warmbly · Agentic cold email

Warmbly

Warmbly is an open-source cold email and mailbox warmup platform from warmbly, described in its README as agentic and AI-native. It runs multi-step campaigns from mailboxes the user already owns and warms them using a pool of monitored mailboxes. It also includes a unified inbox, a CRM, deliverability tracking and integrations with HubSpot, Slack and Zapier. The AI features the README mentions are visual reply playbooks with AI steps and a shared live workspace where teams and their agents work together, but it does not say which models or agent capabilities are involved. Architecturally, a control plane (backend API, Postgres, Redis, event bus) owns all state, while interchangeable Go workers send and sync mail through each mailbox's own provider. It self-hosts on Docker Compose with a one-line install script and needs no cloud account. It is licensed Apache-2.0, has 521 stars, and the latest release listed is v0.6.70 (31 October 2026).