AI Workflow Developer — HR Onboarding Automation

We hire 30–50 people per quarter. Our onboarding is a mess — offer letters done manually in Word, IT provisioning tickets created by hand, first-week welcome emails copy-pasted from a Google Doc. We want a workflow that fires when a candidate is marked 'Accepted' in Greenhouse, and then: generates a personalised offer letter (via GPT from a template), creates IT provisioning tickets in Jira Service Desk, sends a welcome email sequence, and schedules the new hire's first-week meetings. Every step currently takes someone 20–40 minutes. We want all of it to take 0 minutes.