The open-source Miro alternative

Miro grew into a workspace: boards, workshops, docs, video walkthroughs, and a marketplace of apps. That breadth is genuinely useful for facilitation-heavy teams, but if what you mostly make is diagrams (architecture sketches, flowcharts, org charts, plans) much of it is surface area you scroll past. livediagram starts from the diagram: shapes, arrows, and structure are the core of the product.

That focus shows up in the details. Arrows stay attached to shapes and re-route themselves as you move things, with collision avoidance so lines stop overlapping. Alignment guides and snapping keep layouts tidy without manual nudging. A format painter copies a style across elements, and style presets keep a diagram consistent. Bigger work splits across tabs inside one document, tabs group into folders, and each tab has Photoshop-style layers for separating annotation from content.

When the session needs more than a diagram, the same tab switches mode: Draw for freehand whiteboarding with pressure-sensitive markers, and Plan mode for boards of cards with WIP limits and quick add. A facilitator can run the room with a shared timer, dot-voting, live polls and a Q&A board, and event storming boards come with their own notation, including turning a photo of a sticky-note wall into notes.

Miro's free tier is real, but it's the top of a pricing funnel: board limits and gated features exist to move teams onto paid seats. livediagram has no paid tier and no plan to introduce one. The hosted version at livediagram.app is free, every user gets every feature, and there is nothing to upgrade to.

That's sustainable because the whole codebase is MIT-licensed and public. If you'd rather not depend on the hosted service at all, you can deploy the same code to your own Cloudflare account: the editor, the API, and the realtime collaboration all self-host, with no license keys and no phone-home checks.

In Miro, creating a board starts with an account, and anonymous guest editing depends on the plan you are on. In livediagram, collaborating is a URL. Anyone can create a document without signing up, share a link, and whoever opens it is on the canvas with you, live cursors and all. Share links can carry a password or an expiry date when you need them locked down.

The collaboration tools go beyond cursors: leave comments on elements and assign action items to teammates directly on the canvas, tracked together in the Collaborate panel, with optional email notifications. A selection lock shows when someone is editing an element, so two people rarely end up changing the same thing at once.

Diagrams rarely live alone. livediagram imports Mermaid (flowcharts, state and ER diagrams, the diagram-as-code format that lives in READMEs and AI output), Markdown outlines, Excalidraw scenes, draw.io files and Microsoft Whiteboard boards, and exports PNG, SVG, PDF, Mermaid, Markdown, Excalidraw or a portable JSON file. Any share link can be embedded as a read-only, live-updating iframe in a wiki or doc.

For programmatic use there is a free REST API with personal tokens and an MCP server at mcp.livediagram.app that lets AI assistants read and edit your documents directly; their edits arrive live, outlined, and undoable as one unit. None of it sits behind a plan.