GitHub - Microsoft/pxt: Microsoft MakeCode (PXT - Programming eXperience Toolkit)
"Microsoft MakeCode is based on the open source project Microsoft Programming Experience Toolkit (PXT). Microsoft MakeCode is the name in the user-facing editors, PXT is used in all the GitHub sources.
- a Blockly-based code editor along with converter to the text format
- a Monaco code editor that powers VS Code
- extensibility support to define new blocks in TypeScript