Holger Schmitz, Software Developer in Newbury, United Kingdom
Holger Schmitz

Software Developer in Newbury, United Kingdom

Member since May 15, 2018
Holger has over two decades of experience in developing and implementing large-scale codebases. He is proficient in JavaScript, PHP, C++, Java, and PHP. He has worked in teams of varying sizes, and he enjoys taking on new challenges. Holger believes that the keys to success when working remotely with a client is good communication and clear project goals.
Holger is now available for hire




Newbury, United Kingdom



Preferred Environment

Linux, Atom.io, Eclipse, IntelliJ, PhpStorm, Git

The most amazing...

...thing I've developed was Schnek, a C++ library for simulations on large-scale clusters.


  • Technical Writer

    2018 - PRESENT
    Okta, Inc.
    • Developed various Angular applications.
    • Implemented single sign-on authentication.
    • Wrote a number of tutorials.
    Technologies: Angular, REST API, OAuth 2, JWT
  • Lead Developer

    2011 - PRESENT
    Cogito Learning, Ltd.
    • Designed and implemented REST APIs for web and mobile applications.
    • Designed and developed an Android app for GCSE maths training.
    • Created an Android app for calculating and explaining mathematical derivatives.
    • Built a library for parsing and manipulating mathematical expressions.
    • Implemented a WordPress tracking system for recording links to external resources.
    • Extended a shopping cart system to allow highly customized products.
    • Constructed an Android app for calculating and explaining mathematical derivatives.
    • Implemented a WordPress theme framework for responsive single-page websites.
    • Created a React-based extension for the WordPress dashboard.
    • Implemented various websites from mockups.
    • Designed and implemented a financial risk analysis software.
    • Created a database abstraction layer in C++ to work with different SQL databases.
    • Led the software development team.
    • Created single-page applications using Angular.
    Technologies: JavaScript, Node.js, React, Angular, PHP, Java, HTML, CSS, C++
  • Full-stack JavaScript/Angular Engineer

    2019 - 2020
    Pampered Chef
    • Implementing the front-end experience in Angular from mockups.
    • Created back-end endpoints using Node.js/Express.js.
    • Composed unit tests with 100% code coverage.
    • Participated in regular standups and sprint meetings.
    • Participated in code reviews.
    Technologies: JavaScript, TypeScript, Angular, Node.js, Express.js, Jenkins
  • Lead JavaScript Developer

    2018 - 2020
    Push Technology, Ltd.
    • Maintained a JavaScript client system that communicates with a server through WebSockets.
    • Implemented new features in the JavaScript part of the product.
    • Converted the JavaScript code base to TypeScript.
    • Fixed bugs in the code as they appeared.
    • Updated the build process using Maven and Gulp.js.
    Technologies: JavaScript, TypeScript, Node.js, React, WebSockets, Jenkins, Maven, Gulp
  • Theoretical Physicist

    2013 - 2018
    STFC, Rutherford Appleton Laboratory
    • Implemented numerical algorithms in C++, Python, and MATLAB.
    • Created large-scale simulation codes using MPI.
    • Supported large-scale simulation packages.
    • Designed and implemented a library for grid-based simulations on large clusters.
    • Built tools for working with large datasets.
    • Implemented a reader and converter for proprietary data format.
    • Integrated systems of differential equations using various methods.
    • Implemented automatic symbolic manipulation of mathematical systems using Mathematica.
    • Created a web-based automatic formula book based on React.
    • Developed a parser for a C-style declarative language.
    Technologies: C++, JavaScript, Python, MATLAB, Mathematica


  • Diffusion JavaScript Client (Development)

    As the senior JavaScript engineer for Push Technology (Pushtechnology.com), I was responsible for porting their Diffusion client from JavaScript to TypeScript, as well as implementing new features and fixing bugs.

    The Diffusion Intelligent Data Platform™ synchronizes, manages, and distributes data among applications, devices, and systems via the web, mobile, and satellite networks.

  • Frmlae (Development)

    This is an online formula book.

    • Front end: A single-page application using Angular 7, RxJS, Material Design.
    • Back end: A REST API using Node.js, Express.js, and MongoDB.
    • Deployment: Used Digital Ocean Ubuntu 18.04 Droplet.

  • Tutor Scout (Development)

    Here, I worked as the lead product developer of a platform that matches students with tutors.

    • Analyzed the requirements.
    • Chose the technology stack.
    • Implemented the front-end and back-end.

    Technologies: PHP, MySQL, Apache, Prado PHP Framework

  • Schnek (Development)

    Schnek is a C++ library for developing parallel simulations on Cartesian grids.

    • Set up a file reader with C-style syntax.
    • Implemented extendable formulas in the setup files.
    • Constructed a hierarchical structure of simulation components.
    • Possesses multi-dimensional grids.
    • Initialized the grid from formulas in a setup file.
    • Contains boundary cells and ghost cells.
    • Provides MPI support for parallelization.
    • Installed an MPI update of ghost cells to neighboring processes.
    • Contains easy-to-use parallel and serial HDF5 output of grids.
    • Developed a literature reference system to encourage collaborative development of large codes.

  • Financial Risk Analysis (Development)

    I designed and implemented a complete risk analysis framework. It has cash flow generation, pricing, and stress testing of financial products using C++ and QuantLib.

  • Angular 7 and Node.js/Express.js Tutorial (Other amazing things)

    This tutorial guides the reader through the steps to produce a single-page CRUD application. It focuses on authentication, both in the front-end and back-end, using Okta single sign-on.

    • Front-end: Used an Angular 7.0.2 release.
    • Back-end: Built with Node.js, Express.js, and TypeScript.

  • Moreland Accountancy (Development)

    ROLE: Lead WordPress Developer

    I was responsible for the development of a plugin that allows content editors to assemble pages based on pre-designed blocks. The plugin hooks into the edit-post page and displays a React-based user interface with drag-and-drop functionality. I also implemented the design based on templates.

  • Pampered Chef (Development)

    Pampered Chef is a marketing company selling food products and kitchen utensils. I was a full-stack developer working in a team and responsible for extending the functionality and resolving issues. The technology stack was based on Node, Express, and Angular 7.

    The workflow was based on Agile principles with daily standup and biweekly sprints.


  • Languages

    TypeScript, PHP, C++, JavaScript, Sass, HTML, Bash, SQL, CSS, HTML5, Python, Java, GraphQL
  • Frameworks

    ZURB Foundation, Angular, Express.js, Boost, Bootstrap, Sails.js, JSON Web Tokens (JWT), Jasmine, Jest
  • Libraries/APIs

    Node.js, React, MPI, Vue.js 2, Stripe API, RxJS
  • Tools

    MATLAB, Gulp.js, Maven, NPM, Jenkins, CircleCI, Karma
  • Platforms

    Software Design Patterns, WordPress, Linux
  • Other

    WordPress Plugins, Cluster Computing, WebSockets, Statistics, Quantitative Finance, WordPress Themes
  • Storage

    MySQL, MongoDB


  • PhD degree in Theoretical Physics
    1995 - 2000
    Ruhr University Bochum - Bochum, Germany
  • Diploma (Master's) degree in Physics, Computer Science
    1989 - 1995
    Ruhr University Bochum - Bochum, Germany

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