Clemens Helm, Software Developer in Vienna, Austria
Clemens Helm

Software Developer in Vienna, Austria

Member since September 29, 2017
Clemens has been working as a full-stack web developer for over a decade and a half. He's passionate about designing and building high-quality products. What he loves most about freelancing is the opportunity to encounter various types of projects, people, and cultures. Working this way, he constantly gains experience and knowledge for his next projects.
Clemens is now available for hire


  • ChillBill
    React, Ruby, Meteor
  • Clemens Helm
    PHP, Sass, jQuery, React, JavaScript, Meteor, Ruby on Rails (RoR), Ruby
  • Inselberg
    PostgreSQL, Ruby on Rails (RoR), Ruby



Vienna, Austria



Preferred Environment

Git, Zsh, ITerm, Vim Text Editor, Atom, MacOS

The most amazing...

...platform I've built is Codeship, a continuous integration service for developers.


  • CEO | CTO

    2015 - PRESENT
    • Created a web platform for automated accounting using Meteor, MongoDB, and React.
    • Developed a robust invoice recognition software using Ruby, ImageMagick, and Tesseract.
    • Led a team of nine brilliant developers.
    • Created a strong product vision and planned the product features according to the vision and customer feedback.
    • Used several APIs for reliable currency conversion, safe vat number validation, and others.
    Technologies: React, Ruby, Meteor
  • Freelance Web Application Developer

    2006 - PRESENT
    Clemens Helm
    • Developed solid corporate websites with PHP, JavaScript, and CSS.
    • Helped early-stage startups with their software architecture by developing an MVP and mentoring junior developers.
    • Created features for legacy Ruby on Rails codebases and cleaned them up by introducing test-driven development followed by an extensive refactoring.
    • Implemented data imports from Twitter, Instagram, and other APIs.
    • Processed images with ImageMagick to enhance certain aspects like their dominant color—in a way like Instagram filters.
    Technologies: PHP, Sass, jQuery, React, JavaScript, Meteor, Ruby on Rails (RoR), Ruby
  • IT Consultant | Mentor

    2015 - 2016
    • Advised a team of founders about technology stacks and product strategies.
    • Mentored junior developer on how to develop a solid Ruby on Rails app.
    • Implemented critical features which required a senior developer.
    • Reviewed code to ensure code quality and performance.
    • Provided my product team with feedback on their roadmap.
    Technologies: PostgreSQL, Ruby on Rails (RoR), Ruby
  • Full-Stack Developer

    2014 - 2015
    • Created a reliable business workflow web application for real-estate companies.
    • Refactored the existing code to make it as maintainable as possible.
    • Gained a lot of experience with MongoDB indexing and deployment on a database of a few terabytes.
    • Worked on a huge Ruby on Rails app with hundreds of thousands of lines of code.
    • Developed a sophisticated full-text search with Elasticsearch and gained experience in deploying it.
    Technologies: Redis, MongoDB, Ruby on Rails (RoR), Ruby
  • Vice President of Engineering

    2012 - 2014
    • Developed a hosted continuous integration platform using Ruby on Rails, PostgreSQL, and LXC.
    • Led a team of several brilliant software developers.
    • Participated in the TechStars Boston program.
    • Managed and developed the front- and back-end of the entire Codeship web application.
    • Developed an exhaustive testing suite to ensure the reliability and expandability of the platform.
    Technologies: Sass, LXC, Redis, PostgreSQL, Ruby on Rails (RoR), Ruby


  • Codeship (Development)

    Codeship is a continuous integration platform in the cloud. I was involved in developing the entire web application as well as the continuous integration service. I developed a highly scalable application which is used by thousands of software development teams every day.

  • ChillBill (Development)

    An automated accounting tool for small businesses. As the CEO and CTO, I was involved in the technical and production aspects as well the business side. Through this, I learned to view software applications from different angles.


  • Languages

    JavaScript, Ruby, SQL, CSS, Sass, HTML5, PHP, Swift
  • Tools

    Cucumber, Codeship, AWS ECS, Git, Atom, Vim Text Editor, Zsh, AWS ECR, AWS SDK, AWS IAM, ITerm
  • Paradigms

    Test-driven Development (TDD), Behavior-driven Development (BDD), Object-oriented Programming (OOP), Unit Testing, Testing, Software Testing, Continuous Delivery (CD), Continuous Development (CD), Functional Programming, Continuous Integration (CI), Scrum
  • Platforms

    Meteor, Heroku, Amazon Web Services (AWS), MacOS, AWS EC2, Docker
  • Other

    Semantic UI, Product Management, Tesseract, Usability, LXC, Image Processing, Lean Product Development, Product Development
  • Frameworks

    Ruby on Rails (RoR), Material-UI, Express.js, React Native
  • Libraries/APIs

    React, Node.js, jQuery, ImageMagick
  • Storage

    AWS S3, Redis, MongoDB, PostgreSQL, Databases, Memcached, JSON


  • Master's degree (in progress) in Software Engineering and Internet Computing
    2008 - 2017
    The Vienna University of Technology | TU Wien - Vienna, Austria
  • Master's degree (in progress) in Media and Computer Science
    2008 - 2017
    The Vienna University of Technology | TU Wien - Vienna, Austria
  • Master's degree (spent a semester abroad) in Computer Engineering
    2009 - 2009
    Faculdade de Engenharia da Universidade do Porto - Porto, Portugal
  • Bachelor's degree in Media and Computer Science
    2003 - 2008
    The Vienna University of Technology | TU Wien - Vienna, Austria

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