Frédérique Mittelstaedt
Verified Expert in Engineering
Software Developer
London, United Kingdom
Toptal member since February 22, 2019
Frédérique is a software engineer and entrepreneur with an MSc in theoretical physics from Imperial College London. He excels at building full-stack systems with the web, desktop, and mobile apps, microservices, and external integrations. Frédérique co-founded an international marketing agency and three startups in developer tools, cybersecurity, and AI. Frédérique regularly releases TypeScript packages and contributes to other open-source projects.
Portfolio
Experience
- JavaScript - 9 years
- Adobe Illustrator - 7 years
- Python 3 - 7 years
- Express.js - 4 years
- Docker - 4 years
- Node.js - 4 years
- React - 4 years
- TypeScript - 3 years
Availability
Preferred Environment
Git, Visual Studio Code (VS Code), i3, Arch Linux, MacOS
The most amazing...
...system I've built can identify arbitrage trading opportunities between any pair of cryptocurrencies on 94 exchanges in real time (updated every few seconds).
Work Experience
Engineering Manager, Messaging Foundations
- Established the messaging foundations team, its mission, charter, and technical and product roadmap.
- Led the design and development of Reddit's centralized streaming platform based on Apache Kafka, Apache Flink, and Flink Stateful Functions.
- Worked with cross-functional teams to support their adoption of the streaming platform.
Engineering Manager, Real-time Safety Applications
- Established the real-time safety applications team, its mission, charter, and technical and product roadmap.
- Grew my team to four back- and front-end engineers.
- Led the development of a stream processing platform based on Apache Kafka, Apache Flink, and Flink Stateful Functions.
- Built a framework and tooling for developing streaming applications running on Kubernetes in Python.
- Supervised the development of real-time safety applications.
- Worked with cross-functional teams to support their adoption of the streaming platform.
- Supervised the migration of a legacy real-time safety system to the new streaming platform.
Senior Software Engineer II
- Implemented features for the main site and internal applications using TypeScript, React, Redux, Python, and SQLAlchemy.
- Improved and upgraded the development tooling and workflow for several projects using TypeScript and Python.
- Coordinated the scrum process and helped improve communication within and between teams as scrum master for two teams.
Freelance Software Engineer
The Boston Consulting Group (BCG)
- Modified a web app to make it compatible with Internet Explorer 10+ and Microsoft Edge.
- Added and configured Babel and necessary polyfills for a web app built using Create React App to make it work on IE and Edge using the customize-cra library.
- Identified layout and performance issues using the browser profiling and implemented fixes to improve performance on IE and Edge.
Freelance Software Engineer
- Implemented features for the main site and internal applications using TypeScript, React, Redux, Python and SQLAlchemy.
- Improved and upgraded the development tooling and workflow for several projects (TypeScript & Python).
- Coordinated the scrum process and helped improve communication within and between teams as scrum master for two teams.
- Transitioned to a full-time position as a senior software engineer in May 2020.
Freelance Software Engineer
Wavve.co
- Refactored the Wavve.link app offering a shareable podcast web page with general info, links and the latest episode extracted from an RSS feed (built using Nuxt.js, Vuex, and Vue.js in JavaScript).
- Added an episode-list page to Wavve.link with an expandable collection of all episodes of a podcast and an HTML 5 audio player that sticks to the bottom of the screen to play each episode (including a popover to set the playback speed).
Freelance Software Engineer
ExxonMobil
- Developed a translator web app for ExxonMobil's global intranet using TypeScript, React, MobX with C# Azure functions; the back end was deployed on Microsoft Azure.
- Led weekly catch-up meetings with ExxonMobil teams in the US and Malaysia and provided technical guidance for project architecture and feature implementation.
- Rewrote an initial application prototype from JavaScript to TypeScript and configured all of the build tools.
- Implemented a React component library for ExxonMobil's design system, Unity.
- Implemented a multiresolution React icon library (including tests) using code generation based on SVG source files.
- Integrated the Microsoft Azure and Google Cloud private endpoint translation APIs with the web app for text translation.
- Created a responsive application UI using React and the component libraries I created with support for switching between Microsoft Azure and Google Cloud APIs.
- Integrated text-to-speech functionality using the Howler web audio library and the Azure Cognitive Services and Google Cloud text-to-speech APIs.
- Implemented an Azure functions endpoint for translating Word documents, Excel spreadsheets, PowerPoint presentations and plain text documents in C# using the Office OpenXml library and the Azure and Google Cloud translation APIs.
- Integrated authentication and access control using Azure Active Directory.
- Implemented proxy endpoints for all API calls for authentication and performance monitoring using C# Azure functions.
