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new file mode 100644
--- /dev/null
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diff --git a/README.md b/README.md
new file mode 100644
--- /dev/null
+++ b/README.md
@@ -0,0 +1,147 @@
+# 🚒 Rescue
+## More Understandable Error Handling
+
+![Continuous Integration](https://github.com/fission-suite/fission/workflows/Continuous%20Integration/badge.svg)
+![License](https://img.shields.io/github/license/expede/rescue)
+
+`rescue` is an experimental error handling library for Haskell.
+
+The standard library approach to error handling is to use an existential type to
+_subclass_ any error as `SomeException`. This is very convenient 
+(requires nealy zero set up), and matches what  developers expect coming from 
+other ecosystems.
+
+A core goal of `rescue` is to give the programmer clarity about which execptions
+are possible at any given point in the code. We achieve this by using (open) variants
+for compositon rather than inheritance. We hide the detail as much as posisble,
+and attempt to make this work in a flexible, constraint-driven style as much 
+as possible.
+
+Perhaps there is some value in treating these more separately. 
+There is an old distinction that mirrors the above as errors (irrecoverable) 
+vs exceptions (recoverable).
+
+`rescue` breaks the problem into synchronous and asynchoronous exceptions.
+This distinction allows us to express our assumptions about the error 
+environment, separate modes of handling for the same monadic stack, 
+and even different errors.
+
+# Goals
+
+Our goals are to have:
+
+* Clarity of what errors can be raised by some code
+* Not need a large tree of error types for our application (set-like)
+* Way to declare assumptions about which errrors are available
+  * e.g. "can raise X, Y, and Z", or "raises exactly X and Y but none others"
+* Extensible
+* Ability to call code that raises some subset of errors
+
+# Approach
+
+The closest approach is `MonadError`, except that our implementation uses 
+type-level lists for flexiblity,  and hides the exception parameter from the 
+class constraint as a type family.  `rescue` also splits `raise` and `attempt` 
+into separate classes to help us more granularly express the effects available 
+in the current context. 
+
+## Class Heirarchy
+
+1. `MonadRaise` -- roughly `MonadThrow`
+2. `MonadRescue` -- roughly `MonadCatch`
+3. `MonadCleanup` -- roughly `MonadBracket`
+
+`Monad m => MonadRaise m => MonadRescue m => MonadCleanup m`
+
+## Errors / Asynchronous Exceptions
+
+An asynchronous error (e.g. coming from another thread)
+comes with a lot more uncertainty. We may not be aware of the type of error
+being thrown to us, or when it's thrown (since the runtime will interrupt).
+The purpose of this scenraio is typically to cleanup some resource 
+and immeditely rethrow.
+
+While a more structured, type-driven style would be appreciated here, this is
+fundamentally how the runtime works. As such, we do need to contend 
+with `SomeAsyncException`s.
+
+The good news is that we're not expected to do much with them. Essentially all
+we care about is:
+
+* _That_ an async exception interrupted our flow, 
+* We should not attempt recovery
+* The error should be rethrown
+
+Cleanup is also a use case for synchronous exceptions. If something is thrown
+inside a context with an open resource, we should clean that up.
+
+The basic flow for an async execption is then:
+
+1. An async exception is raised
+2. Convert it to a synchronous exception 
+3. Run the normal cleanup
+4. Rethrow the original asynchronous error
+
+This means that any instacne of MonadAsyncCleanup needs a MonadCleanup and `Raises m SomeAsyncException`
+
+# FAQ
+
+## Why another typeclass?
+
+It's true that MonadThrow is totally pervasive. However, not trying to 
+
+There's also nothing stopping us from writing a function of the type
+
+```haskell
+fromThrow :: (MonadCatch m, MonadRaise n) => m a -> n a
+```
+
+...though the conversion from `SomeException` would take a bit of care.
+
+## Why avoid `SomeException`?
+
+`SomeException` is typesafe, but very difficult to track by hand.
+In fact, with async exceptions, you may need to handle an error interrupting
+your execution _even if you don't have a `MonadThrow`_ in your context.
+
+By treating exceptions as something visible and tarckable (though hidden
+when you don't need it), we gain a lot of ability to reason about our program,
+and avoid writing lots of nested `Either`s.
+
+## Does this do async exception handling?
+
+It does! `MonadCleanup` is the typeclass, and it has very few instances.
+It's essentially [`MonadBracket`](https://www.fpcomplete.com/blog/2017/02/monadmask-vs-monadbracket/),
+but with explicit errors.
+
+This separation of the `SomeException` and `OpenUnion` can help determine the
+intention of the exception. `SomeException` (and `SomeAsyncException`) are really
+more like errors -- things that should fail and not be recovered from. In a world
+with async exceptions, the cleanest way to respond to an error is to stop
+our execution, cleanup any resources, and propogate the error.
+
+## Are there other packages attempting to solve this problem?
+
+Yep! For instance, [`safe-exceptions`](https://hackage.haskell.org/package/safe-exceptions).
+They distinguish between three kinds of exceptions:
+
+> We're going to define three different versions of exceptions. Note that these definitions are based on how the exception is thrown, not based on what the exception itself is:
+>
+>    **Synchronous** exceptions are generated by the current thread. What's important about these is that we generally want to be able to recover from them. For example, if you try to read from a file, and the file doesn't exist, you may wish to use some default value instead of having your program exit, or perhaps prompt the user for a different file location.
+>
+>    **Asynchronous** exceptions are thrown by either a different user thread, or by the runtime system itself. For example, in the async package, race will kill the longer-running thread with an asynchronous exception. Similarly, the timeout function will kill an action which has run for too long. And the runtime system will kill threads which appear to be deadlocked on MVars or STM actions.
+>
+>    In contrast to synchronous exceptions, we almost never want to recover from asynchronous exceptions. In fact, this is a common mistake in Haskell code, and from what I've seen has been the largest source of confusion and concern amongst users when it comes to Haskell's runtime exception system.
+
+>    **Impure** exceptions are hidden inside a pure value, and exposed by forcing evaluation of that value. Examples are error, undefined, and impureThrow. Additionally, incomplete pattern matches can generate impure exceptions. Ultimately, when these pure values are forced and the exception is exposed, it is thrown as a synchronous exception.
+>
+>    Since they are ultimately thrown as synchronous exceptions, when it comes to handling them, we want to treat them in all ways like synchronous exceptions. Based on the comments above, that means we want to be able to recover from impure exceptions.
+
+...along with some general guidance...
