https://main.direct/ Infrastructure-first B2B contact supply and email deliverability playbooks. en Fri, 16 Oct 2026 00:00:00 GMT https://main.direct/playbooks/contact-to-inbox/ https://main.direct/playbooks/contact-to-inbox/ Sat, 10 Oct 2026 00:00:00 GMT A five-layer B2B cold email architecture covering target definition, source mapping, contact validation, sending-domain isolation, warm-up and monitoring. https://main.direct/playbooks/self-supply/ https://main.direct/playbooks/self-supply/ Sat, 10 Oct 2026 00:00:00 GMT Public methodology for applying Main Direct's contact supply, validation and deliverability layer to itself.