Open-source software, with the fine print.

Real licenses, what the free edition leaves out, and project health for self-hosted software, checked against official sources.

A modern open-source CRM you can self-host and extend through its API.

SSO / SAMLPaidListed on the Organization plan and above, not on Pro. The pricing page does not say how this maps to the self-hosted edition.
Role-based access controlFreeRoles and field-level permissions are listed on all plans; row-level permissions are Organization and above. Self-hosted coverage not stated.
Audit logsPaidListed from the Organization plan up. Self-hosted mapping not stated.
Multi-user / teamsNot confirmedUser and workspace limits for free self-hosting are not stated in the pages read.
Backups and restoreNot confirmedDocs give a manual pg_dump and restore procedure with a cron example; no built-in backup tool.
API accessFreeREST and GraphQL APIs are listed on every plan, with rate limits on paid cloud plans. Webhooks also listed.
Support SLAPaidDedicated support and SLA are listed only on the Enterprise plan.