Arialine

Arialine is the Mermaid diagram tool and AI diagram generator for Slack. Type /arialine and paste Mermaid, or describe a system in plain language, and get a PNG and an interactive HTML diagram in the channel: flowcharts, sequence diagrams, C4 architecture, ER, Gantt, mindmaps and every Mermaid 12 type. Write "@Arialine diagram what we decided" and the Slack discussion becomes the diagram. Edit by replying in the thread; every change becomes a version linked to the Slack message, author and date behind it, with undo, rewind and branches, and Arialine explains why each element exists. Markdown files become native Slack canvases with Mermaid blocks drawn as images. Export PNG, SVG, .mmd and PDF. Works from Slackbot via MCP.

Unlike Miro or Lucidchart, there is no separate whiteboard and no per-seat price. Unlike Mermaid Preview, the diagram stays editable with saved source and versions. Unlike Mermaid Live Editor or draw.io, the diagram and its history stay in Slack. Built for architecture reviews, incident postmortems, runbooks, onboarding and roadmaps. Free plan with every feature; Team is one flat price per workspace, on every Slack plan.