Weekly HubSpot pipeline forecast to Sheets and Slack

Build me a code workflow that runs every Monday at 7:00am America/New_York and produces a deterministic weekly pipeline forecast snapshot. It should be reproducible, no LLM judgement needed.

Step 1: Use HubSpot List Pipelines to fetch all active deal pipelines and their stages, including each stage's win probability.

Step 2: Use HubSpot Search Deals to pull every open deal across those pipelines, paginating through all pages of results. Request the properties dealname, amount, dealstage, pipeline, and closedate. Treat any deal whose stage is not closed-won and not closed-lost as open.

Step 3: In code, bucket each deal by (pipeline, stage). For each bucket compute deal_count, total_amount (sum of amount), and weighted_forecast (sum of amount times the stage's win probability). Use the stage probability from HubSpot by default.

Step 4: Use Google Sheets Append Values to append one row per (week, pipeline, stage) to a tracking tab. The week key should be the ISO week start date in America/New_York. Columns: week_start, pipeline_name, stage_name, deal_count, total_amount, weighted_forecast, week_over_week_delta. Compute week_over_week_delta by reading the most recent prior row for the same pipeline and stage and subtracting its weighted_forecast from this week's.

Step 5: Use Slack Send a Message to post a compact summary to the revenue channel. Include the total weighted forecast across all pipelines, the change vs last week (absolute and percent), and the top three (pipeline, stage) buckets that contributed the largest absolute swing. Format it tightly with bold headers and a short bullet list.

Make the spreadsheet ID, tracking tab name, Slack channel, and timezone configurable inputs. Log a final summary line with total deals processed, pipelines covered, and total weighted forecast so it's easy to verify the run.