Charles Hoskinson, founder of Cardano, has praised the XRP Ledger's Unique Node List (UNL) design, describing it as a "well-reasoned system." During an X Spaces session with XRP community members and David Schwartz, former Ripple CTO, Hoskinson expressed gratitude for Schwartz's assistance during Cardano's Midnight glacier drop. He acknowledged the UNL system's clever approach to managing trust between validators, highlighting its use of negative UNLs to maintain network stability. Hoskinson noted that the experience of working with the XRP Ledger allowed his team to explore different blockchain designs, particularly focusing on how XRPL handles Byzantine agreement. Despite a disagreement on smart contracts, Hoskinson and Schwartz agreed on the utility of layer-1 smart contracts, with Schwartz emphasizing the importance of practical solutions like Midnight.