Despite the intended use for prototyping or as a first step towards giving semantics to a new programming language, interpreters are often monolithic and difficult to extend. Higher-order effects and handlers promise modular composition of handlers and semantics; in practice, however, they have been mostly applied to toy examples. We present an approach that successfully combines algebraic, scoped, and latent effects into a handler pipeline for interpreting the functional logic programming language Curry. We show which effects make up Curry, discuss the infrastructure needed to combine effects of different classes and shed light on how these effects interact in order to lessen the barrier to entry for using effects in practical projects.

We present an approach for automatic function inversion in Haskell. The inverse functions we generate are based on an extension of Haskell's computational model with non-determinism and free variables. We implement this functional logic extension of Haskell via a monadic lifting of functions and type declarations. Using inverse functions, we additionally show how Haskell's pattern matching can be augmented with support for functional patterns, which enable arbitrarily deep pattern matching in data structures. Finally, we provide a plugin for the Glasgow Haskell Compiler to seamlessly integrate inverses and functional patterns into the language, covering almost all of the Haskell2010 language standard.