Sure, Lucid Lucidchart is awesome.

But have you considered these open source alternatives?

They are free, self-hostable and community-driven.

Check by yourself: Excalidraw  Excalidraw , diagrams.net  Draw.io , Mermaid  Mermaid Live Editor .

  1. So is Excalidraw Excalidraw

    Lavagna per disegnare schemi come fatti a mano

    ★ 88.3k diagram whiteboard License: MIT

    Una lavagna virtuale open source in stile disegnato a mano. Collaborativa e crittografata end-to-end.

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  2. So is diagrams.net Draw.io

    JavaScript, client-side editor for general diagramming

    ★ 51.8k diagram License: Apache-2.0

    Browser-based diagramming components and applications.

    preview

  3. So is Mermaid Mermaid Live Editor

    Modifica, visualizza in anteprima e condividi diagrammi/grafici mermaid

    ★ 4.4k diagram License: MIT

    Modifica, anteprima e condivisione di diagrammi/grafici mermaid.

    preview