PLDI 2025
Mon 16 - Fri 20 June 2025 Seoul, South Korea

Liquid types can express richer verification properties than simple type systems. However, despite their advantages, liquid types have yet to achieve widespread adoption. To understand why, we conducted a study analyzing developers’ challenges with liquid types, focusing on LiquidHaskell. Our findings reveal nine key barriers that span several categories, including developer experience, scalability challenges with complex and large codebases, and understanding the verification process. Together, these obstacles provide a comprehensive view of the challenges to the broader adoption of liquid types and offer insights that can inform the current and future design and implementation of liquid type systems.