+
+>   All synchronous exceptions should be recoverable
+>   All asynchronous exceptions should not be recoverable
+>   In both cases, cleanup code needs to work reliably
+
+Rescue is primarily focused on deligering a great experince when dealing with 
+synchronous excpetions, though touches on async ones as well. 
diff --git a/Setup.hs b/Setup.hs
new file mode 100644
--- /dev/null
+++ b/Setup.hs
@@ -0,0 +1,2 @@
+import Distribution.Simple
+main = defaultMain
diff --git a/benchmark/Main.hs b/benchmark/Main.hs
new file mode 100644
--- /dev/null
+++ b/benchmark/Main.hs
@@ -0,0 +1,12 @@
+module Main where
+
+import Criterion
+import Criterion.Main
+
+main :: IO ()
+main = defaultMain
+  [ bgroup "Textable.encode" encode
+  ]
+
+encode :: [Benchmark]
+encode = []
diff --git a/doctest/Main.hs b/doctest/Main.hs
new file mode 100644
--- /dev/null
+++ b/doctest/Main.hs
@@ -0,0 +1,10 @@
+module Main (main) where
+
+import           System.FilePath.Glob (glob)
+
+import           Test.DocTest (doctest)
+import           Test.QuickCheck ()
+import           Test.QuickCheck.Instances ()
+
+main :: IO ()
+main = doctest =<< glob "./library"
diff --git a/library/Control/Monad/Cleanup.hs b/library/Control/Monad/Cleanup.hs
new file mode 100644
--- /dev/null
+++ b/library/Control/Monad/Cleanup.hs
@@ -0,0 +1,30 @@
+-- | Cleanly release resources and clean up contexts
+
+module Control.Monad.Cleanup
+  ( retry
+  , always
+  -- * Reexport
+  , module Control.Monad.Rescue
+  , module Control.Monad.Cleanup.Class
+  ) where
+
+import           Control.Monad.Cleanup.Class
+import           Control.Monad.Rescue
+
+import           Numeric.Natural
+
+-- | Equivalent of 'finally'
+always :: MonadCleanup m => m a -> m b -> m a
+always action finalizer =
+  cleanup (pure ())
+          (\_ _ -> finalizer)
+          (\_   -> finalizer)
+          (\_   -> action)
+
+retry :: MonadCleanup m => Natural -> m a -> m a
+retry 0     action = action
+retry times action =
+  cleanup (pure ())
+          (\_ _ -> retry (times - 1) action)
+          (\_   -> pure ())
+          (\_   -> action)
diff --git a/library/Control/Monad/Cleanup/Class.hs b/library/Control/Monad/Cleanup/Class.hs
new file mode 100644
--- /dev/null
+++ b/library/Control/Monad/Cleanup/Class.hs
@@ -0,0 +1,18 @@
+{-# LANGUAGE FlexibleContexts #-}
+{-# LANGUAGE TypeFamilies     #-}
+
+module Control.Monad.Cleanup.Class (MonadCleanup (..)) where
+
+import           Control.Exception
+import           Control.Monad.Rescue
+
+import           Data.WorldPeace
+
+-- | Safely work with resources when an asynchronous exception may be thrown
+class (Raises m SomeException, MonadRescue m) => MonadCleanup m where
+  cleanup
+    :: m resource                                   -- ^ Acquire some resource
+    -> (resource -> OpenUnion (Errors m) -> m _ig1) -- ^ Cleanup and re-raise
+    -> (resource ->                         m _ig2) -- ^ Cleanup normally
+    -> (resource ->                         m a)    -- ^ Inner action to perform with the resource
+    -> m a
diff --git a/library/Control/Monad/Raise.hs b/library/Control/Monad/Raise.hs
new file mode 100644
--- /dev/null
+++ b/library/Control/Monad/Raise.hs
@@ -0,0 +1,99 @@
+{-# LANGUAGE AllowAmbiguousTypes #-}
+{-# LANGUAGE FlexibleContexts    #-}
+{-# LANGUAGE ScopedTypeVariables #-}
+{-# LANGUAGE TypeFamilies        #-}
+
+-- | Monadic raise semantics & helpers
+
+module Control.Monad.Raise
+  ( ensure
+  , ensureM
+
+  -- * Class Reexports
+
+  , module Control.Monad.Raise.Class
+  , module Control.Monad.Raise.Constraint
+
+  -- * Data Reexports
+
+  , module Data.WorldPeace.Subset.Class
+  ) where
+
+import           Control.Monad.Raise.Class
+import           Control.Monad.Raise.Constraint
+
+import           Data.WorldPeace.Subset.Class
+
+-- $setup
+--
+-- >>> :set -XDataKinds
+-- >>> :set -XFlexibleContexts
+-- >>> :set -XMonoLocalBinds
+-- >>> :set -XTypeFamilies
+-- >>> :set -XTypeOperators
+-- >>>
+-- >>> import Control.Monad.Trans.Rescue
+-- >>> import Data.Proxy
+-- >>> import Data.Result
+-- >>> import Data.WorldPeace
+-- >>>
+-- >>> data FooErr  = FooErr  deriving Show
+-- >>> data BarErr  = BarErr  deriving Show
+-- >>> data QuuxErr = QuuxErr deriving Show
+
+-- | Lift a pure error (@Either@) into a @MonadRaise@ context
+-- i.e. Turn @Left@s into @raise@s.
+--
+-- ==== __Examples__
+--
+-- >>> :{
+--   mayFail :: Int -> Either FooErr Int
+--   mayFail n =
+--     if n > 50
+--       then Left FooErr
+--       else Right n
+-- :}
+--
+-- >>> :{
+--   goesBoom :: (MonadRaise m, m `Raises` FooErr) => m Int
+--   goesBoom = do
+--     first  <- ensure $ mayFail 100
+--     second <- ensure $ mayFail 42
+--     return $ second * 10
+-- :}
+--
+-- >>> goesBoom :: Result '[FooErr, BarErr] Int
+-- Left (Identity FooErr)
+ensure :: (MonadRaise m, Raises m inner) => Either inner a -> m a
+ensure (Right val) = pure val
+ensure (Left err)  = raise err
+
+-- | A version of @ensure@ that takes monadic actions
+--
+-- ==== __Examples__
+--
+-- >>> :{
+--   mayFailM :: Monad m => Int -> m (Either (OpenUnion '[FooErr, BarErr]) Int)
+--   mayFailM n =
+--     return $ if n > 50
+--       then Left (openUnionLift FooErr)
+--       else Right n
+-- :}
+--
+-- >>> :{
+--   foo :: (MonadRaise m, RaisesOnly m '[FooErr, BarErr]) => m Int
+--   foo = do
+--     first  <- ensureM $ mayFailM 100
+--     second <- ensureM $ mayFailM first
+--     return (second * 10)
+-- :}
+--
+-- >>> runRescue (foo :: Rescue '[FooErr, BarErr] Int)
+-- Left (Identity FooErr)
+ensureM
+  :: ( MonadRaise m
+     , Raises     m inner
+     )
+  => m (Either inner a)
+  -> m a
+ensureM action = ensure =<< action
diff --git a/library/Control/Monad/Raise/Class.hs b/library/Control/Monad/Raise/Class.hs
new file mode 100644
--- /dev/null
+++ b/library/Control/Monad/Raise/Class.hs
@@ -0,0 +1,162 @@
+{-# LANGUAGE DataKinds            #-}
+{-# LANGUAGE FlexibleContexts     #-}
+{-# LANGUAGE FlexibleInstances    #-}
+{-# LANGUAGE MagicHash            #-}
+{-# LANGUAGE TypeFamilies         #-}
+{-# LANGUAGE UndecidableInstances #-}
+
+-- | The 'MonadRaise' class, which is an effect for
+--   early escape / happy path programming with an exception side channel
+
+module Control.Monad.Raise.Class (MonadRaise (..)) where
+
+import           Control.Exception
+
+import           Control.Monad.Catch.Pure
+import           Control.Monad.Cont
+
+import           Control.Monad.ST
+
+import           Control.Monad.Trans.Except
+import           Control.Monad.Trans.Identity
+import           Control.Monad.Trans.Maybe
+import           Control.Monad.Trans.Reader
+
+import qualified Control.Monad.RWS.Lazy       as Lazy
+import qualified Control.Monad.RWS.Strict     as Strict
+
+import qualified Control.Monad.State.Lazy     as Lazy
+import qualified Control.Monad.State.Strict   as Strict
+
+import qualified Control.Monad.Writer.Lazy    as Lazy
+import qualified Control.Monad.Writer.Strict  as Strict
+
+import           Data.Kind
+import           Data.WorldPeace
+import           Data.WorldPeace.Subset.Class
+
+import           GHC.Base
+import           GHC.Conc
+import           GHC.IO
+
+-- $setup
+--
+-- >>> :set -XDataKinds
+-- >>> :set -XFlexibleContexts
+-- >>> :set -XTypeApplications
+--
+-- >>> import Data.WorldPeace
+
+-- | Raise semantics, like a type-directed @MonadThrow@.
