This library provides monad morphism utilities, most commonly used for manipulating monad transformer stacks.

This library provides the ability to launch and interact with external processes. It wraps around the process library, and intends to improve upon it.

This package provides Haskell bindings for the OpenGL graphics system (GL, version 4.5) and its accompanying utility library (GLU, version 1.3).

Shelly provides convenient systems programming in Haskell, similar in spirit to POSIX shells. Shelly is originally forked from the Shellish package.

This library provides Pure Haskell solver routines for use by the diagrams framework. It currently includes routines for finding real roots of low-degree (n < 5) polynomials, and solving tridiagonal and cyclic tridiagonal linear systems.

This package provides first class functional references. In addition to the usual operations of getting, setting and composition, plus integration with the state monad, lens families provide some unique features:

• Polymorphic updating

• Traversals

• Cast projection functions to read-only lenses

• Cast toList functions to read-only traversals

• Cast semantic editor combinators to modify-only traversals

For optimal first-class support use the lens-family package with rank 2/rank N polymorphism. Lens.Family.Clone allows for first-class support of lenses and traversals for those who require Haskell 98.

Difference lists are a list-like type supporting O(1) append. This is particularly useful for efficient logging and pretty printing (e.g. with the Writer monad), where list append quickly becomes too expensive.

Special values are provided by a SpecialValues typeclass. Those can be used for example by QuickCheck, see quickcheck-special.

Provides a FilePath datatype and utility functions for operating on it. Unlike the filepath package, this package does not simply reuse String, increasing type safety.

Zstandard compression packaged as a conduit. This is a very thin wrapper around the official hs-zstd interface.

A nonce is an arbitrary number used only once in a cryptographic communication. This package contain helper functions for generating nonces. There are many kinds of nonces used in different situations. It's not guaranteed that by using the nonces from this package you won't have any security issues. Please make sure that the nonces generated via this package are usable on your design.

This library provides a wide array of (semi)groupoids and operations for working with them. A Semigroupoid is a Category without the requirement of identity arrows for every object in the category. A Category is any Semigroupoid for which the Yoneda lemma holds. Finally, to work with these weaker structures it is beneficial to have containers that can provide stronger guarantees about their contents, so versions of Traversable and Foldable that can be folded with just a Semigroup are added.

This package provides a monad transformer version of the ST monad for strict state threads.

This library contains scalable timer functions provided by a timer manager.

This library provides a class for non-negative numbers, a wrapper which can turn any ordered numeric type into a member of that class, and a lazy number type for non-negative numbers (a generalization of Peano numbers).

This package contains a backend for ghc-persistent using the MySQL database server. Internally it uses the ghc-mysql-simple and mysql packages in order to access the database. This package supports only MySQL 5.1 and above. However, it has been tested only on MySQL 5.5. Only the InnoDB storage engine is officially supported.

This package contains a MonadRef type class that abstracts over the details of manipulating references, allowing one to write code that can operate in either the ST monad or the IO monad.

This Haskell library provides strict left folds that stream in constant memory, and you can combine folds using Applicative style to derive new folds. Derived folds still traverse the container just once and are often as efficient as hand-written folds.

This library provides adjunctions and representable functors for Haskell.

This package provides a commutative semigroup is a semigroup where the order of arguments to mappend does not matter.

This is an implementation of Tarjan's Union-Find algorithm (Robert E.: Tarjan. "Efficiency of a Good But Not Linear Set Union Algorithm",JACM 22(2), 1975) in order to maintain an equivalence relation. This implementation is a port of the union-find package using the ST monad transformer (instead of the IO monad).

This package provides a library to parse and render YAML documents.

This Hackage security library provides both server and client utilities for securing the Hackage package server. It is based on The Update Framework, a set of recommendations developed by security researchers at various universities in the US as well as developers on the Tor project.

This package provides bindings and types to bridge Haskell and <https://www.lua.org/ Lua>. . The full Lua interpreter version 5.4.4 is included. Alternatively, a system-wide Lua installation can be linked instead.