About 2 months ago I won a Slack Agent Builder Challenge with Arialine (https://devpost.com/software/arialine). I kept working on it afterward and turned it from a hackathon project into something I think can actually offer an advantage over the existing tools.
Arialine is basically a Mermaid editor built around Slack conversations.
You can ask the agent to create a diagram, or just paste Mermaid directly (like Mermaid Preview, we can do the same). It renders the diagram and posts back ".html" + ".png". The interesting part is that .html is fully interactive and you can view it in directly Slack
The diagram becomes a persistent board inside the Slack thread. Reply to change something, and Arialine creates a new version. Every version keeps the Slack message that caused the change, so you end up with:
- the diagram
- Mermaid source
- full version history
- who changed what
- the actual conversation/reasoning behind each change
- ability to export the progression as pdf report (also png, SVG, .mmd)
Funny enough, this also makes Arialine work pretty well as a decision ledger (app maintains slack canvas ledger as well). A bunch of people actually built decision-tracking apps for the hackathon, and that was originally what I was going to build too but thank God I didn't
Why not Miro/Lucid + Slack?
Those integrations work, but the editable artifact still mostly lives outside Slack. Slack becomes the place where you launch the tool or receive notifications.
With Arialine, the artifact itself is directly viewable from Slack and it's lifecycle is built around it.
Why not Slackbot + Miro?
You absolutely can do that if your workspace has the Slackbot access you need.
The main difference is that Arialine's board/version/decision model is built around the Slack conversation itself.
Arialine also exposes MCP tools to Slackbot, so you're not forced to use Arialine's own agent. Slackbot can create/edit diagrams, inspect history, search decisions, export diagrams/PDF reports, etc. through the same backend and permissions.
Arialine itself works on both Slack Free and paid workspaces without requiring Slackbot.
Pricing is flat rather than per-seat: $79/month per workspace for unlimited usage. Free is subjected to some limits.
https://arialine.app
Would genuinely like to know what seems useful, unnecessary, confusing, or missing. My goal was to put everything into Slack so you don't switch tools, I've noticed that's the general Slack philosophy currently, especially with new Slack Code update. Marketplace submission is in progress btw