+--   Not unlike @MonadError@ with an in-built open variant.
+class Monad m => MonadRaise m where
+  type Errors m :: [Type]
+
+  -- | Raise an error
+  --
+  -- The @Proxy@ gives a type hint to the type checker.
+  -- If you have a case where it can be inferred, see 'Control.Monad.Raise.raise''.
+  --
+  -- ==== __Examples__
+  --
+  -- >>> data FooErr  = FooErr  deriving Show
+  -- >>> data BarErr  = BarErr  deriving Show
+  -- >>> data QuuxErr = QuuxErr deriving Show
+  -- >>>
+  -- >>> type MyErrs  = '[FooErr, BarErr]
+  -- >>>
+  -- >>> :{
+  --  goesBoom :: Int -> Either (OpenUnion MyErrs) Int
+  --  goesBoom x =
+  --    if x > 50
+  --      then return x
+  --      else raise FooErr
+  -- :}
+  --
+  -- >>> goesBoom 42
+  -- Left (Identity FooErr)
+  --
+  -- >>> :{
+  --  maybeBoom :: Int -> Maybe Int
+  --  maybeBoom x =
+  --    if x > 50
+  --      then return x
+  --      else raise ()
+  -- :}
+  --
+  -- >>> maybeBoom 42
+  -- Nothing
+  raise :: Subset err (OpenUnion (Errors m)) => err -> m a
+
+instance MonadRaise [] where
+  type Errors [] = '[()]
+  raise _ = []
+
+instance MonadRaise Maybe where
+  type Errors Maybe = '[()]
+  raise _ = Nothing
+
+instance MonadRaise (Either (OpenUnion errs)) where
+  type Errors (Either (OpenUnion errs)) = errs
+  raise = Left . include
+
+instance MonadRaise IO where
+  type Errors IO = '[IOException]
+  raise = IO . raiseIO#
+
+instance MonadRaise (ST s) where
+  type Errors (ST s) = '[IOException]
+  raise = GHC.IO.unsafeIOToST . raise
+
+instance MonadRaise STM where
+  type Errors STM = '[IOException]
+  raise = STM . raiseIO#
+
+instance (MonadRaise m, Contains (Errors m) errs)
+  => MonadRaise (ExceptT (OpenUnion errs) m) where
+    type Errors (ExceptT (OpenUnion errs) m) = errs
+    raise = ExceptT . pure . raise
+
+instance MonadRaise m => MonadRaise (IdentityT m) where
+  type Errors (IdentityT m) = Errors m
+  raise = lift . raise
+
+instance MonadRaise m => MonadRaise (MaybeT m) where
+  type Errors (MaybeT m) = Errors m
+  raise = lift . raise
+
+instance MonadRaise m => MonadRaise (ReaderT cfg m) where
+  type Errors (ReaderT cfg m) = Errors m
+  raise = lift . raise
+
+instance MonadRaise m => MonadRaise (CatchT m) where
+  type Errors (CatchT m) = Errors m
+  raise = lift . raise
+
+instance MonadRaise m => MonadRaise (ContT r m) where
+  type Errors (ContT r m) = Errors m
+  raise = lift . raise
+
+instance MonadRaise m => MonadRaise (Lazy.StateT s m) where
+  type Errors (Lazy.StateT s m) = Errors m
+  raise = lift . raise
+
+instance MonadRaise m => MonadRaise (Strict.StateT s m) where
+  type Errors (Strict.StateT s m) = Errors m
+  raise = lift . raise
+
+instance (MonadRaise m, Monoid w) => MonadRaise (Lazy.WriterT w m) where
+  type Errors (Lazy.WriterT w m) = Errors m
+  raise = lift . raise
+
+instance (MonadRaise m, Monoid w) => MonadRaise (Strict.WriterT w m) where
+  type Errors (Strict.WriterT w m) = Errors m
+  raise = lift . raise
+
+instance (MonadRaise m, Monoid w) => MonadRaise (Lazy.RWST r w s m) where
+  type Errors (Lazy.RWST r w s m) = Errors m
+  raise = lift . raise
+
+instance (MonadRaise m, Monoid w) => MonadRaise (Strict.RWST r w s m) where
+  type Errors (Strict.RWST r w s m) = Errors m
+  raise = lift . raise
diff --git a/library/Control/Monad/Raise/Constraint.hs b/library/Control/Monad/Raise/Constraint.hs
new file mode 100644
--- /dev/null
+++ b/library/Control/Monad/Raise/Constraint.hs
@@ -0,0 +1,24 @@
+{-# LANGUAGE ConstraintKinds  #-}
+{-# LANGUAGE FlexibleContexts #-}
+{-# LANGUAGE TypeFamilies     #-}
+
+-- | Declare which exceptions may be raised/rescued in a given context
+module Control.Monad.Raise.Constraint
+  ( Raises
+  , RaisesAtLeast
+  , RaisesOnly
+  ) where
+
+import           Control.Monad.Raise.Class
+
+import           Data.WorldPeace
+import           Data.WorldPeace.Subset.Class
+
+-- | Raises this exception, but potentially others
+type Raises m err = Subset err (OpenUnion (Errors m))
+
+-- | May raise errors, including the provided list
+type RaisesAtLeast m errs = Subset (OpenUnion errs) (OpenUnion (Errors m))
+
+-- | Restrict exceptions to exactly this list
+type RaisesOnly m errs = errs ~ Errors m
diff --git a/library/Control/Monad/Rescue.hs b/library/Control/Monad/Rescue.hs
new file mode 100644
--- /dev/null
+++ b/library/Control/Monad/Rescue.hs
@@ -0,0 +1,103 @@
+{-# LANGUAGE LambdaCase   #-}
+{-# LANGUAGE TypeFamilies #-}
+
+-- | Rescue semantics & helpers
+--
+-- Essentially a type-directed version of 'Control.Monad.Catch'.
