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 # Payments Dashboard
 
-AWS SAM application that ingests payment CSVs, syncs check data with Bank of America CashPro APIs, and surfaces an outstanding-payments dashboard in Slack.
+AWS SAM application that ingests payment CSVs, syncs check data with Bank of America CashPro APIs, processes Gusto payroll confirmation emails into Slack notifications, and surfaces an outstanding-payments dashboard in Slack.
 
 ## Architecture
 
-- **ProcessPaymentCsv** - Lambda triggered by S3 CSV upload. Parses payments, upserts to DynamoDB, and submits new/cancelled checks to the CashPro Check Management API.
-- **FetchBoaTransactions** - Scheduled Lambda (weekdays 9am ET). Calls the CashPro Previous Day Transaction Inquiry API and matches cleared/returned checks back to DynamoDB records.
-- **SlackAppHome** - Lambda behind API Gateway. Renders the payments dashboard on the Slack App Home tab with outstanding aging buckets and drill-down modals.
+- **ProcessPayrollEmail** — Lambda triggered by S3 (inbound email) and SQS (batch timer). SES receives Gusto payroll emails at `payroll@int.seahaven.com`, stores them to S3, and this Lambda parses the email body, extracts financial data, and posts a combined Slack notification (employee payroll + contractor payments) after a 10-minute batching window. Runs outside VPC.
+- **ProcessPaymentCsv** — Lambda triggered by S3 CSV upload. Parses Stampli payment exports, upserts to DynamoDB, and submits new/cancelled checks to the CashPro Check Management API.
+- **FetchBoaTransactions** — Scheduled Lambda (weekdays 9am ET). Calls the CashPro Previous Day Transaction Inquiry API and matches cleared/returned checks back to DynamoDB records.
+- **SlackAppHome** — Lambda behind API Gateway. Renders the payments dashboard on the Slack App Home tab with outstanding aging buckets and drill-down modals.
 
-All three Lambdas run inside a VPC with a NAT Gateway for a static outbound IP (required by BoA IP whitelisting).
+ProcessPaymentCsv, FetchBoaTransactions, and SlackAppHome run inside a VPC with a NAT Gateway for a static outbound IP (required by BoA IP whitelisting). ProcessPayrollEmail runs outside the VPC.
+
+## Payroll Email Pipeline
+
+Gusto sends payroll confirmation emails when payroll is run. A Gmail filter on adam@seahavenind.com auto-forwards emails from `automated@gusto.com` and `gustonoreply@gusto.com` to `payroll@int.seahaven.com`.
+
+**Flow:** Gmail forward → SES receipt rule → S3 bucket → Lambda parses email → DynamoDB (pending) → SQS delay queue (10 min) → Lambda batches all pending items for that date → single Slack message → DynamoDB (notified)
+
+**Deduplication:** Each email is deduplicated by DynamoDB key (`PAYROLL_EMAIL#employee#<date>` or `PAYROLL_EMAIL#contractor#<date>#<bank-suffix>`). The batch post is deduplicated by `PAYROLL_BATCH#<date>`. All items have a 90-day TTL.
 
 ## BoA CashPro API Integration