One docker-compose.yml: Cal.diy (the open-source Cal.com, built from source) + Chatwoot + Twenty CRM + shared PostgreSQL + Redis + Caddy.
Cal.com went closed source in April 2026. The self-hostable code is now calcom/cal.diy (MIT), with no published Docker image, so you build it locally.
Cal.diy keeps booking pages, calendar sync, the app store and webhooks. It dropped teams, round-robin, routing forms and Workflows, so this stack replaces Calendly Standard, not Calendly Teams.
Cal.diy's own site recommends it for personal, non-production use. Read the advisory before you put customer bookings on it.
Hosting: Liquid Web 8 GB Managed VPS, $100/mo regular ($50/mo for the first two months), checked 2026-09-26.
Most growth-stage teams stitch together Calendly for scheduling, Intercom for support chat and Salesforce for pipeline, then pay Zapier to connect them. This guide deploys the open-source equivalents on a single VPS: Cal.diy handles scheduling, Chatwoot handles conversations, and Twenty CRM tracks deals. When a prospect books a call, a webhook carries that booking into the support inbox and on into the CRM.
Measured idle RAM: ~3.0 GB; peak: ~4.5 GB on a 16 GB VPS
Minimum Liquid Web tier: 16 GB Managed VPS (~$30/mo)
HubSpot Marketing Hub Pro + CRM + Service Hub Pro: $800–$1,340+/mo; this stack: ~$30/mo
HubSpot charges separately for CRM, marketing automation, and customer support — and the Professional tier alone runs $800/mo before seat costs. This guide deploys all three functions with open-source equivalents: Twenty CRM for pipeline management, Mautic for email marketing and lead scoring, and Chatwoot for multi-channel support — on a single Liquid Web 16 GB VPS using one Compose file.
Requires a 16 GB VPS with a dedicated IP — Mautic alone needs 8 GB; adding Billionmail needs the extra headroom
Read the sustainability flags for both tools before committing: Billionmail is early-stage; Mautic has a documented 2026 funding crisis
Mailgun Flex + ActiveCampaign Plus (10k contacts): ~$110/mo; this stack: ~$40–$55/mo on Liquid Web
This guide pairs Billionmail (self-hosted SMTP server) with Mautic (marketing automation) on a single Liquid Web 16 GB VPS. Mautic handles contact segmentation, campaign flows, landing pages, and lead scoring. Billionmail provides the SMTP relay that Mautic sends through.
Minimum Liquid Web tier: 8 GB Managed VPS (~$33–$40/mo)
HubSpot Sales + Service Hub Pro (5 seats): ~$1,335/mo; this stack: ~$33/mo
HubSpot bundles CRM and customer support into one product at a significant price. This guide deploys the open-source equivalents — Twenty CRM for pipeline management and Chatwoot for multi-channel customer support — on a single Liquid Web 8 GB VPS using a single Compose file.