+--
+-- This is the opposite of 'Control.Monad.Raise', which embeds en error.
+-- 'Rescue' takes a potential error out of the surrounding context
+-- and either handles or exposes it.
+
+module Control.Monad.Rescue
+  ( rescue
+  , reattempt
+  , onRaise
+  , lastly
+
+  -- * Reexports
+
+  , module Control.Monad.Raise
+  , module Control.Monad.Rescue.Class
+  ) where
+
+import           Data.Result.Types
+import           Data.WorldPeace
+
+import           Control.Monad.Raise
+import           Control.Monad.Rescue.Class
+
+import           Numeric.Natural
+
+-- $setup
+--
+-- >>> :set -XDataKinds
+-- >>> :set -XFlexibleContexts
+-- >>> :set -XTypeApplications
+--
+-- >>> import Control.Monad.Trans.Rescue
+-- >>> import Data.Proxy
+-- >>> import Data.WorldPeace as OpenUnion
+--
+-- >>> data FooErr  = FooErr  deriving Show
+-- >>> data BarErr  = BarErr  deriving Show
+-- >>> data QuuxErr = QuuxErr deriving Show
+
+-- | Handle all exceptions
+--
+-- >>> type MyErrs = '[FooErr, BarErr]
+-- >>> myErrs = Proxy @MyErrs
+--
+-- >>> :{
+-- goesBoom :: Int -> Rescue MyErrs String
+-- goesBoom x =
+--   if x > 50
+--     then return (show x)
+--     else raise FooErr
+-- :}
+--
+-- >>> handler = catchesOpenUnion (\foo -> "Foo: " <> show foo, \bar -> "Bar:" <> show bar)
+-- >>> rescue (goesBoom 42) (pure . handler)
+-- RescueT (Identity (Right "Foo: FooErr"))
+rescue
+  :: ( MonadRescue m
+     , RaisesOnly  m errs
+     )
+  => m a
+  -> (OpenUnion errs -> m a)
+  -> m a
+rescue action handler = either handler pure =<< attempt action
+
+onRaise
+  :: ( MonadRescue m
+     , RaisesOnly  m errs
+     )
+  => (OpenUnion errs -> m ())
+  -> m a
+  -> m (Result errs a)
+onRaise errHandler action =
+  attempt action >>= \case
+    Left err -> do
+      errHandler err
+      return $ Err err
+
+    Right val ->
+      return $ Ok val
+
+-- | 'retry' without asynchoronous exception cleanup.
+--   Useful when not dealing with external resources that may
+--   be dangerous to close suddenly.
+reattempt :: MonadRescue m => Natural -> m a -> m a
+reattempt 0     action = action
+reattempt times action =
+  attempt action >>= \case
+    Left  _   -> reattempt (times - 1) action
+    Right val -> return val
+
+-- | Run an additional step, and throw away the result.
+--   Return the result of the action passed.
+lastly :: (Contains (Errors m) (Errors m), MonadRescue m) => m a -> m b -> m a
+lastly action finalizer = do
+  errOrOk <- attempt action
+  _       <- finalizer
+  ensure errOrOk
diff --git a/library/Control/Monad/Rescue/Class.hs b/library/Control/Monad/Rescue/Class.hs
new file mode 100644
--- /dev/null
+++ b/library/Control/Monad/Rescue/Class.hs
@@ -0,0 +1,158 @@
+{-# LANGUAGE FlexibleContexts     #-}
+{-# LANGUAGE FlexibleInstances    #-}
+{-# LANGUAGE LambdaCase           #-}
+{-# LANGUAGE TypeFamilies         #-}
+{-# LANGUAGE UndecidableInstances #-}
+
+-- | The 'MonadRescue' class, meant for retrieving the success/failure branches
+
+module Control.Monad.Rescue.Class (MonadRescue (..)) where
+
+import           Data.Functor
+
+import           Data.WorldPeace
+
+import           Exception
+
+import           Control.Monad.Raise.Class
+import           Control.Monad.Raise.Constraint
+
+import           Control.Monad.Cont
+
+import           Control.Monad.Trans.Except
+import           Control.Monad.Trans.Identity
+import           Control.Monad.Trans.Maybe
+import           Control.Monad.Trans.Reader
+
+import qualified Control.Monad.RWS.Lazy         as Lazy
+import qualified Control.Monad.RWS.Strict       as Strict
+
+import qualified Control.Monad.State.Lazy       as Lazy
+import qualified Control.Monad.State.Strict     as Strict
+
+import qualified Control.Monad.Writer.Lazy      as Lazy
+import qualified Control.Monad.Writer.Strict    as Strict
+
+import           Data.WorldPeace.Subset.Class
+
+-- $setup
+--
+-- >>> :set -XDataKinds
+-- >>> :set -XFlexibleContexts
+-- >>> :set -XTypeApplications
+--
+-- >>> import Control.Monad.Trans.Rescue
+-- >>> import Data.Proxy
+-- >>> import Data.WorldPeace as OpenUnion
+--
+-- >>> data FooErr  = FooErr  deriving Show
+-- >>> data BarErr  = BarErr  deriving Show
+-- >>> data QuuxErr = QuuxErr deriving Show
+
+-- | Pull a potential error out of the surrounding context
+class MonadRaise m => MonadRescue m where
+  -- | Attempt some action, exposing the success and error branches
+  --
+  --  ==== __Examples__
+  --
+  --  >>> :{
+  --    goesBoom :: Int -> Rescue '[FooErr, BarErr] Int
+  --    goesBoom x =
+  --      if x > 50
+  --        then return x
+  --        else raise FooErr
+  -- :}
+  --
+  -- >>> runRescue . attempt $ goesBoom 42
+  -- Right (Left (Identity FooErr))
+  --
+  -- Where @Identity fooErr@ is the selection of the 'OpenUnion'.
