The Ceridwen Self Issue Client software can provide library users with the ability to check out books to themselves rather than relying on a staffed circulation desk. It presents a graphical interface to the library user and communicates with the back-end library system via a network.

The Ceridwen Self Issue Client software is Java based and supports any library system running the 3M SIP protocol (SIP2). It can also work with barcode readers and JavaCard compatible RFID readers. Whilst it can be made to work with security systems, it has a special Trust mode for libraries without a security system who just wish to allow their patrons to record when they have taken a book. It can also be configured to automatically run in an offline backup mode when the library system is unavailable.