Thanks.
We don't charge for our lessons because we didn't have to pay for most of what makes this site work. The list below is incomplete by design — these are the shoulders we are standing on.
The free infrastructure that hosts us
- Cloudflare Pages
Global CDN with unmetered bandwidth on the free tier. Every page you load comes through their edge.
- GitHub
Code hosting plus free Actions CI minutes for public repositories. Every commit you see was built and deployed for free.
- Google Fonts
Inter for Latin scripts; Noto Sans SC / JP / KR for Chinese, Japanese, Korean — delivered at no cost from their CDN.
The block-coding lineage
- Seymour Papert
Logo, constructionism, and the conviction that children can program. The grandfather of all of this.
- Mitchel Resnick & the MIT Media Lab Lifelong Kindergarten group
Scratch — the project that put block-based programming in front of millions of kids and proved the idea at scale.
- The Google Blockly team
The open-source library that renders, edits, and serializes every block in our workspace. We are a thin layer on top of their work.
- The Microsoft MakeCode team
The category-toolbox UX patterns we follow — accessible block coding for absolute beginners.
The open-source stack we build on
- Next.js (Vercel)
The static-export framework.
- React (Meta)
The rendering model.
- TypeScript (Microsoft)
The language that keeps us honest.
- Tailwind CSS
Adam Wathan and contributors — the styling system.
- Vitest, Testing Library, jsdom
The test stack our 100-plus tests run on.
- Howler.js
Goldfire Studios — the audio engine driving lesson narration.
- Firebase (Google)
Auth and Firestore on the free Spark tier.
- ffmpeg & music-metadata
The audio toolchain that stitches together our narration tracks.
And to every teacher who has ever sat down next to a beginner and said "the computer only does exactly what you tell it to" — this is the line we are still trying to teach.