diff --git a/LICENSE b/LICENSE
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--- /dev/null
+++ b/LICENSE
@@ -0,0 +1,11 @@
+Copyright 2019-2020 Markus Schirp
+
+Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:
+
+1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
+
+2. 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.
+
+3. Neither the name of the copyright holder nor the names of its 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 HOLDER 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
@@ -0,0 +1,6 @@
+![CI](https://github.com/mbj/devtools-hs/workflows/CI/badge.svg)
+
+# devtools
+
+Experimental. Haskell development tooling.
+This project tries to deduplicate setup of development tools.
diff --git a/app/Main.hs b/app/Main.hs
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--- /dev/null
+++ b/app/Main.hs
@@ -0,0 +1,8 @@
+module Main (main) where
+
+import System.IO (IO)
+
+import qualified Devtools
+
+main :: IO ()
+main = Devtools.main Devtools.defaultConfig
diff --git a/devtools.cabal b/devtools.cabal
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--- /dev/null
+++ b/devtools.cabal
@@ -0,0 +1,116 @@
+cabal-version: 1.18
+
+-- This file has been generated from package.yaml by hpack version 0.33.0.
+--
+-- see: https://github.com/sol/hpack
+--
+-- hash: 28f0b2dd9ab8fad70261ddc0bc6fc074f72800cb12ac29b00e9055bdd91c4bd1
+
+name:           devtools
+version:        0.0.1
+synopsis:       Haskell development tool agregate
+description:    An attempt to group development that would typically run on CI / local
+                into one tasty interface.
+category:       Testing
+homepage:       https://github.com/mbj/devtools-hs#readme
+bug-reports:    https://github.com/mbj/devtools-hs/issues
+author:         Markus Schirp <mbj@schirp-dso.com>
+maintainer:     Markus Schirp <mbj@schirp-dso.com>
+license:        BSD3
+license-file:   LICENSE
+build-type:     Simple
+extra-doc-files:
+    README.md
+
+source-repository head
+  type: git
+  location: https://github.com/mbj/devtools-hs
+
+flag development
+  description: Run GHC with development flags
+  manual: True
+  default: False
+
+library
+  exposed-modules:
+      Devtools
+      Devtools.Dependencies
+      Devtools.HLint
+      Devtools.Prelude
+  other-modules:
+      Paths_devtools
+  hs-source-dirs:
+      src
+  default-extensions: DerivingStrategies LambdaCase NoImplicitPrelude OverloadedStrings RecordWildCards StrictData
+  ghc-options: -Wall -Wcompat -Widentities -Wimplicit-prelude -Wincomplete-record-updates -Wincomplete-uni-patterns -Wmissing-exported-signatures -Wmissing-local-signatures -Wmonomorphism-restriction -Wredundant-constraints -fplugin=SourceConstraints -funbox-strict-fields -optP-Wno-nonportable-include-path
+  build-depends:
+      Diff >0.3 && <0.5
+    , base >4.12 && <4.14
+    , bytestring >=0.10 && <0.11
+    , cmdargs >=0.10.20 && <0.11
+    , filepath >=1.4 && <1.5
+    , hlint >2.1 && <3
+    , mprelude >=0.1.0 && <0.2
+    , source-constraints >=0.0.1 && <0.1
+    , tasty >=1.3.1 && <1.4
+    , tasty-mgolden >=0.0.1 && <0.1
+    , text >=1.2 && <1.3
+    , typed-process >=0.2 && <0.3
+  if flag(development)
+    ghc-options: -Werror
+  else
+    ghc-options: -Wwarn
+  default-language: Haskell2010
+
+executable devtools
+  main-is: app/Main.hs
+  other-modules:
+      Paths_devtools
+  default-extensions: DerivingStrategies LambdaCase NoImplicitPrelude OverloadedStrings RecordWildCards StrictData
+  ghc-options: -Wall -Wcompat -Widentities -Wimplicit-prelude -Wincomplete-record-updates -Wincomplete-uni-patterns -Wmissing-exported-signatures -Wmissing-local-signatures -Wmonomorphism-restriction -Wredundant-constraints -fplugin=SourceConstraints -funbox-strict-fields -optP-Wno-nonportable-include-path -rtsopts -threaded -with-rtsopts=-N
+  build-depends:
+      Diff >0.3 && <0.5
+    , base >4.12 && <4.14
+    , bytestring >=0.10 && <0.11
+    , cmdargs >=0.10.20 && <0.11
+    , devtools
+    , filepath >=1.4 && <1.5
+    , hlint >2.1 && <3
+    , mprelude >=0.1.0 && <0.2
+    , source-constraints >=0.0.1 && <0.1
+    , tasty >=1.3.1 && <1.4
+    , tasty-mgolden >=0.0.1 && <0.1
+    , text >=1.2 && <1.3
+    , typed-process >=0.2 && <0.3
+  if flag(development)
+    ghc-options: -Werror
+  else
+    ghc-options: -Wwarn
+  default-language: Haskell2010
+
+test-suite devtools-test
+  type: exitcode-stdio-1.0
+  main-is: app/Main.hs
+  other-modules:
+      Paths_devtools
+  default-extensions: DerivingStrategies LambdaCase NoImplicitPrelude OverloadedStrings RecordWildCards StrictData
