Build a Slack-to-Linear Bridge in 30 Minutes

The build: in any Slack channel, reacting with a specific emoji on a message converts it to a Linear ticket with the right team, priority, and labels — auto-extracted from the message content.

Total build time: 30 minutes.

What you'll need

• Slack workspace (admin access to add an app)
• Linear with API access
• n8n
• AI API key

Step 1: Slack reaction trigger (8 min)

In Slack, create a custom app. Subscribe to reaction_added events. Point the webhook at n8n.

n8n Webhook trigger receives the event.

Filter: only act when the reaction is a specific emoji (I use :ticket: or :linear:).

Step 2: Fetch the original message (3 min)

The reaction event includes a reference to the original message. Add a Slack node to fetch the full message text + thread.

Step 3: AI extraction (10 min)

Add an AI node:

Convert this Slack message into a Linear ticket.

Message: {{ message_text }}
Channel: {{ channel_name }}
Thread context: {{ thread_text }}

Return JSON:
{
  "title": "<crisp 6-10 word title, action-oriented>",
  "description": "<2-4 paragraphs explaining the issue, including context from thread>",
  "team": <one of {YOUR_TEAMS}>,
  "priority": <"urgent" / "high" / "medium" / "low">,
  "labels": [up to 3 labels from {LABEL_LIST}],
  "estimate": <1 / 2 / 3 / 5 / 8>
}

Priority guidance:
- urgent: production down, customer-blocking, security
- high: significant friction, lots of users affected
- medium: improvements, minor bugs
- low: nice-to-have, cleanup

Be conservative on priority. Most things are medium.

Step 4: Create Linear ticket (5 min)

Add a Linear node. Action: create issue. Map all the fields from the AI response.

Add the Slack message permalink as a "source" field or to the description ("Original Slack message: ").

Step 5: Reply in Slack thread (3 min)

After creating the ticket, post a reply in the original Slack thread:

:ticket: Created Linear ticket: <{{ ticket_url }}|{{ ticket_id }}: {{ title }}>
Priority: {{ priority }} | Team: {{ team }}

Step 6: Test (3 min)

In any channel, post a fake bug report. React with :ticket:. Verify the Linear ticket appears with reasonable extraction.

Common gotchas

• Slack reaction events fire multiple times if the user toggles. Add idempotency check (have we created a ticket for this message_ts already?).
• Linear API requires specific team IDs, not team names. Build a lookup table.
• The AI's priority assessment will sometimes be too high. Add a one-line override in the Slack reply for triagers to adjust.

What I do with this

Anyone on the team can convert a Slack message to a Linear ticket with one click. Product, support, design, engineering. The ticket lands in the right team's queue with sane priority.

The previous workflow was: someone posts in Slack → someone else has to remember it → maybe someone makes a Linear ticket later → ticket is missing context.

The new workflow: one click. Ticket created. Context preserved. Source linked.

What to add next

• Different emoji for different teams (:eng-ticket: for engineering, :design-ticket: for design)
• Auto-assign based on who reacted
• Create as draft instead of full ticket if message is too ambiguous
• Weekly digest of all tickets created via this bridge

Start with the basic version. The other features earn their keep only after adoption is real.