#Langium has a new online showcase: after the state machine, we just added a second example DSL for arithmetic calculations. Try it right in your browser – the text editor is backed by a Langium-based language server running in a web worker.
https://langium.org/showcase/arithmetics/
Langium

Langium is an open source language engineering tool with first-class support for the Language Server Protocol, written in TypeScript and running in Node.js.

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