+  -- In practice you would handle the 'OpenUnion' like so:
+  --
+  -- >>> let handleErr = catchesOpenUnion (show, show)
+  -- >>> let x = attempt (goesBoom 42) >>= pure . either handleErr show
+  -- >>> runRescue x
+  -- Right "FooErr"
+  attempt :: m a -> m (Either (OpenUnion (Errors m)) a)
+
+instance MonadRescue Maybe where
+  attempt = return . \case
+    Nothing -> Left $ openUnionLift ()
+    Just x  -> Right x
+
+instance MonadRescue [] where
+  attempt = return . \case
+    []      -> Left $ include ()
+    (a : _) -> Right a
+
+instance MonadRescue (Either (OpenUnion errs)) where
+  attempt action = Right action
+
+instance MonadRescue IO where
+  attempt action =
+    tryIO action <&> \case
+      Right val  -> Right val
+      Left ioExc -> Left $ include ioExc
+
+instance MonadRescue m => MonadRescue (MaybeT m) where
+  attempt (MaybeT action) = MaybeT . fmap sequence $ attempt action
+
+instance MonadRescue m => MonadRescue (IdentityT m) where
+  attempt (IdentityT action) = lift (attempt action)
+
+instance
+  ( MonadRescue m
+  , Contains (Errors m) errs
+  )
+  => MonadRescue (ExceptT (OpenUnion errs) m) where
+  attempt (ExceptT action) =
+    lift $
+      attempt action <&> \case
+        Left err       -> Left $ include err
+        Right errOrVal -> errOrVal
+
+instance MonadRescue m => MonadRescue (ReaderT cfg m) where
+  attempt = mapReaderT attempt
+
+instance (Monoid w, MonadRescue m) => MonadRescue (Lazy.WriterT w m) where
+  attempt = Lazy.mapWriterT runner2
+
+instance (Monoid w, MonadRescue m) => MonadRescue (Strict.WriterT w m) where
+  attempt = Strict.mapWriterT runner2
+
+instance MonadRescue m => MonadRescue (Lazy.StateT s m) where
+  attempt = Lazy.mapStateT runner2
+
+instance MonadRescue m => MonadRescue (Strict.StateT s m) where
+  attempt = Strict.mapStateT runner2
+
+instance (Monoid w, MonadRescue m) => MonadRescue (Lazy.RWST r w s m) where
+  attempt = Lazy.mapRWST runner3
+
+instance (Monoid w, MonadRescue m) => MonadRescue (Strict.RWST r w s m) where
+  attempt = Strict.mapRWST runner3
+
+instance MonadRescue m => MonadRescue (ContT r m) where
+  attempt = withContT $ \b_mr current -> b_mr =<< attempt (pure current)
+
+runner2
+  :: ( MonadRescue m
+     , RaisesOnly  m errs
+     )
+  => m (a, w)
+  -> m (Either (OpenUnion errs) a, w)
+runner2 inner = do
+  (a, w)   <- inner
+  errOrVal <- attempt (pure a)
+  return (errOrVal, w)
+
+runner3
+  :: ( MonadRescue m
+     , RaisesOnly  m errs
+     )
+  => m (a, b, c)
+  -> m (Either (OpenUnion errs) a, b, c)
+runner3 inner = do
+  (a, s, w) <- inner
+  errOrVal  <- attempt (pure a)
+  return (errOrVal, s, w)
diff --git a/library/Control/Monad/Trans/Cleanup.hs b/library/Control/Monad/Trans/Cleanup.hs
new file mode 100644
--- /dev/null
+++ b/library/Control/Monad/Trans/Cleanup.hs
@@ -0,0 +1,4 @@
+module Control.Monad.Trans.Cleanup
+  (module Control.Monad.Trans.Cleanup.Types) where
+
+import           Control.Monad.Trans.Cleanup.Types
diff --git a/library/Control/Monad/Trans/Cleanup/Types.hs b/library/Control/Monad/Trans/Cleanup/Types.hs
new file mode 100644
--- /dev/null
+++ b/library/Control/Monad/Trans/Cleanup/Types.hs
@@ -0,0 +1,149 @@
+{-# LANGUAGE DataKinds            #-}
+{-# LANGUAGE LambdaCase           #-}
+{-# LANGUAGE ScopedTypeVariables  #-}
+{-# LANGUAGE TypeFamilies         #-}
+{-# LANGUAGE TypeOperators        #-}
+{-# LANGUAGE UndecidableInstances #-}
+
+-- | The 'CleanupT' transformer for adding async exceptions to a stack
+
+module Control.Monad.Trans.Cleanup.Types
+  ( CleanupT (..)
+  , CleanupIO
+  ) where
+
+import           Control.Applicative
+import           Control.Monad
+
+import           Control.Monad.Catch        as Catch
+import           Control.Monad.Cleanup
+import           Control.Monad.Fix
+import           Control.Monad.IO.Class
+import           Control.Monad.Trans.Class
+
+import           Data.Functor.Contravariant
+import           Data.WorldPeace
+
+-- | Adds 'SomeException' to an exception stack,
+--   and thus /aware/ of async exceptions
+newtype CleanupT m a = CleanupT { runCleanupT :: m a }
+
+type CleanupIO a = CleanupT IO a
+
+instance Eq (m a) => Eq (CleanupT m a) where
+  CleanupT a == CleanupT b = a == b
+
+instance Show (m a) => Show (CleanupT m a) where
+  show (CleanupT x) = "CleanupT (" <> show x <> ")"
+
+instance Functor m => Functor (CleanupT m) where
+  fmap f (CleanupT action) = CleanupT (fmap f action)
+
+instance Contravariant f => Contravariant (CleanupT f) where
+  contramap f = CleanupT . contramap f . runCleanupT
+
+instance Foldable t => Foldable (CleanupT t) where
+  foldMap f (CleanupT a) = foldMap f a
+  foldr f z (CleanupT a) = foldr f z a
+
+instance Traversable t => Traversable (CleanupT t) where
+  traverse f (CleanupT a) = CleanupT <$> traverse f a
+
+instance Applicative f => Applicative (CleanupT f) where
+  pure = CleanupT . pure
+  CleanupT f <*> CleanupT x = CleanupT (f <*> x)
+
+instance Alternative f => Alternative (CleanupT f) where
+  empty = CleanupT empty
+  CleanupT a <|> CleanupT b  = CleanupT (a <|> b)
+
+instance Monad m => Monad (CleanupT m) where
+  CleanupT x >>= f = CleanupT (runCleanupT . f =<< x)
+
+instance MonadTrans CleanupT where
+  lift = CleanupT
+
+instance MonadIO m => MonadIO (CleanupT m) where
+  liftIO = CleanupT . liftIO
+
+instance MonadPlus m => MonadPlus (CleanupT m) where
+  mzero = CleanupT mzero
+  mplus (CleanupT a) (CleanupT b) = CleanupT (mplus a b)
+
+instance MonadFix m => MonadFix (CleanupT m) where
+  mfix f = CleanupT (mfix (runCleanupT . f))
+
+instance MonadThrow m => MonadThrow (CleanupT m) where
+  throwM = CleanupT . throwM
+
+instance
+  ( Contains (Errors m) (Errors m)
+  , MonadRaise m
+  , MonadThrow m
+  )
+  => MonadRaise (CleanupT m) where
+  type Errors (CleanupT m) = SomeException ': Errors m
+
+  raise err = openUnion raiser throwM errsUnion
+    where
+      errsUnion :: OpenUnion (SomeException ': Errors m)
+      errsUnion = include err
+
