invariant alternatives and similar packages

Based on the "Control" category.
Alternatively, view invariant alternatives based on common mentions on social networks and blogs.

rio-orphans

9.9 3.6 invariant VS rio-orphans

A standard library for Haskell
machines

9.8 4.0 invariant VS machines

Networks of composable stream transducers

Less time debugging, more time building

Scout APM allows you to find and fix performance issues with no hassle. Now with error monitoring and external services monitoring, Scout is a developer's best friend when it comes to application development.

Promo scoutapm.com

fused-effects

9.8 8.3 invariant VS fused-effects

A fast, flexible, fused effect system for Haskell
transient

9.8 0.0 invariant VS transient

A full stack, reactive architecture for general purpose programming. Algebraic and monadically composable primitives for concurrency, parallelism, event handling, transactions, multithreading, Web, and distributed computing with complete de-inversion of control (No callbacks, no blocking, pure state)
mtl

9.8 5.6 invariant VS mtl

The Monad Transformer Library
funflow

9.8 4.2 invariant VS funflow

Functional workflows
pipes

9.8 3.5 invariant VS pipes

Compositional pipelines
capability

9.7 1.2 invariant VS capability

Extensional capabilities and deriving combinators
recursion-schemes

9.7 4.3 invariant VS recursion-schemes

Generalized bananas, lenses and barbed wire
apecs

9.7 4.0 invariant VS apecs

a fast, extensible, type driven Haskell ECS framework for games
distributed-closure

9.6 0.0 invariant VS distributed-closure

Serializable closures for distributed programming.
foldl

9.6 2.5 invariant VS foldl

Composable, streaming, and efficient left folds
selective

9.6 4.2 invariant VS selective

Selective Applicative Functors: Declare Your Effects Statically, Select Which to Execute Dynamically
record

9.6 0.0 invariant VS record

Anonymous records
free

9.6 4.8 invariant VS free

free monads
classy-prelude-yesod

9.5 4.7 invariant VS classy-prelude-yesod

Type classes for mapping, folding, and traversing monomorphic containers
freer-simple

9.5 3.1 invariant VS freer-simple

A friendly effect system for Haskell
classy-prelude

9.5 4.7 invariant VS classy-prelude

Type classes for mapping, folding, and traversing monomorphic containers
safe-exceptions

9.5 0.0 invariant VS safe-exceptions

Safe, consistent, and easy exception handling
extensible-effects

9.5 0.0 invariant VS extensible-effects

Extensible Effects: An Alternative to Monad Transformers
auto

9.5 0.0 invariant VS auto

Haskell DSL and platform providing denotational, compositional api for discrete-step, locally stateful, interactive programs, games & automations. http://hackage.haskell.org/package/auto
ComonadSheet

9.4 0.0 invariant VS ComonadSheet

A library for expressing "spreadsheet-like" computations with absolute and relative references, using fixed-points of n-dimensional comonads.
transient-universe

9.4 0.0 invariant VS transient-universe

A Cloud monad based on transient for the creation of Web and reactive distributed applications that are fully composable, where Web browsers are first class nodes in the cloud
abstract-par

9.4 1.8 invariant VS abstract-par

Type classes generalizing the functionality of the 'monad-par' library.
hask

9.4 0.0 invariant VS hask

Category theory for Haskell with a lens flavor (you need GHC 7.8.3, not 7.8.2 to build this!)
these

9.4 3.4 invariant VS these

An either-or-both data type, with corresponding hybrid error/writer monad transformer.
unliftio

9.4 4.9 invariant VS unliftio

The MonadUnliftIO typeclass for unlifting monads to IO
retry

9.4 3.1 invariant VS retry

Retry combinators for monadic actions that may fail
frpnow

9.3 0.0 invariant VS frpnow

Principled practical FRP
cloud-haskell

9.2 0.0 invariant VS cloud-haskell

This is an umbrella development repository for Cloud Haskell
either

9.2 1.0 invariant VS either

the EitherT monad transformer
distributed-fork

9.2 0.0 invariant VS distributed-fork

A distributed data processing framework in Haskell.
parallel

9.2 3.5 invariant VS parallel

a library for parallel programming
deepseq

9.2 6.4 invariant VS deepseq

Deep evaluation of data structures
distributed-process-platform

9.2 0.0 invariant VS distributed-process-platform

DEPRECATED (Cloud Haskell Platform) in favor of distributed-process-extras, distributed-process-async, distributed-process-client-server, distributed-process-registry, distributed-process-supervisor, distributed-process-task and distributed-process-execution
monad-validate

9.1 0.0 invariant VS monad-validate

A Haskell monad transformer library for data validation
tardis

9.1 0.0 invariant VS tardis

Bidirectional state monad transformer
monad-time

9.1 0.0 invariant VS monad-time

Type class for monads which carry the notion of the current time.
ifcxt

9.1 0.0 invariant VS ifcxt

constraint level if statements
monad-control

9.1 1.0 invariant VS monad-control

Lift control operations, like exception catching, through monad transformers
contravariant

9.1 3.6 invariant VS contravariant

Haskell 98 contravariant functors
operational

9.0 2.3 invariant VS operational

Implement monads by specifying instructions and their desired operational semantics.
errors

9.0 1.7 invariant VS errors

Type-safe error handling
exceptions

9.0 2.9 invariant VS exceptions

mtl friendly exceptions
lens-tutorial

9.0 0.0 invariant VS lens-tutorial

The missing tutorial module for the lens library
freer-effects

9.0 0.0 invariant VS freer-effects

An implementation of "Freer Monads, More Extensible Effects".
motor

8.9 0.0 invariant VS motor

Type-safe effectful state machines in Haskell
effect-monad

8.9 0.0 invariant VS effect-monad

Provides 'graded monads' and 'parameterised monads' to Haskell, enabling fine-grained reasoning about effects.
ixmonad

8.9 0.0 invariant VS ixmonad

Provides 'graded monads' and 'parameterised monads' to Haskell, enabling fine-grained reasoning about effects.
mmorph

8.9 1.5 invariant VS mmorph

Monad morphisms