David Baumgold, Developer in Amsterdam, Netherlands
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David Baumgold

Verified Expert  in Engineering

Open Source Developer

Amsterdam, Netherlands
Toptal Member Since
July 23, 2017

David is a web developer who is truly full-stack. Front-end JavaScript, API integration, web application programming, databases, server administration, security, and automated testing fall into his wheelhouse. He prefers to work in Python when possible and has extensive experience with Django and Flask on the back end. On the front-end, he's a React wiz and uses Redux and GraphQL to build complex, dynamic browser-based applications.


Cassini Technologies
Python, FastAPI, SQLAlchemy, React, React Router, Playwright, Pydantic
Ribbon Home
Python, JavaScript, TypeScript, Django, Amazon Web Services (AWS), GraphQL...
GitHub Actions, GitHub, APIs, Flask, Python, Architecture, Web Development...




Preferred Environment

GitLab, GitHub, Visual Studio Code (VS Code), MacOS, Mapbox

The most amazing...

...project I've worked on is an extension for the Flask web framework which makes OAuth a snap—what usually takes 200+ lines of code can be done in ten.

Work Experience

Senior Full-stack Developer

2023 - 2024
Cassini Technologies
  • Rearchitected the front-end system to use modern, open-source components, like React Router.
  • Organized back-end codebase, increasing maintainability, and automated test coverage.
  • Worked with customer representatives to design, architect, and build new features to fit their needs.
Technologies: Python, FastAPI, SQLAlchemy, React, React Router, Playwright, Pydantic

Senior Full-stack Developer

2021 - 2022
Ribbon Home
  • Converted a homegrown front-end component library to an open-source Chakra UI component library.
  • Refactored a database representation of core data to improve the consistency and reliability of database queries.
  • Mentored junior developers to help them learn how to write reliable code with automated tests.
Technologies: Python, JavaScript, TypeScript, Django, Amazon Web Services (AWS), GraphQL, Architecture, Web Development, Team Leadership, Full-stack

Senior Software Developer

2017 - 2021
  • Shipped products that earned millions of dollars in ARR.
  • Migrated a large codebase from Python 2 to Python 3.
  • Mentored other junior developers on my team by reviewing their code and answering questions.
  • Demonstrated and presented best practices for faster, high-quality development.
Technologies: GitHub Actions, GitHub, APIs, Flask, Python, Architecture, Web Development, Team Leadership, Full-stack

Senior Front-end Developer

2017 - 2018
  • Led a small team to develop a dynamic React-based front-end for the Impraise web application.
  • Assisted in migrating from a legacy REST-based backend to one based on GraphQL.
  • Mentored other developers in how to properly use GraphQL.
Technologies: Apollo, GraphQL, Redux, React, Web Development, Full-stack

Web Developer

2017 - 2017
MIT Office of Digital Learning
  • Worked in a team to develop an interactive website where MOOC learners could find information about their courses.
  • Created a new code base to replace a legacy website for hosting video files. The new code base used AWS for hosting and transcoding video files.
  • Wrote automated tests in Python (pytest framework) and React (Enzyme framework).
  • Assisted in prioritizing features, based on feedback from users and past experience.
  • Assisted in running Scrum meetings and increased team productivity.
Technologies: Amazon Web Services (AWS), Open edX, Redux, React, Django, Web Development, EdX

Software Developer | Developer Advocate

2013 - 2016
  • Led the development of major components of the Open edX course management system.
  • Organized the open source community around Open edX and facilitated communication and collaboration among community members.
  • Created automated tools to increase visibility and efficiency in planning and executing development work.
  • Assisted in planning and architecting components of the Open edX system.
  • Ran the release process for the Open edX software—testing the release candidates and organizing bug fixes as necessary.
Technologies: GitHub, Node.js, Django, Python, Open edX, Web Development, EdX

Software Engineer

2011 - 2013
  • Assisted with a major architectural restructuring to work with App Engine’s eventually-consistent data store.
  • Increased developer productivity through communication, education, tooling, and automated testing.
  • Advocated for more reliable development techniques, such as automated testing.
  • Provided constructive criticism to help my coworkers improve the quality of their code.
  • Refactored major components of the application to be more maintainable and performant.
Technologies: Google App Engine, Django, Python, Web Development

Software Engineer

2010 - 2011
  • Fixed UI bugs as reported by customers.
  • Wrote and debugged data loaders for various airlines.
  • Implemented features based on data-driven prioritization.
  • Manually tested and verified changes, both for myself and my coworkers.
Technologies: Java, JavaScript, PHP, Web Development

Junior Systems Administrator (Guru)

2007 - 2010
Brandeis University Computer Science Department
  • Handled the installation and updates for all servers and desktop workstations owned by the computer science department.
  • Assisted students and faculty with routine account maintenance, such as password resets.
  • Created RPM packages for existing software for the ease of installation and management.
  • Tracked, prioritized, and resolved support requests from the faculty.
  • Scripted and automated many routine tasks associated with server management, including patching security vulnerabilities.
Technologies: Security, Bash Script, Linux Server Administration


An open source project for setting up OAuth authentication with the Flask web framework.

This allows you to build a website that allows logging in with Facebook, Google, Twitter, GitHub, and many other websites—all in about 20 lines of code.

N-queens Problem Solution

My goal was to gain a deep understanding of the well-known n-queens problem and provide a meticulously documented solution that elucidates the underlying logic. In developing this code, utmost attention was given to ensure not only its correctness but also its exceptional readability.

Bot for Integrating GitHub and JIRA

At edX, project management spans two different websites: JIRA for planning and reporting work, and GitHub for writing and reviewing code to execute the work.

Many people spent many tedious hours keeping these two websites in sync, so I wrote a bot to do so automatically. This bot listens for activity on GitHub pull requests and records it in linked JIRA issues. It also listens for when JIRA issues change state and updates the state on linked GitHub pull requests.
2006 - 2010

Bachelor's Degree in Psychology

Brandeis University - Waltham, MA, USA

2006 - 2010

Master's Degree in Computer Science

Brandeis University - Waltham, MA, USA


Moment.js, SQLAlchemy, REST APIs, jQuery, Backbone.js, React, Node.js, Lodash, Pydantic, React Router, Playwright


GitHub, Git, Pytest, Homebrew, Apt-get, Travis CI, Docker Compose, NGINX, GitLab, React Apollo, Vim Text Editor, Babel, Webpack


Nose, Flask, Django, Django REST Framework, Bootstrap 3, Redux, Sphinx Documentation Generator, Bootstrap, Jasmine


TypeScript, CSS, HTML, ECMAScript (ES6), JavaScript, Python 3, Python, PHP, SQL, Java, Bash Script, GraphQL


Automated Testing, Scrum, Functional Programming


Linux, Open edX, MacOS, Google App Engine, Amazon Web Services (AWS), Docker, Amazon EC2, Visual Studio Code (VS Code), Mapbox


Amazon S3 (AWS S3), PostgreSQL, MySQL


Code Review, Python Mockups, Web App Security, Regular Expressions, SSH, Tech Conferences, Open Source, Technical Documentation, Conference Speaking, APIs, Back-end Development, Architecture, Web Development, Full-stack, FastAPI, Server Security, Server Administration, Enzyme, Security, EdX, Wagtail CMS, Developer Relations, Technical Training, Front-end Development, Web Applications, Linux Server Administration, GitHub Actions, Apollo, Team Leadership, Development

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