+  ghc-options: -Wall -Wcompat -Widentities -Wimplicit-prelude -Wincomplete-record-updates -Wincomplete-uni-patterns -Wmissing-exported-signatures -Wmissing-local-signatures -Wmonomorphism-restriction -Wredundant-constraints -fplugin=SourceConstraints -funbox-strict-fields -optP-Wno-nonportable-include-path -rtsopts -threaded -with-rtsopts=-N
+  build-depends:
+      Diff >0.3 && <0.5
+    , base >4.12 && <4.14
+    , bytestring >=0.10 && <0.11
+    , cmdargs >=0.10.20 && <0.11
+    , devtools
+    , filepath >=1.4 && <1.5
+    , hlint >2.1 && <3
+    , mprelude >=0.1.0 && <0.2
+    , source-constraints >=0.0.1 && <0.1
+    , tasty >=1.3.1 && <1.4
+    , tasty-mgolden >=0.0.1 && <0.1
+    , text >=1.2 && <1.3
+    , typed-process >=0.2 && <0.3
+  if flag(development)
+    ghc-options: -Werror
+  else
+    ghc-options: -Wwarn
+  default-language: Haskell2010
diff --git a/src/Devtools.hs b/src/Devtools.hs
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--- /dev/null
+++ b/src/Devtools.hs
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+module Devtools (Config(..), defaultConfig, defaultMain, main, testTree) where
+
+import Devtools.Prelude
+import System.IO (putStrLn)
+
+import qualified Devtools.Dependencies as Dependencies
+import qualified Devtools.HLint        as HLint
+import qualified Test.Tasty            as Tasty
+
+newtype Config = Config
+  { hlintArguments :: [String]
+  }
+
+defaultConfig :: Config
+defaultConfig = Config
+  { hlintArguments = []
+  }
+
+defaultMain :: IO ()
+defaultMain = main defaultConfig
+
+main :: Config -> IO ()
+main config = do
+  putStrLn empty
+  Tasty.defaultMain $ testTree config
+
+testTree :: Config -> Tasty.TestTree
+testTree Config{..} = Tasty.testGroup "devtools"
+  [ Dependencies.testTree
+  , HLint.testTree hlintArguments
+  ]
diff --git a/src/Devtools/Dependencies.hs b/src/Devtools/Dependencies.hs
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--- /dev/null
+++ b/src/Devtools/Dependencies.hs
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+module Devtools.Dependencies (testTree) where
+
+import Data.Tuple (fst)
+import Devtools.Prelude
+
+import qualified Data.ByteString.Lazy  as LBS
+import qualified Data.Text.Encoding    as Text
+import qualified System.Process.Typed  as Process
+import qualified Test.Tasty            as Tasty
+import qualified Test.Tasty.MGolden    as Tasty
+
+testTree :: Tasty.TestTree
+testTree =
+  Tasty.goldenTest
+    "dependencies"
+    "test/stack-dependencies.txt"
+    readDependenciesText
+  where
+    readDependenciesText :: IO Text
+    readDependenciesText
+      = Text.decodeUtf8 . LBS.toStrict <$> readDependencies
+
+    readDependencies :: IO LBS.ByteString
+    readDependencies
+      = fst <$> Process.readProcess_ (Process.proc "stack" ["ls", "dependencies", "--test"])
diff --git a/src/Devtools/HLint.hs b/src/Devtools/HLint.hs
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--- /dev/null
+++ b/src/Devtools/HLint.hs
@@ -0,0 +1,47 @@
+module Devtools.HLint (testTree) where
+
+import Control.Applicative (empty, pure)
+import Data.Function (($), (.), const)
+import Data.Functor (void)
+import Data.Semigroup ((<>))
+import Data.String (String)
+import Data.Typeable (Typeable)
+import System.IO
+
+import qualified Data.Foldable                      as Foldable
+import qualified Language.Haskell.HLint4            as HLint
+import qualified System.Console.CmdArgs.Verbosity   as CmdArgs
+import qualified Test.Tasty                         as Tasty
+import qualified Test.Tasty.Providers               as Tasty
+import qualified Test.Tasty.Providers.ConsoleFormat as Tasty
+
+newtype HLintTest = HLintTest [String]
+  deriving stock Typeable
+
+instance Tasty.IsTest HLintTest where
+  run _options (HLintTest arguments) _callback = runHLintTest arguments
+  testOptions = pure empty
+
+testTree :: [String] -> Tasty.TestTree
+testTree = Tasty.singleTest "hlint" . HLintTest
+
+runHLintTest :: [String] -> IO Tasty.Result
+runHLintTest arguments = do
+  ideas <- HLint.hlint $ ["--quiet"] <> arguments <> ["."]
+
+  pure $ if Foldable.null ideas
+    then Tasty.testPassed empty
+    else Tasty.testFailedDetails empty
+      . Tasty.ResultDetailsPrinter
+      . const
+      . const
+      $ runHLintVerbose arguments
+
+-- Run HLint (again) but with output enabled.
+-- There is no good public API in HLint to render the output.
+runHLintVerbose :: [String] -> IO ()
+runHLintVerbose arguments = do
+  -- CmdArgs the CLI parsing lib for hlint leaks global state.
+  -- We have to reset it here.
+  CmdArgs.setVerbosity CmdArgs.Normal
+  void . HLint.hlint $ arguments <> ["--", "."]
diff --git a/src/Devtools/Prelude.hs b/src/Devtools/Prelude.hs
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--- /dev/null
+++ b/src/Devtools/Prelude.hs
@@ -0,0 +1,3 @@
+module Devtools.Prelude (module Exports) where
+
+import MPrelude as Exports
