  • Worked with React/Redux, Node.js/Epxress.js on a single-page application.
  • Wrote data migration scripts and prototyped backend services using Golang.
  • Worked with MySQL, MongoDB, Redis, Memcache, RabbitMQ, Solr, ElasticSearch, a payment service, an ad platform and an image cluster.
  • Implemented testing and deployment strategies.
  • Responsible for training and mentoring of junior developers, conducting code reviews, interviewing potential hires.
  • Held presentations and technical talks about topics such as Golang, Blockchain, Doctrine internals, best practices.

FrontCoding Shanghai, China
Senior Developer April 2014 – September 2014

  • Training and mentoring junior developers, taking part in interviews, conducting code reviews.
  • Worked on multiple projects using Angular.js, Sencha ExtJS, Symfony.

Oelder WerbeWerk Oelde, Germany
Web Developer Juli 2005 – April 2014

  • Started as a part-time job during school and evolved into a full-time remote position.
  • Server administration, shell scripts, developing internal tools (PHP, Python, Bash).
  • Developed applications for customers based on Ruby on Rails, PHP, Python and various CMS or eCommerce solutions.

Jobware Online Service GmbH Paderborn, Germany
Software QA Engineer (part-time) October 2008 – March 2010

  • Main responsibilities included creating, reviewing and conducting test cases and working on the software documentation.


  • Contributed/contributing to open-source projects in the Ethereum space (Colony, Status-Go) and others (GitLab,
  • Working on a site to monitor Decentraland parcel auctions.
  • Working on a browser game based on Rails/Vue.js.
  • Briefly worked on online courses for Vue.js:
  • Led small teams of volunteer editors and designers at different website projects and took care of search engine optimization, community and social media management, as well as development of custom tools.