+      raiser :: Contains err (Errors m) => OpenUnion err -> CleanupT m a
+      raiser = CleanupT . raise
+
+instance
+  ( Contains (Errors m) (Errors m)
+  , MonadCatch  m
+  , MonadRescue m
+  )
+  => MonadRescue (CleanupT m) where
+  attempt action =
+    Catch.try action >>= \case
+      Left  e@(SomeException _) -> return . Left $ include e
+      Right result              -> attempt $ pure result
+
+instance MonadCatch m => MonadCatch (CleanupT m) where
+  catch (CleanupT action) handler =
+    CleanupT $ catch action (runCleanupT . handler)
+
+instance MonadMask m => MonadMask (CleanupT m) where
+   mask action = CleanupT $ mask (\u -> runCleanupT (action $ q u))
+    where
+      q :: (m a -> m a) -> CleanupT m a -> CleanupT m a
+      q u = CleanupT . u . runCleanupT
+
+   uninterruptibleMask a =
+    CleanupT $ uninterruptibleMask (\u -> runCleanupT (a $ q u))
+      where
+        q :: (m a -> m a) -> CleanupT m a -> CleanupT m a
+        q u = CleanupT . u . runCleanupT
+
+   generalBracket acquire release use = CleanupT $
+     generalBracket
+       (runCleanupT acquire)
+       (\resource exitCase -> runCleanupT (release resource exitCase))
+       (runCleanupT . use)
+
+instance
+  ( Contains (Errors m) (Errors m)
+  , Contains (Errors m) (SomeException ': Errors m)
+  , MonadRescue m
+  , MonadMask   m
+  )
+  => MonadCleanup (CleanupT m) where
+  cleanup acquire onErr onOk action =
+    mask $ \restore -> do
+      resource <- acquire
+
+      attempt (restore $ action resource) >>= \case
+        Left errs -> do
+          _ <- uninterruptibleMask_ $
+                 fmap (\_ -> ()) (onErr resource errs)
+                   `catch` \(_ :: SomeException) -> return ()
+
+          raise errs
+
+        Right output -> do
+          _ <- onOk resource
+          return output
diff --git a/library/Control/Monad/Trans/Rescue.hs b/library/Control/Monad/Trans/Rescue.hs
new file mode 100644
--- /dev/null
+++ b/library/Control/Monad/Trans/Rescue.hs
@@ -0,0 +1,5 @@
+-- | This module supplies a "pure" monad transformer that
+--   can be used for adding 'MonadRescue' behaviour to a transformer stack
+module Control.Monad.Trans.Rescue (module Control.Monad.Trans.Rescue.Types) where
+
+import Control.Monad.Trans.Rescue.Types
diff --git a/library/Control/Monad/Trans/Rescue/Types.hs b/library/Control/Monad/Trans/Rescue/Types.hs
new file mode 100644
--- /dev/null
+++ b/library/Control/Monad/Trans/Rescue/Types.hs
@@ -0,0 +1,101 @@
+{-# LANGUAGE ApplicativeDo        #-}
+{-# LANGUAGE LambdaCase           #-}
+{-# LANGUAGE TypeFamilies         #-}
+{-# LANGUAGE UndecidableInstances #-}
+
+-- | The 'RescueT' transformer
+module Control.Monad.Trans.Rescue.Types
+  ( RescueT (..)
+  , Rescue
+  , runRescue
+  ) where
+
+import           Control.Monad.Catch
+import           Control.Monad.Cont
+import           Control.Monad.Fix
+import           Control.Monad.Rescue
+
+import           Data.Functor.Identity
+import           Data.WorldPeace
+
+-- | Add type-directed error handling abilities to a 'Monad'
+newtype RescueT errs m a
+  = RescueT { runRescueT :: m (Either (OpenUnion errs) a) }
+
+-- | A specialized version of 'RescueT' to be used without a transfromer stack
+type Rescue errs = RescueT errs Identity
+
+runRescue :: Rescue errs a -> Either (OpenUnion errs) a
+runRescue = runIdentity . runRescueT
+
+instance Eq (m (Either (OpenUnion errs) a)) => Eq (RescueT errs m a) where
+  RescueT a == RescueT b = a == b
+
+instance Show (m (Either (OpenUnion errs) a)) => Show (RescueT errs m a) where
+  show (RescueT inner) = "RescueT (" <> show inner <> ")"
+
+instance Functor m => Functor (RescueT errs m) where
+  fmap f (RescueT inner) = RescueT $ fmap (fmap f) inner
+
+instance Applicative m => Applicative (RescueT errs m) where
+  pure = RescueT . pure . pure
+  (RescueT fs) <*> (RescueT xs) = RescueT $ do
+    innerFs <- fs
+    innerXs <- xs
+    return (innerFs <*> innerXs)
+
+instance Monad m => Monad (RescueT errs m) where
+  RescueT action >>= k = RescueT $ action >>= \case
+    Left  err -> return (Left err)
+    Right val -> runRescueT (k val)
+
+instance MonadTrans (RescueT errs) where
+  lift action = RescueT (Right <$> action)
+
+instance MonadIO m => MonadIO (RescueT errs m) where
+  liftIO io = RescueT $ do
+    action <- liftIO io
+    return (Right action)
+
+instance MonadFix m => MonadFix (RescueT errs m) where
+  mfix f = RescueT . mfix $ \a ->
+    runRescueT . f $ case a of
+       Right r -> r
+       _       -> error "Empty mfix argument" -- absurd
+
+instance Foldable m => Foldable (RescueT errs m) where
+  foldMap f (RescueT m) = foldMap (foldMapEither f) m where
+    foldMapEither g (Right a) = g a
+    foldMapEither _ (Left _)  = mempty
+
+instance (Monad m, Traversable m) => Traversable (RescueT errs m) where
+  traverse f (RescueT m) = RescueT <$> traverse (traverseEither f) m
+    where
+      traverseEither g (Right val) = Right <$> g val
+      traverseEither _ (Left  err) = pure (Left err)
+
+instance Monad m => MonadRaise (RescueT errs m) where
+  type Errors (RescueT errs m) = errs
+  raise err = RescueT . pure $ raise err
+
+instance Monad m => MonadRescue (RescueT errs m) where
+  attempt (RescueT action) = RescueT (Right <$> action)
+
+instance
+  ( IsMember SomeException errs
+  , Monad m
+  )
+  => MonadThrow (RescueT errs m) where
+  throwM = RescueT . pure . Left . openUnionLift . toException
+
+instance
+  ( IsMember SomeException errs
+  , Contains errs errs
+  , Monad m
+  )
+  => MonadCatch (RescueT errs m) where
+  catch action handler =
+    rescue action $ \errs ->
+      case openUnionMatch errs of
+        Nothing  -> raise errs
+        Just err -> maybe (raise err) handler $ fromException err
diff --git a/library/Data/Exception/Types.hs b/library/Data/Exception/Types.hs
new file mode 100644
--- /dev/null
+++ b/library/Data/Exception/Types.hs
@@ -0,0 +1,45 @@
+-- | Common exceptions
+module Data.Exception.Types
+  ( NotFound      (..)
