Libraries for writing Plutus Tx scripts

This auction example shows a relatively low-level way of writing scripts using Plutus Tx. In practice, you may consider using a higher-level library that abstracts away some of the details. For example, plutus-apps provides a constraint library for writing Plutus Tx. Using these libraries, writing a validator in Plutus Tx becomes a matter of defining state transactions and the corresponding constraints, e.g., the condition refundsPreviousHighestBid can simply be written as Constraints.mustPayToPubKey bidder (lovelaceValue amt).