Lars Melchior
Verified Expert in Engineering
Full-stack Developer
Berlin, Germany
Toptal member since July 15, 2020
Lars is a physicist, entrepreneur, and full-stack developer with 10 years of experience. Having built his own startup from scratch, he knows how to rapidly develop an MVP and bring a product to market. As an open-source library developer, he writes clean and maintainable code that's efficient and production-ready. Holding an MSc in physics, his strong research and analytical skills make him a valuable asset in almost any domain.
Portfolio
Experience
- C++ - 10 years
- Physics - 10 years
- Python - 8 years
- React Native - 4 years
- React - 4 years
- TypeScript - 4 years
- Node.js - 3 years
- WebAssembly (Wasm) - 2 years
Preferred Environment
Git, GitHub, Slack, SSH, Bash, Zsh, Visual Studio Code (VS Code), Xcode, Linux, MacOS, Emscripten, Jupyter Notebook, Python, Matplotlib, SciPy, NumPy, Fastlane, React Native, React, Express.js, Node.js, JavaScript, TypeScript, CMake, C++
The most amazing...
...app I've built is Maphi, a math learning app that uses an innovative drag and drop interface to help anyone understand algebra intuitively.
Work Experience
Senior Full-stack Developer
Freelance Clients
- Built the recruitment app for a large government body that helps candidates understand and prepare for the screening process. It included gamified exercises to help candidates evaluate their mental and physical conditions for the role.
- Helped an educational platform understand and solve performance issues on their web platform, assisting them drastically in reducing their initial response time.
- Developed a chrome extension that added much-desired extra features to third-party networking websites, which integrated perfectly into their existing UI.
- Helped investors estimate the technological value of one of their portfolio projects.
Co-founder and Full-stack Developer
Edutapps
- Conceptualized, built, and released Maphi, the cross-platform mobile app for learning and practicing algebra using intuitive drag-and-drop gestures.
- Built an algebra system based on commutative and associative pattern matching, specializing in manual interaction and generating step-by-step solutions to mathematical problems.
- Developed a platform-independent game engine in OpenGL and C++ with bindings to SDL, React Native, and WebAssembly, supporting 2D vector rendering and multi-touch input.
- Built the company's website at https://maphi.app and an interactive browser math engine at https://engine.maphi.app.
- Implemented app analytics and A/B testing using Firebase.
- Won several startup pitch competitions and secured a pre-seed investment funding round.
Scientific Software Engineer
Deepspin
- Developed the company's infrastructure to run experiments on the main MRI prototype. Experiments were run in a dynamic, full-stack application, driven with a RESTful server written in Flask and a dynamic front end written in React.
- Built the infrastructure for measuring magnetic fields with high precision, requiring controlling a robot and Tesla Meter, using serial port communication and optimization algorithms for accurate localization and corrections.
- Built C++/Python drivers for the MRI prototype's easy configuration, communication, and synchronization of the DAC/ADC cards for sequence controlling and data acquisition.
- Derived and implemented algorithms for the noise canceling used to increase the signal-to-noise ratio on the MRI prototype.
- Incentivized and helped the software team implement many software development best practices to create more stable and reliable software. These included continuous integration, type systems, linters, code reviews, etc.
Student Research Assistant
Geog-August Universität Göttingen
- Designed, implemented, and published the X-ray optics simulation toolkit, PyPropagate, for performing static and time-resolved X-ray high wave propagation simulations.
- Participated in and evaluated synchrotron experiments with results published as papers in the Journal of Applied Crystallography and Optics Express.
- Ported evaluation and visualization frameworks written in MATLAB to C++ and Python, obtaining much better performance and using only FOSS.
- Tutored physics undergraduates in programming courses, teaching and evaluating their C++ and numerics skills.
Experience
Maphi
ModernCppStarter
https://github.com/TheLartians/ModernCppStarterCPM.cmake
https://github.com/cpm-cmake/CPM.cmakePyPropagate
https://github.com/TheLartians/PyPropagateLarsPlot
Fit | The Nonlinear Regression App
Education
Master's Degree in Physics
Georg-August Universität Göttingen - Göttingen, Germany
Bachelor's Degree in Physics
Georg-August Universität Göttingen - Göttingen, Germany
Skills
Libraries/APIs
React, NumPy, Mypy, Node.js, SciPy, Matplotlib, OpenGL, OpenGL ES, REST APIs, Setuptools, SymPy, PyTorch, Flask-RESTful, Quartz 2D
Tools
Git, Slack, GitHub, LaTeX, CMake, Apple Motion, Affinity Designer, Adobe Photoshop, Emscripten, Asana, Xcode, MATLAB, Mathematica, Fastlane, Zsh, Expo
Languages
C++, TypeScript, Python, Objective-C, Lua, JavaScript, CSS, HTML, Bash, C, Kotlin
Frameworks
React Native, Express.js, Flask, Next.js, Angular, Chrome
Paradigms
Unit Testing, Refactoring, Concurrent Programming, Test-driven Development (TDD), Mobile Development, Gamification, REST
Platforms
Firebase, Android, iOS, MacOS, Linux, Jupyter Notebook, Visual Studio Code (VS Code)
Storage
MongoDB, MySQL, SQLite, PostgreSQL
Other
Mathematics, Physics, Computational Physics, Science, Numerical Simulations, Biophysics, Computer Algebra Systems, Visualization, Physics Simulations, Computational Biology, X-ray Optics, Education Technology (Edtech), Full-stack, Genetic Algorithms, Research, Parsers, LLVM, Software Engineering, Computational Biological Physics, Neural Networks, Artificial Neural Networks (ANN), Gatsby, WebAssembly (Wasm), Neuroscience, Startups, APIs, Minimum Viable Product (MVP), Mobile Apps, SSH, Machine Learning, Boost.Python, Styled-components, Poetry, Robotics, Hardware, Analog-to-digital Converters (ADC), Digital-to-analog Converters (DAC), Soldering, Electronics, PyBind11, Objective-C++, User Experience (UX), Algorithms, Numerical Methods, Optics, 3D Visualization, Dependency Management, Optimization, Chrome Extensions
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