Polysemy is a high-performance, zero-boilerplate effect system for Haskell, designed to simplify the handling of side effects in functional programs. Unlike traditional monad transformer stacks, Polysemy uses a modern approach based on freer monads and interpreters, allowing developers to define, compose, and interpret effects in a more modular and testable way. It aims to offer both flexibility and performance without sacrificing type safety or expressiveness.

Features

  • Defines effects as pure Haskell data types
  • Enables modular, composable effect handlers
  • Avoids monad transformer boilerplate
  • Supports runtime and compile-time interpreters
  • Promotes testability by mocking effects
  • Designed for high performance and clarity

Project Samples

Polysemy Screenshot 1

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Categories

Libraries

License

BSD License

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Additional Project Details

Programming Language

Haskell

Related Categories

Haskell Libraries

Registered

2025-07-17
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