Holger Schmitz
Verified Expert in Engineering
Full-stack Developer
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 are good communication and clear project goals.
Portfolio
Experience
Availability
Preferred Environment
Git, Linux, Visual Studio Code (VS Code), TypeScript, C++, MacOS
The most amazing...
...thing I've developed was Schnek, a C++ library for simulations on large-scale clusters.
Work Experience
Senior Software Engineer
Reddit, Inc.
- Implemented new landing experiences that provide cross-promotion between the website and the mobile app. The goal of this project was to improve the user experience of existing popups while maintaining conversion.
- Created the events from the front-end and server-side rendered content that allowed the data team to perform A/B testing.
- Tracked progress of tasks and bugs using Jira and Confluence.
Node.js/Full-stack Developer
Usable Machines, Inc.
- Implemented a REST API for enterprise customers based on Express and tRPC.
- Integrated the back end with AI services like OpenAI GPT, Google BERT, Microsoft Tapex, etc.
- Improved existing code quality by adding unit tests and enforcing coverage.
- Planned quality and performance metrics from a product owner viewpoint.
- Implemented front-end components using React and Next.js. Made visual design decisions.
Full-stack Developer
Pampered Chef - E-Commerce
- Developed a new shopping experience using microservices based on a complex business structure.
- Took responsibility for designated packages and services. and decided on architecture guidelines and code quality standards.
- Deployed and launched the new shopping experience and provided technical support.
- Fixed bugs that had an impact on the business with fast turnaround times.
- Managed ongoing work and bugs using Jira and agile processes.
Technical Writer
Okta, Inc.
- Developed various applications using Angular, React, NextJS, and other technologies.
- Implemented single sign-on authentication using the Okta libraries.
- Documented the source code and wrote numerous tutorials.
Lead Developer
Cogito Learning, Ltd.
- Designed and implemented financial risk analysis software for www.epsilon-risk.com.
- Designed and implemented REST APIs for web and mobile applications.
- Designed and developed an Android app for GCSE maths training.
- Built a library for parsing and manipulating mathematical expressions and created an Android app for calculating and explaining mathematical derivatives.
- 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 and created a React-based extension for the WordPress dashboard.
- Implemented various websites from mockups in Figma.
- Created a database abstraction layer in C++ to work with different SQL databases.
Full-stack WordPress Developer
Clorox
- Worked on multiple sites across the Clorox brand to provide updates to the CMS and implement changes in the front end. Sites include Glad.com, Hiddenvalley.com, Kingsford.com, and others.
- Performed accessibility audit of all sites of the Clorox brand.
- Converted smaller sites to static site generators Eleventy and Next.js. Sites include Hiddenvalleyranch.ca, Liquidplumr.com.au, Chux.com.au, and others.
Full-stack JavaScript/Angular Engineer
Pampered Chef
- Implemented 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 stand-up and sprint meetings.
- Participated in code reviews.
Lead JavaScript Developer
Push Technology, Ltd (now Diffusion Data)
- Maintained a JavaScript client system that communicates with a server through WebSockets.
- Implemented new features in the JavaScript part of the product.
- Converted the existing JavaScript codebase to TypeScript.
- Fixed bugs in the code as they appeared in a timely manner.
- Updated the build process using Maven and Gulp.js.
Theoretical Physicist
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.
Experience
Pampered Chef
https://www.pamperedchef.com/The workflow was based on Agile principles with daily standup and biweekly sprints.
Diffusion JavaScript Client
https://www.npmjs.com/package/diffusionThe Diffusion Intelligent Data Platform™ synchronizes, manages, and distributes data among applications, devices, and systems via the web, mobile, and satellite networks.
Frmlae
PROJECT SPECIFICS
• Front end: A single-page application using Angular 7, RxJS, and Material Design.
• Back end: A REST API using Node.js, Express.js, and MongoDB.
• Deployment: Used Digital Ocean Ubuntu 18.04 Droplet.
React Solitaire Demo
https://celebrated-daifuku-af55d3.netlify.app/Tutor Scout
http://tutorscout.co.ukSchnek
https://github.com/holgerschmitz/SchnekFEATURES
• Set up a file reader with C-style syntax.
• Implemented extendable formulas in the setup files.
• Constructed a hierarchical structure of simulation components.
• Possesses multidimensional 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 the collaborative development of large codes.
Financial Risk Analysis
https://www.epsilon-risk.com/Angular 7 and Node.js/Express.js Tutorial
https://developer.okta.com/blog/2018/10/30/basic-crud-angular-and-nodePROJECT SPECIFICS
• Front end: Used an Angular 7.0.2 release.
• Back end: Built with Node.js, Express.js, and TypeScript.
Moreland Accountancy
Lead WordPress developer
TASKS ACCOMPLISHED
I developed 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.
Skills
Languages
TypeScript, Sass, PHP, C++, JavaScript, CSS, HTML5, JavaScript 6, CSS3, Java, HTML, Bash, SQL, Python, GraphQL, ECMAScript (ES6)
Frameworks
ZURB Foundation, Angular, Next.js, Express.js, Boost, Bootstrap, Tailwind CSS, OAuth 2, Twig, Sails.js, JSON Web Tokens (JWT), Jasmine, Jest, Material UI, PRADO, Swagger
Libraries/APIs
Node.js, React, MPI, REST APIs, Elevate API, jQuery, Vue 2, Stripe API, RxJS, HDF5, Chai, Sinon.JS, Vue, Polymer, Lit
Tools
MATLAB, GitHub, Figma, Prisma, Atom, IntelliJ IDEA, PhpStorm, Git, Mathematica, Gulp, Apache Maven, NPM, Jenkins, CircleCI, Karma, MQTT, Apache, Mocha, SAP Hybris
Paradigms
MEAN Stack, Unit Testing, Microservices, High-performance Computing, REST
Platforms
Software Design Patterns, WordPress, Linux, Eclipse, Visual Studio Code (VS Code), Amazon Web Services (AWS), Firebase, NVIDIA CUDA, Oracle, AWS Lambda, Apache Kafka, MacOS, Docker
Other
WordPress Plugins, Full-stack, Front-end, APIs, Back-end, MERN Stack, Mathematics, Software Architecture, Data Structures, Full-stack Development, Cluster Computing, Architecture, Software Design, Quantitative Modeling, WebSockets, Statistics, Quantitative Finance, WordPress Themes, Mobile App Development, TCP/IP, Numerical Methods, Parsers, Okta, ECS, Drag & Drop, SVG, Algorithms, Data Compression, RPC, Artificial Intelligence (AI), LangChain, Pinecone, OpenAI GPT-3 API, Front-end Development
Storage
MySQL, PostgreSQL, MongoDB, Oracle SQL
Education
PhD in Theoretical Physics
Ruhr University Bochum - Bochum, Germany
Diploma (Master's) Degree in Physics and Computer Science
Ruhr University Bochum - Bochum, Germany
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