- Added support for Unicode input using an on-screen software keyboard.
- Cleaned up and documented the codebase and documented the application architecture for future maintainers.
Contract Software Engineer
Octeract
- Designed and built an IDE for creating and editing optimization problems/projects specified in the company's proprietary programming language.
- Extended the Monaco editor powering Visual Studio Code with a custom theme, language definition, and syntax completion handlers.
- Defined and implemented a custom project document file format.
Contract Software Engineer
AlliedCrowds
- Built a crowdfunding web app for the Islamic Development Bank (Isdb-innovate.org).
- Refactored the Vue.js codebase and integrated the Vuex state management library.
- Internationalized the back end and front end (supporting English, French, Arabic, Turkish, Bengali, Malay, Kazakh, and Indonesian).
- Designed the build system for six country-specific microsites (each localized with different design, text, and media).
- Helped launch the platform within 21 days of joining the team.
- Built a second web app with information material for entrepreneurs in Kenya and Nigeria with country-, sector- and company stage-specific information pathways within seven days.
Contract Software Engineer
Private Client
- Developed a blockchain explorer and cryptocurrency accounting system for Bitcoin and Ethereum.
- Implemented a method for efficiently tracking the flow of funds between different addresses.
- Deployed the system on DigitalOcean using Docker.
Contract Software Engineer
Private Client
- Built a system for the real-time detection of arbitrage opportunities between cryptocurrency pairs on 94 exchanges.
- Designed the algorithm to calculate the relative and total profit opportunities from the spread, order books, the exchange, and transfer fees.
- Created an efficient long/short hedging strategy to minimize fees and maximize processing speed.
- Implemented a LINE messenger bot to send out notifications when opportunities are detected.
- Deployed the system on AWS in an ECS cluster provisioned with Terraform.
Founder and CEO
Automorph
- Designed a programming and data language called Morph.
- Implemented the initial runtime and interpreter for Morph in Python.
- Installed a compiler for Morph using the LLVM compiler toolchain.
- Developed a web-based runtime for Morph using TypeScript.
- Designed and implemented the service- and component-oriented application framework Service.js in TypeScript.
- Designed and implemented the React UI component library Service UI using TypeScript, React, and the CSS-in-JS library emotion.
- Designed and implemented an extensible language- and framework-independent code generation library.
- Designed an AI system for the auto-generation of source code for multi-application software systems from requirements.
- Participated in the Zeroth.AI startup accelerator in Hong Kong in 2017.
Co-founder | CEO
Global Graduate Marketing
- Co-founded a digital marketing agency specializing in international graduate student recruitment with $500,000 annual revenue.
- Executed short-term marketing boosts to increase applicant numbers for specific programs.
- Implemented long-term marketing strategies, increasing applicant numbers by up to 2x-3x over three years.
- Built a large and international network of online and offline advertising partners (e.g., journals, conferences, and PhD and Master search portals).
Co-founder and CEO
Ruuta
- Implemented a user-friendly web-based UI for Ruuta's WiFi router operating system based on OpenWrt.
- Developed partnerships with router manufacturers.
- Took part in the first cohort of the CyLon cybersecurity accelerator.
- Presented Ruuta at RISEConf in Hong Kong in August 2015.
Contract Software Engineer
AlliedCrowds
- Refactored the codebase and added features to a crowdfunding platform web app.
Founder
Kozo
- Built a template-based system for software development and deployment.
Student Assistant (Software Engineer)
BTC | Business Technology Consulting AG
- Developed an inventory system using Java, Spring, and MySQL.
Freelance Web Developer
smart insights GmbH
- Developed the web version of the company’s tool for marketing research, "my opinion" with the functionality and design based on existing mobile apps.
- Created a survey engine supporting different types of questions and views.
- Integrated the UI with the company's pre-existing JSON API.
Various Student Assistant Positions
Jacobs University Bremen
- Organized events, handled technical repairs and installations, and administered to the Joomla website of the Alfried-Krupp-College (residential hall) as part of the college office team from Oct 2011 to Dec 2012.
- Supervised the public usage hours of the computer lab of the CLAMV laboratory (Computational Laboratory for Analysis, Modeling, and Visualization) from Sep 2011 to Dec 2013.
- Created the design, added content, and deployed the WordPress website of the Research Center Humanities, Modernity, and Globalization (HMG) prior to its opening conference in Jun 2011.
- Developed an online event planning system in PHP that is synchronized with an exchange calendar and integrates user login with an LDAP directory in Aug 2012.
- Developed the news carousel on the front page of the main university website and the slide show of the graduation 2013 microsite using jQuery from May 2013 to Jun 2013.
