TypeCell: End-User Programming in Block-Based rich text documents
summary
TypeCell is a block-based rich text editor that embeds a live reactive TypeScript/JavaScript environment so users can program documents that evaluate-as-you-type and import libraries from npm. The core reactive layer is implemented in about 30 lines of JavaScript using MobX, supporting cross-document composability and a demoed flow to register block plugins (example: a Map block with persisted properties and a WYSIWYG settings panel). Worked demos include live cross-document updates and LLM-assisted parsing; challenges include local vs shared execution state and mutable side effects.
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chapters (19)
- 0:00TypeCell motivation
- 1:25Hackability and reactivity
- 2:30Live demo of editor
- 5:06Core engine with MobX
- 7:15Reactivity challenges
- 7:35Extensibility in spreadsheets
- 8:41Custom components
- 10:53Plugin system
- 11:55No-code customization
- 13:27Comparison with notebooks
- 14:10Liveness and composability
- 14:55Inline code extraction
- 16:23Road trip planning demo
- 18:12LLMs for structured data
- 20:17Local state challenges
- 21:40UX primitives
- 22:22Type system for plugins
- 23:27Open source future
- 24:09Q&A
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