In the Summer of 2023, Penn Libraries (consisting of thirteen libraries, ten of which use course reserves) migrated our course reserves operations from Ares to Leganto. What was unusual about our migration is the fact that we do not use Primo; we have Blacklight as our discovery interface. We are the first library to implement Leganto with Blacklight. This presentation discusses our overall experience undertaking a Leganto implementation, and highlights the particular challenges of doing so without the Primo discovery layer. The anticipated presentation length is 20 minutes, with the rest of the time for Q&A and discussion.