ldap-carddav is a CardDAV server with a LDAP server as contacts and authentication backend. It has a major release published recently.

-- Features of ldap-carddav include 1. Create, edit, rename and delete contacts directly in LDAP server using CardDAV protocol. 2. Authenticate CardDAV users against LDAP server. 3. Multiple address book support. 4. Global and private address book support. 5. Bidirectional sync between LDAP server and CardDAV clients (contacts deleted directly in LDAP are deleted in CardDAV clients asynchronously). 6. Supports WebDAV sync. 7. Fully compatible (and can coexist) with LDAP address book applications. 8. Extensive and customizable configuration option to map vCard properties to LDAP attributes including multi-value and composite value properties and attributes. 9. Contact group support. 10. Media (like profile picture) support for contacts. 11. Caching support using popular backends like Memcached, APCu and file system.

Wiki: https://github.com/isubsoft/ldap-carddav/wiki