diff --git a/LICENSE b/LICENSE
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--- /dev/null
+++ b/LICENSE
@@ -0,0 +1,30 @@
+Copyright Alex Mingoia (c) 2022
+
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+    * Redistributions of source code must retain the above copyright
+      notice, this list of conditions and the following disclaimer.
+
+    * Redistributions in binary form must reproduce the above
+      copyright notice, this list of conditions and the following
+      disclaimer in the documentation and/or other materials provided
+      with the distribution.
+
+    * Neither the name of Alex Mingoia nor the names of other
+      contributors may be used to endorse or promote products derived
+      from this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
diff --git a/README.md b/README.md
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--- /dev/null
+++ b/README.md
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+# wai-env
+
+[![Hackage](https://img.shields.io/hackage/v/wai-env.svg?style=flat)](http://hackage.haskell.org/package/wai-env)
+![BSD3 License](http://img.shields.io/badge/license-BSD3-brightgreen.svg)
+
+WAI middleware to parameterize requests with an environment, and retrieve the environment from a request.
diff --git a/Setup.hs b/Setup.hs
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--- /dev/null
+++ b/Setup.hs
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+import Distribution.Simple
+main = defaultMain
diff --git a/src/Network/Wai/Middleware/Environment.hs b/src/Network/Wai/Middleware/Environment.hs
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--- /dev/null
+++ b/src/Network/Wai/Middleware/Environment.hs
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+module Network.Wai.Middleware.Environment
+  ( withEnvironment,
+    environment,
+  )
+where
+
+import Data.Default (Default, def)
+import Data.Maybe (fromMaybe)
+import qualified Data.Vault.Lazy as V
+import Network.Wai (Middleware, Request (..))
+import System.IO.Unsafe (unsafePerformIO)
+
+vaultKey :: Default a => V.Key a
+vaultKey = unsafePerformIO V.newKey
+{-# NOINLINE vaultKey #-}
+
+-- | Parametize subsequent requests with environment.
+withEnvironment :: Default a => a -> Middleware
+withEnvironment env app req respond = do
+  let req' = req {vault = V.insert vaultKey env (vault req)}
+  app req' respond
+
+-- | Retrieve request environment.
+environment :: Default a => Request -> a
+environment = fromMaybe def . V.lookup vaultKey . vault
diff --git a/wai-env.cabal b/wai-env.cabal
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--- /dev/null
+++ b/wai-env.cabal
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+name:                wai-env
+version:             1.0.0.0
+synopsis:						 WAI middleware to parameterize requests with environment. 
+description:				 WAI middleware to parameterize requests with environment, and retrieve environment from requests.
+homepage:            https://github.com/alexmingoia/wai-env#readme
+license:             BSD3
+license-file:        LICENSE
+author:              Alex Mingoia
+maintainer:          alex@alexmingoia.com
+copyright:           2021 Alexander C. Mingoia
+category:            Web
+build-type:          Simple
+extra-source-files:  README.md
+cabal-version:       >=1.10
+
+library
+  hs-source-dirs:      src
+  exposed-modules:     Network.Wai.Middleware.Environment
+  build-depends:
+      base >=4.7 && <5
+    , data-default >=0.7 && <0.8
+    , vault ==0.3.*
+    , wai >=3.0 && <3.3
+  default-language:    Haskell2010
+
+source-repository head
+  type:     git
+  location: https://github.com/alexmingoia/wai-env