+  , NotAllowed    (..)
+  , AlreadyExists (..)
+  , OutOfBounds   (..)
+  , DivideByZero  (..)
+  ) where
+
+import           Data.Text
+
+data NotFound entity
+  = NotFound
+  deriving (Show, Eq)
+
+data NotAllowed entity user
+  = NotAllowed entity user
+  deriving (Show, Eq)
+
+newtype AlreadyExists entity
+  = AlreadyExists entity
+  deriving (Show, Eq)
+
+newtype OutOfBounds entity index
+  = OutOfBounds index
+  deriving (Show, Eq)
+
+data DivideByZero
+  = DivideByZero
+  deriving (Show, Eq)
+
+newtype InvalidFormat entity
+  = InvalidFormat entity
+  deriving (Show, Eq)
+
+-- | Attach a message to an exception, typicaly for runtime user feedback
+--
+-- ==== __Examples__
+--
+-- >>> :set -XOverloadedStrings
+-- >>> show $ InvalidFormat "foo" `WithMessage` "Not a valid JSON object"
+-- "InvalidFormat \"foo\" `WithMessage` \"Not a valid JSON object\""
+data WithMessage err
+  = err `WithMessage` Text
+  deriving (Show, Eq)
diff --git a/library/Data/Result.hs b/library/Data/Result.hs
new file mode 100644
--- /dev/null
+++ b/library/Data/Result.hs
@@ -0,0 +1,18 @@
+{-# LANGUAGE FlexibleContexts #-}
+{-# LANGUAGE TypeFamilies     #-}
+
+module Data.Result
+  ( fromEither
+  -- * Reexports
+  , module Data.Result.Types
+  ) where
+
+import           Data.Result.Types
+import           Data.WorldPeace
+
+import           Control.Monad.Raise
+
+-- | Upgrade from an 'Either' to a 'Result'
+fromEither :: Subset err (OpenUnion errs) => Either err val -> Result errs val
+fromEither (Right val) = Ok val
+fromEither (Left  err) = Err (include err)
diff --git a/library/Data/Result/Types.hs b/library/Data/Result/Types.hs
new file mode 100644
--- /dev/null
+++ b/library/Data/Result/Types.hs
@@ -0,0 +1,21 @@
+{-# LANGUAGE DataKinds       #-}
+{-# LANGUAGE KindSignatures  #-}
+{-# LANGUAGE PatternSynonyms #-}
+
+module Data.Result.Types
+  ( Result
+  , pattern Ok
+  , pattern Err
+  ) where
+
+import           Data.Kind
+import           Data.WorldPeace
+
+-- | 'Result' is a synonym for 'Either (OpenUnion errs) a'
+type Result (errs :: [Type]) = Either (OpenUnion errs)
+
+pattern Ok :: val -> Either (OpenUnion err) val
+pattern Ok val = Right val
+
+pattern Err :: OpenUnion errs -> Either (OpenUnion errs) b
+pattern Err errs = Left errs
diff --git a/library/Data/WorldPeace/IsOpenUnion/Family.hs b/library/Data/WorldPeace/IsOpenUnion/Family.hs
new file mode 100644
--- /dev/null
+++ b/library/Data/WorldPeace/IsOpenUnion/Family.hs
@@ -0,0 +1,12 @@
+{-# LANGUAGE DataKinds    #-}
+{-# LANGUAGE TypeFamilies #-}
+
+module Data.WorldPeace.IsOpenUnion.Family (IsOpenUnion) where
+
+import           Data.WorldPeace
+
+-- | Type-level check that a type is an open union.
+--   For use with the @Subset'@ typeclass.
+type family (IsOpenUnion a) :: Bool where
+  IsOpenUnion (OpenUnion a) = 'True
+  IsOpenUnion a             = 'False
diff --git a/library/Data/WorldPeace/Subset/Class.hs b/library/Data/WorldPeace/Subset/Class.hs
new file mode 100644
--- /dev/null
+++ b/library/Data/WorldPeace/Subset/Class.hs
@@ -0,0 +1,25 @@
+{-# LANGUAGE FlexibleInstances     #-}
+{-# LANGUAGE MultiParamTypeClasses #-}
+{-# LANGUAGE ScopedTypeVariables   #-}
+{-# LANGUAGE TypeApplications      #-}
+{-# LANGUAGE TypeFamilies          #-}
+{-# LANGUAGE UndecidableInstances  #-}
+
+module Data.WorldPeace.Subset.Class (Subset (..)) where
+
+import           Data.Proxy
+import           Data.WorldPeace
+import           Data.WorldPeace.IsOpenUnion.Family
+import           Data.WorldPeace.Subset.Class.Internal
+
+-- | State that some type @err@ is a subset of @errs@
+--
+--   In essence, this is used to avoid having to specially lift
+--   bare values to an 'OpenUnion'. We can treat all types
+--   and 'OpenUnion's the same.
+class Subset err errs where
+  include :: err -> errs
+
+instance (IsOpenUnion err ~ flag, Subset' flag err errs) => Subset err (OpenUnion errs) where
+  include = include' (Proxy @flag)
+  {-# INLINE include #-}
diff --git a/library/Data/WorldPeace/Subset/Class/Internal.hs b/library/Data/WorldPeace/Subset/Class/Internal.hs
new file mode 100644
--- /dev/null
+++ b/library/Data/WorldPeace/Subset/Class/Internal.hs
@@ -0,0 +1,22 @@
+{-# LANGUAGE DataKinds             #-}
+{-# LANGUAGE FlexibleInstances     #-}
+{-# LANGUAGE KindSignatures        #-}
+{-# LANGUAGE MultiParamTypeClasses #-}
+{-# LANGUAGE UndecidableInstances  #-}
+
+module Data.WorldPeace.Subset.Class.Internal (Subset' (..)) where
+
+import           Data.Kind
+import           Data.Proxy
+import           Data.WorldPeace
+
+-- | Hack around overlapping instances to check subsets
+--   of bare values or 'OpenUnion's automatically
+class Subset' (flag :: Bool) (err :: Type) (errs :: [Type]) where
+  include' :: Proxy flag -> err -> OpenUnion errs
+
+instance Contains err errs => Subset' 'True (OpenUnion err) errs where
+  include' _ = relaxOpenUnion
+
+instance IsMember err errs => Subset' 'False err errs where
+  include' _ = openUnionLift
diff --git a/lint/Main.hs b/lint/Main.hs
new file mode 100644
--- /dev/null
+++ b/lint/Main.hs
@@ -0,0 +1,19 @@
+module Main (main) where
+
+import Language.Haskell.HLint (hlint)
+import System.Exit
+
+arguments :: [String]
+arguments =
+    [ "benchmark"
+    , "library"
+    , "test"
+    , "doctest"
+    ]
+
+main :: IO ()
+main = do
+  hints <- hlint arguments
+  if null hints
+    then exitSuccess
+    else exitFailure
diff --git a/rescue.cabal b/rescue.cabal
new file mode 100644
--- /dev/null
+++ b/rescue.cabal
@@ -0,0 +1,175 @@
+cabal-version: 1.12
+
+-- This file has been generated from package.yaml by hpack version 0.33.0.
