James Freiwirth, SOLID Principles Developer in London, United Kingdom
James Freiwirth

SOLID Principles Developer in London, United Kingdom

Member since July 18, 2015
James has over 14 years experience building software in industry. He is a great problem-solver and can apply himself to many different domains. He can gather requirements and design, build, and test complete systems from beginning to end whilst communicating effectively with the business. He believes in using the latest tools and techniques to perfect his craft whilst never losing sight of the goal: delivering business value for the client.
James is now available for hire




London, United Kingdom



Preferred Environment

Scala, Git, Xamarin, C#, F#, Visual Studio

The most amazing...

...thing I've built was an extremely high-performance trading grid using a combination of functional programming and a hardware-accelerated game engine.


  • Senior Software Consultant

    2018 - 2019
    Adaptive FInancial Consulting
    • Contributed to the construction of a low-latency crypto exchange.
    • Gathered requirements, architected, and developed for FIX Gateway.
    • Worked on tools for cross compilation allowing targeting of multiple platforms/languages.
    Technologies: C#, TypeScript, Kotlin, Java
  • Senior Software Consultant

    2017 - 2018
    • Worked on a high-volume API powering a global eCommerce brand.
    • Introduced software to reduce bureaucracy and allow faster deployments, saving both time and money.
    Technologies: Azure, ASP.NET, F#, C#
  • Senior Software Consultant

    2015 - 2016
    • Developed an electronic trading platform for commodities traditionally traded by email/phone.
    • Introduced functional programming techniques to rapidly build new applications with fewer defects.
    • Worked on an innovative moment-marketing tool.
    • Implemented CI/CD pipelines for rapid cloud deployment.
    • Implemented an event-sourced architecture to provide flexibility and allow full audit history.
    Technologies: F#, C#, .NET
  • Vice President, Quantitative Strategies

    2014 - 2015
    Credit Suisse
    • Worked on the front-office building pricing application for financial derivatives.
    • Worked with a distributed team in London, New York, and Wroclaw, Poland.
    • Worked with stakeholders to gather business requirements and translated to production quality code.
    Technologies: C#, F#
  • Software Consultant

    2013 - 2014
    Perfect Shuffle, Ltd.
    • Designed and developed a cloud-hosted, responsive SaaS application for delivering virtual gift cards to small retailers.
    • Designed and developed a high-performance trading grid control for financial services using F# and XNA.
    Technologies: ZURB Foundation, XNA, Compass, Sass, HTML5, C#, F#
  • Software Consultant

    2011 - 2013
    Trayport Contigo
    • Worked in a mid-sized Agile team to develop Joule, a new commodity trading platform for the energy market.
    • Used TDD and BDD within the Agile setting to reduce regressions and involve stakeholders in writing requirements.
    • Used functional programming in a commercial environment.
    Technologies: C#, F#
  • Software Consultant

    2011 - 2011
    • Reverse-engineered a legacy application to gather requirements.
    • Designed and built a web application using ASP.NET MVC and C#.
    • Migrated existing application data to the new platform.
    Technologies: C#, .NET
  • Software Consultant

    2010 - 2011
    ED&F Man
    • Built a web application to allow business owners to track and audit counterparty risk.
    • Integrated with external accounting systems.
    • Designed and built a custom blotter for importing data from Excel.
    Technologies: ASP.NET MVC, MSMQ, C#
  • Software Engineer

    2009 - 2010
    Condé Nast Publications
    • Worked on the back end for high-volume and high-profile websites including Vogue, Glamour, Wired, and CN Traveller.
    • Built a custom asynchronous analytics platform.
    • Customized the CMS to integrate fast text searching using Lucene.
    Technologies: jQuery, ASP.NET MVC, Apache Lucene, Umbraco, CSS, HTML, C#



  • Languages

    C#, F#, JavaScript, SQL, CoffeeScript, HTML, Java, Kotlin, TypeScript, HTML5, Sass, Assembler x86, C++, C, Haskell, Scala, CSS
  • Frameworks

    .NET, Business Rules Engine, .NET Core, ASP.NET MVC, ServiceStack, Compass, ZURB Foundation, ASP.NET
  • Paradigms

    DevOps, Functional Programming, Test-driven Development (TDD), REST, Functional Reactive Programming, Object-oriented Programming (OOP), Agile Software Development, Behavior-driven Development (BDD)
  • Platforms

    Azure, Docker, Linux, Xamarin, Umbraco
  • Other

    SOLID Principles, SaaS, OWIN, MSMQ
  • Libraries/APIs

    jQuery, XNA, Apache Lucene
  • Storage

    Microsoft SQL Server, PostgreSQL, MySQL, NoSQL
  • Tools

    Visual Studio, Git


  • M.Sc. Degree in Computer Science
    2006 - 2007
    University of Newcastle-upon-Tyne - UK
  • B.Sc. Degree in Mathematics
    2003 - 2006
    University of Bath - UK

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