n8n Gym At-Risk Alerts: Supabase + Gemini + Slack + Gmail

Automatically alert gym coaches and re-engage at-risk clients—daily

This n8n workflow scans your Supabase gym activity data every day to identify at-risk clients, generates a personalized re-engagement email draft with Google Gemini, notifies coaches in Slack, and emails clients via Gmail—while logging every alert back to Supabase and Google Sheets.

What this workflow does

• Runs on a daily schedule using an n8n schedule trigger.
• Loads active clients plus their relevant activity windows from Supabase: the last 14 days of check-ins and last 21 days of weekly form submissions.
• Merges and calculates engagement metrics per client (e.g., days since last check-in/form, weekly check-in count, missed activities), then determines a risk score/type and escalation/cooldown timing.
• Filters to high-risk clients and prevents duplicate spam by blocking alerts during a duplicate-alert cooldown window.
• Uses Google Gemini to create a short JSON email draft (subject + body) and formats a coach-facing Slack summary.
• Sends notifications: a Slack alert to the coach channel and a Gmail message to the client.
• Logs and syncs state: writes the risk event to Supabase (risk_events) and appends the same record to Google Sheets; then updates alert/escalation fields in Supabase and syncs them back to the client master sheet.

Use cases

• Identify clients missing expected check-ins/forms and trigger timely coach outreach.
• Automate re-engagement emails when attendance drops—without manual spreadsheet work.
• Maintain clean alert history with cooldowns, escalation timing, and synchronized reporting.

Technical details

• Supabase: reads from clients, checkins, weekly_forms; writes to risk_events and updates alert state/escalation fields.
• Google Gemini (PaLM): generates the email draft as JSON.
• Slack: posts coach-facing alerts and summaries.
• Gmail: sends the client email message.
• n8n nodes include: if, set, code, merge, slack, and gmail.