Open-Source Business Models — 6 Self-Hosted Alternatives

Six open-source alternatives to popular SaaS products — resellable, white-labelable, and proven as real businesses.


1. Cal.diy (formerly Cal.com) — Open-Source Calendly

  • Repo: github.com/calcom/cal.diy
  • Stars: ★45,282
  • Model: Fork it, white-label it, sell to dentists/lawyers for $200/mo
  • Proven: Founders hit $5M ARR in 3 years

2. Ghost — Open-Source Substack

  • Repo: github.com/TryGhost/Ghost
  • Stars: ★53,832
  • Model: Self-hosted Substack with 100% margin. 1,000 readers at 5/mo = 60K/yr
  • Proven: Used by major publishers, has managed hosting (Ghost Pro)

3. n8n — Open-Source Zapier

  • Repo: github.com/n8n-io/n8n
  • Stars: ★191,681
  • Model: Sell automation services at 500–2,000 per setup
  • Proven: Raised $14M; agency model behind it works at scale

4. Medusa — Open-Source Shopify

  • Repo: github.com/medusajs/medusa
  • Stars: ★34,228
  • Model: Take 5% on every sale. Zero rev share to Shopify
  • Proven: The most flexible open-source commerce platform

5. Listmonk — Open-Source Mailchimp

  • Repo: github.com/knadh/listmonk
  • Stars: ★21,421
  • Model: Send unlimited emails for AWS bill cost. Resell to agencies at 10x markup

6. Penpot — Open-Source Figma

  • Repo: github.com/penpot/penpot
  • Stars: ★49,403
  • Model: Sell self-hosted design tools to agencies who refuse client files in the cloud

The Pattern

All six follow the same playbook:

  1. Open-source the core product (free acquisition)
  2. Sell the self-hosted / white-label version to businesses who need control
  3. Or sell the managed cloud version to users who want convenience

Each is a proven $M+ ARR business, not just a GitHub project.