"Every good mathematician is at least half a philosopher, and every good philosopher is at least half a mathematician."
Attributed to Gottlob Frege


My name is Theodore Chu. I also go by Theo, Ted, and Teddy, but I always introduce myself as Theodore. I am a United States citizen.

I'm a philosopher, mathematician, and technologist in the San Francisco Bay Area. I enjoy creating free and open-source productivity tools and writing documentation for open-source projects.


I'm still trying to figure out what I want to do for my career. I'm currently pursuing software engineering. In the meantime, I'm trying to do my part to ensure that our technology, government policies, and institutional practices respect and protect our rights, freedoms, and liberties.


My formal training has been focused on philosophy, mathematics, and science. I expect to earn a bachelor's degree in Mathematics and Philosophy (double major) in May 2021. My independent studies are focused on computer science and technology with an emphasis on web development and information security. I like to read, but I read slowly. You can find some of the books I've read here.


I write in English and develop unofficial editor extensions for Standard Notes, a free, open-source, and end-to-end encrypted notes app that is a safe place for your notes, thoughts, and life's work. You can my writing published on the Standard Notes Blog and copied on my blog.

The editors that I build are available for free and licensed under AGPL-3.0-or-later. The source code for each is available on GitHub. The most popular of my editors is called the Append Editor. The Append Editor has been downloaded hundreds of times since November 2020 when the counting started. You can try it at demo.appendeditor.com and read more about it at appendeditor.com.

  • Append Editor (demo, docs) - Write GitHub Flavored Markdown via four different editing modes: Plain Textarea with spell check, in-line formatting provided by CodeMirror, what-you-see-is-what-you-get live formatting provided by the Rich Markdown Editor developed by Outline, and in-line syntax highlighting provided by the Monaco Editor. In addition to GFM, the Plain Textarea, CodeMirror, and Monaco modes support KaTeX, table of contents, footnotes, in-line HTML, and emoji codes. The Monaco mode also supports autocompletion, search and replace, and syntax highlighting for over 60 programming languages. The Append Editor has built-in support for printing notes and per-note font sizes, font families, and custom CSS.
  • Flashcard Editor  (demo, docs) - Study flashcards in private with KaTeX and Markdown.
  • Marp Editor  (demo, docs) - Create presentation slides with Marp and Marpit Markdown.
  • Music Editor (demo, docs) - Write music with VexTab and VexFlow.


I support free and open source projects that help people communicate and spread information. The free flow of information is important to democracy. I contribute financially to Ghost, Docusaurus, and Wiki.js. My contributions are via Open Collective and GitHub Sponsors. I also donate to Signal, Cryptomator, and Wikipedia.


Please see my contact page.


Please see my photos page.

Social media is poison. Please proceed with caution.


I would like to thank all of my friends, family, teachers, readers, and colleagues for all of their support throughout my years. I would not be where I am now without them.

Nonetheless, all of my opinions are my own and not necessarily, in any way, endorsed or shared by them or anyone else connected to me.

Give a Tip

If you like what I do or support my goals, please consider supporting me by sponsoring me or giving me a tip. All of your support helps me maintain my free and open-source projects and pay for my domains and web hosting.

If you would like to support a particular cause, topic, or project, please let me know and I will do my best to accommodate.

You can also support me emotionally and intellectually by telling me what you think about my work.

Affiliates and Referrals

These are some services that I like or support. If you sign up for them using these links, you may get discounts or I may get additional product or a slice of the sales.

  • DigitalOcean - a cloud hosting service with an intuitive control panel, intuitive control panel, predictable pricing, team accounts, and more.
  • StandardNotes - an open-source and end-to-end encrypted notes app
  • ProtonMail - probably the best secure, encrypted email service
  • Dynadot - one of my preferred domain registrars


You can see the stats for my websites on Plausible, a simple and privacy-friendly alternative to Google Analytics: