Leads, stages, notes, follow-up dates, won/lost tracking. HubSpot CRM is free but sends all your data to HubSpot. This stays on your server.
Unlimited leads, email logging, pipeline analytics, import/export. Self-hosted on your hardware, no usage caps, no phone-home, your data stays on disk forever.
One ~13MB binary. No Docker, no dependencies, no background daemons.