+--
+-- see: https://github.com/sol/hpack
+--
+-- hash: 70b533d152069a3c11b8c763cbf6104c93c199d3858df8f49c4564331744b375
+
+name:           rescue
+version:        0.2.0
+synopsis:       More understandable exceptions
+description:    An error handling library focused on clarity and control
+category:       Error Handling
+homepage:       https://github.com/expede/rescue#readme
+bug-reports:    https://github.com/expede/rescue/issues
+author:         Brooklyn Zelenka
+maintainer:     hello@brooklynzelenka.com
+copyright:      © 2020 Brooklyn Zelenka
+license:        Apache-2.0
+license-file:   LICENSE
+tested-with:    GHC==8.8.3
+build-type:     Simple
+extra-source-files:
+    README.md
+
+source-repository head
+  type: git
+  location: https://github.com/expede/rescue
+
+library
+  exposed-modules:
+      Control.Monad.Cleanup
+      Control.Monad.Cleanup.Class
+      Control.Monad.Raise
+      Control.Monad.Raise.Class
+      Control.Monad.Raise.Constraint
+      Control.Monad.Rescue
+      Control.Monad.Rescue.Class
+      Control.Monad.Trans.Cleanup
+      Control.Monad.Trans.Cleanup.Types
+      Control.Monad.Trans.Rescue
+      Control.Monad.Trans.Rescue.Types
+      Data.Exception.Types
+      Data.Result
+      Data.Result.Types
+      Data.WorldPeace.IsOpenUnion.Family
+      Data.WorldPeace.Subset.Class
+      Data.WorldPeace.Subset.Class.Internal
+  other-modules:
+      Paths_rescue
+  hs-source-dirs:
+      library
+  ghc-options: -Wall -Wcompat -Widentities -Wincomplete-record-updates -Wincomplete-uni-patterns -Wmissing-export-lists -Wpartial-fields -Wredundant-constraints -fhide-source-paths
+  build-depends:
+      base <5
+    , exceptions
+    , ghc
+    , mtl
+    , text
+    , transformers
+    , world-peace
+  default-language: Haskell2010
+
+test-suite rescue-doctest
+  type: exitcode-stdio-1.0
+  main-is: Main.hs
+  other-modules:
+      Paths_rescue
+  hs-source-dirs:
+      doctest
+  ghc-options: -Wall -Wcompat -Widentities -Wincomplete-record-updates -Wincomplete-uni-patterns -Wmissing-export-lists -Wpartial-fields -Wredundant-constraints -fhide-source-paths -threaded -rtsopts -with-rtsopts=-N
+  build-depends:
+      Glob
+    , QuickCheck
+    , base <5
+    , directory
+    , directory-tree
+    , doctest
+    , exceptions
+    , ghc
+    , lens-aeson
+    , mtl
+    , quickcheck-instances
+    , text
+    , transformers
+    , world-peace
+    , yaml
+  default-language: Haskell2010
+
+test-suite rescue-lint
+  type: exitcode-stdio-1.0
+  main-is: Main.hs
+  other-modules:
+      Paths_rescue
+  hs-source-dirs:
+      lint
+  ghc-options: -Wall -Wcompat -Widentities -Wincomplete-record-updates -Wincomplete-uni-patterns -Wmissing-export-lists -Wpartial-fields -Wredundant-constraints -fhide-source-paths
+  build-depends:
+      base
+    , exceptions
+    , ghc
+    , hlint
+    , mtl
+    , rio
+    , text
+    , transformers
+    , world-peace
+  default-language: Haskell2010
+
+test-suite rescue-test
+  type: exitcode-stdio-1.0
+  main-is: Main.hs
+  other-modules:
+      Control.Monad.Cleanup
+      Control.Monad.Cleanup.Class
+      Control.Monad.Raise
+      Control.Monad.Raise.Class
+      Control.Monad.Raise.Constraint
+      Control.Monad.Rescue
+      Control.Monad.Rescue.Class
+      Control.Monad.Trans.Cleanup
+      Control.Monad.Trans.Cleanup.Types
+      Control.Monad.Trans.Rescue
+      Control.Monad.Trans.Rescue.Types
+      Data.Exception.Types
+      Data.Result
+      Data.Result.Types
+      Data.WorldPeace.IsOpenUnion.Family
+      Data.WorldPeace.Subset.Class
+      Data.WorldPeace.Subset.Class.Internal
+      Paths_rescue
+  hs-source-dirs:
+      library
+      test
+  ghc-options: -Wall -Wcompat -Widentities -Wincomplete-record-updates -Wincomplete-uni-patterns -Wmissing-export-lists -Wpartial-fields -Wredundant-constraints -fhide-source-paths -threaded -rtsopts -with-rtsopts=-N
+  build-depends:
+      QuickCheck
+    , base <5
+    , exceptions
+    , ghc
+    , hspec
+    , hspec-core
+    , hspec-expectations
+    , mtl
+    , quickcheck-instances
+    , rescue
+    , tasty
+    , tasty-hspec
+    , tasty-hunit
+    , tasty-rerun
+    , tasty-smallcheck
+    , text
+    , transformers
+    , world-peace
+  default-language: Haskell2010
+
+benchmark rescue-benchmark
+  type: exitcode-stdio-1.0
+  main-is: Main.hs
+  other-modules:
+      Paths_rescue
+  hs-source-dirs:
+      benchmark
+  ghc-options: -Wall -Wcompat -Widentities -Wincomplete-record-updates -Wincomplete-uni-patterns -Wmissing-export-lists -Wpartial-fields -Wredundant-constraints -fhide-source-paths -threaded -rtsopts -with-rtsopts=-N -O2
+  build-depends:
+      base <5
+    , criterion
+    , exceptions
+    , ghc
+    , mtl
+    , rescue
+    , text
+    , transformers
+    , world-peace
+  default-language: Haskell2010
diff --git a/test/Main.hs b/test/Main.hs
new file mode 100644
--- /dev/null
+++ b/test/Main.hs
@@ -0,0 +1,9 @@
+module Main (main) where
+
+-- import Test.Tasty
+
+main :: IO ()
+main = pure () -- defaultMain =<< tests
+
+-- tests :: IO TestTree
+-- tests = pure []