- Built a mobile-ready web app providing updated meal plans and collecting meal reviews for the university catering services in Aug 2013.
- Set up the computer lab and software for a workshop of the Basin and Petroleum System Dynamics Executive MSc program in Aug 2013.
- Created a graphical visualization tool for complex polynomials using Newton’s method for Mac OS X using Objective-C and Cocoa from Oct 2013 to Jan 2014.
- Developed a web application and data mining back-end for the analysis of search results from Google Search and Google Scholar and the semantic analysis of the search results from Nov 2013 to Jan 2014.
Freelance Typesetter
Prof. Birgit Mersmann
- Handled the typesetting of the client's postdoctoral thesis “Schriftikonik. Bildphänomene der Schrift in kultur- und medienkomparativer Perspektive.”.
- Converted the initial manuscript from Microsoft Word to LaTeX.
- Added support and configured the packages for supporting contemporary CJK and several ancient scripts.
- Manually corrected typesetting and formatting issues in a document with more than 200 pages.
Student Assistant
Fraunhofer Institute for Open Communication Systems (FOKUS)
- Built a library for recognizing arbitrary cameras and capture cards; also configured camera parameters, and accessed image data using Microsoft DirectShow in C#.
- Developed calibration routines for multicamera systems.
Software Engineering Summer Intern
Fraunhofer Institute for Computer Architecture and Software Technology (FIRST) Internship Company NameFraunhofer Institute for Computer Architecture and Software Technology (FIRST)
- Created a library and sample applications for 3D gesture control of a digital dome using Microsoft Kinect and OpenNI.
Intern (Research)
DESY (German Electron Synchrotron)
- Set up and executed a continuously running two-week-long experiment to measure the weather-dependent intensity of cosmic rays and determine the half-life of muon particles using plate detectors and a weather station.
Intern (Research)
Humboldt University of Berlin
- Evaluated and visualized data on Z^0 resonance from the LEP experiment at CERN using C++ and the Root data analysis framework.
Experience
IGLU eLearning System
I presented it at the German youth science competition “Jugend forscht” and subsequently won the Berlin state competition in the category: work environment.
Cryptocurrency Trading Platform
In this (largely educational) project, we learned a lot about time series prediction, technical analysis as well as the microservice development and deployment (and we even made a small amount of profit).
CMS Administration and Theme Development
During my final two years in high school, I was a STEM ambassador and youth coordinator for the German STEM organization "MINT Zukunft schaffen" and, among other things, set up and managed a PHP-based forum system for them.
During my undergraduate studies, I also managed the CMS of my residential halls and worked on the main university WordPress website as well as event- and department-specific microsites. I managed the site content, created themes, extensions, and specific widgets—like an HTML 5 news carousel for the front page of the main university website replacing a previous Flash version.
MobX Emotion Theme Provider
https://github.com/gfmio/mobx-emotion-theme-providerResponsive React Monaco Editor
https://github.com/gfmio/responsive-react-monaco-editorGitHub Pages Boilerplate
https://github.com/gfmio/github-pages-boilerplateThis small project provides the boilerplate for building a React single-page web application using TypeScript and Webpack and deploying it to GitHub Pages with a single command.
TypeScript Error
https://github.com/gfmio/ts-errorThis extendable error class is compatible across all browsers (including all version of IE) and has the behavior of the error classes in the latest version of JavaScript.
Tenor I at London Contemporary Voices Kin Choir
https://www.youtube.com/watch?v=hgV_BljUA48We frequently have paid bookings at events and perform live with or do session recordings with professional artists like Kim Wilde, Shlomo, or Imogen Heap. During the summer, we perform at a number of music festivals in the UK and continental Europe.
Beyond just singing, I've also written choral arrangements of electronic music tracks and performed them with LCVK, such as "Monument" by Röyksopp & Robyn (linked) which now has nearly 16,000 views on Youtube (Feb 2019).
Digital Nomad
I spent most of my time abroad in Thailand, Vietnam, Japan, and New Zealand, but also traveled to Myanmar, South Korea, the US, and the Caribbean.
While abroad, I studied different programming language implementations as well as textbooks and research papers on programming languages, compiler design, and artificial intelligence which ultimately led to me starting work on my third tech startup, Automorph.
Service.js Application Framework
The core idea behind service.js is to structure applications as asynchronously communicating services, which encapsulate some part of the application functionality. The communication between the services is described using strongly typed, reusable protocols.
The services can then run in locally, in parallel, or remotely without any changes to the codebase. This renders changes to the application deployment trivial. The same services can be used in a standalone application, in a monolithic client-server backend or using microservices.
I started this project to simplify the development of microservice-based applications using TypeScript. The framework is currently under development and I hope to release version 1.0 in the first half of 2019.
Service.UI Component Framework
Service.UI currently uses the CSS-in-JS library emotion for theming and provides React components. The libraries are very small and each component, typically measuring less than 1KB in size each, can be used independently of the others, allowing overall bundle sizes to stay small.
Since the same concept can be applied to different environments, the library will be ported to React Native to support usage in mobile apps and Snabbdom which offers a faster and more lightweight alternative to React.
I started developing the development of this library due to the lack of good, small and easily configurable component libraries. The library is currently under development and I plan to release a stable version 1.0 in the first half of 2019.
Synaptic Wall
Education
Master of Science (MSc) Degree in Theoretical Physics (Quantum Fields and Fundamental Forces)
Imperial College London - London, United Kingdom
Bachelor of Science (BSc) Degree in Physics
Jacobs University Bremen - Bremen, Germany
Certifications
Deep Learning Specialization
Coursera
Sequence Models
Coursera
Convolutional Neural Networks
Coursera
Structuring Machine Learning Projects
Coursera
Improving Deep Neural Networks: Hyperparameter tuning, Regularization and Optimization
Coursera
Neural Networks and Deep Learning
Coursera
Certified Scrum Product Owner® (CSPO®)
Scrum Alliance®
Certified Scrum Master® (CSM®)
Scrum Alliance®
Skills
Libraries/APIs
REST APIs, React, Snabbdom, Node.js, MobX, Emotion Library, NumPy, Matplotlib, Chai, TensorFlow, LSTM, SQLAlchemy, Polyfill.io, SciPy, D3.js, CCXT, DirectShow, jQuery, jQuery UI, Kraken, Vuex, Rollup.js, Vue
Tools
Jira, Docker Compose, Docker Hub, Adobe Illustrator, Gulp, Adobe Photoshop, LaTeX, Mongoose, Adobe Creative Suite, NGINX, Mocha, Webpack, Webpack 4, Webpack 3, Jupyter, i3, Git, Bitbucket, Apache Airflow, Babel, Vagrant, Packer, Terraform, Adobe InDesign, Amazon Elastic Container Service (ECS), Amazon Elastic Container Registry (ECR), Moodle, Ansible, Apache, Geth (go-ethereum), Travis CI, CircleCI, Code Climate, Rollup, Codecov, Flink, RabbitMQ
Languages
ECMAScript (ES6), TypeScript, JavaScript, Python 3, HTML5, CSS3, Python, HTML, CSS, Sass, SCSS, YAML, PHP, SQL, Objective-C, Swift, Java, C, C++, C#, Scheme, Delphi, IDL
Frameworks
Express.js, Bootstrap, Svelte, Bulma, Electron, Spring, Cocoa, Redux, Flask, React Native, Laravel, OpenNI, Microsoft Kinect, Nuxt.js
Paradigms
RESTful Development, Functional Programming, Functional Reactive Programming, Object-oriented Programming (OOP), Agile Software Development, Continuous Integration (CI), Continuous Deployment, Continuous Delivery (CD), DevOps, Siamese Neural Networks, Test-driven Development (TDD)
Platforms
Amazon Web Services (AWS), Linux, MacOS, Docker, DigitalOcean, Arch Linux, Alpine Linux, Azure, Visual Studio Code (VS Code), Google Ads, X (formerly Twitter), OpenWRT, Azure Functions, Windows, iOS, Android, Kubernetes, Amazon EC2, Linode, WordPress, Joomla, Ethereum, Apache Flink, Apache Kafka
Storage
JSON, MySQL, MongoDB, Redis, OpenXML, PostgreSQL, Amazon S3 (AWS S3)
Other
Design Systems, Front-end Development, Full-stack, Leadership, Technical Leadership, Mobile Apps, CTO, CSS-in-JS, Styled-components, Software Development, Embedded Software, Serverless, IT Security, SVG, ParcelJS, Artificial Neural Networks (ANN), Backpropagation, Deep Learning, Neural Networks, Deep Neural Networks (DNNs), Hyperparameters, Hyperparameter Optimization, Machine Learning, Learning Transfer, Multi-task Learning, Facial Recognition, Convolutional Neural Networks (CNNs), Neural Style Transfer (NST), Recurrent Neural Networks (RNNs), Long Short-term Memory (LSTM), LSTM Networks, Eve, Facebook, Root Cause Analysis, Weather, LDAP, Azure Text to Speech, LLVM, Bitcoin, Bitcoind, Chrome Extensions, Web Extensions, Scraping, Web Scraping, AWS DevOps, Semantic Technology, Snyk
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