diff --git a/LICENSE b/LICENSE
new file mode 100644
--- /dev/null
+++ b/LICENSE
@@ -0,0 +1,30 @@
+Copyright (c) 2013, Ricky Elrod
+
+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 Ricky Elrod 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/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/cruncher-types.cabal b/cruncher-types.cabal
new file mode 100644
--- /dev/null
+++ b/cruncher-types.cabal
@@ -0,0 +1,45 @@
+name:                cruncher-types
+version:             1.0.0
+synopsis:            Request and Response types for Eval.so's API
+description:
+  You are not likely to find this useful unless you are building a library for
+  accessing Eval.so's new API, or working on the "Cruncher" backend.
+homepage:            http://github.com/eval-so/cruncher-types
+license:             BSD3
+license-file:        LICENSE
+author:              Ricky Elrod
+maintainer:          ricky@elrod.me
+copyright:           2013 - Ricky Elrod
+category:            Eval.so
+build-type:          Simple
+cabal-version:       >=1.18
+
+library
+  exposed-modules:
+    Evalso.Cruncher.FinalResult
+    Evalso.Cruncher.SandboxResult
+    Evalso.Cruncher.Request
+
+  ghc-options: -Wall -O2
+  hs-source-dirs: src
+  default-language:    Haskell2010
+
+  build-depends:
+      base ==4.6.*
+    , bytestring ==0.10.*
+    , containers ==0.5.*
+    , text ==0.11.*
+    , aeson ==0.6.*
+
+test-suite hlint
+  hs-source-dirs: tests
+  main-is: hlint.hs
+  type: exitcode-stdio-1.0
+  ghc-options: -Wall -threaded -rtsopts -with-rtsopts=-N
+  build-depends:
+      base
+    , hlint >= 1.7
+
+source-repository head
+  type:     git
+  location: git://github.com/eval-so/cruncher-types.git
diff --git a/src/Evalso/Cruncher/FinalResult.hs b/src/Evalso/Cruncher/FinalResult.hs
new file mode 100644
--- /dev/null
+++ b/src/Evalso/Cruncher/FinalResult.hs
@@ -0,0 +1,63 @@
+{-# LANGUAGE OverloadedStrings, Trustworthy #-}
+-- |
+-- Maintainer  : Ricky Elrod <ricky@elrod.me>
+-- Stability   : stable
+--
+-- The highest level of a response that Cruncher deals with. Contains only the
+-- final result of a sandbox run, including compilation, execution, and output
+-- files (which are base64-encoded).
+
+module Evalso.Cruncher.FinalResult (FinalResult (..)) where
+
+import Evalso.Cruncher.SandboxResult
+
+import Control.Applicative
+import Control.Monad (mzero)
+import Data.Aeson
+import Data.ByteString (ByteString)
+import Data.Map (Map)
+
+-- | The final result for a given request.
+--
+--   This contains the 'Result' obtained from both evaluation and compilation
+--   as well as any files which resulted from performing the above steps.
+--   Such files should placed in @~/output/@ of the evaluation.
+--
+--   This data type also handles error handling, in the form of types.
+data FinalResult
+  = FinalResult
+    {
+      compile     :: Maybe SandboxResult -- ^ The compilation result, if any
+    , run         :: Maybe SandboxResult -- ^ The execution result, if any
+    , outputFiles :: Map String ByteString -- ^ Base64-encoded output files
+    }
+  | NoSuchLanguage
+  | SELinuxNotEnforcing
+  deriving (Eq, Show)
+
+instance ToJSON FinalResult where
+  toJSON (FinalResult compile' run' outputFiles') = object
+    [
+      "compile"     .= compile'
+    , "run"         .= run'
+    , "outputFiles" .= outputFiles'
+    ]
+
+  -- | TODO: i18n
+  toJSON (NoSuchLanguage) = object ["error" .= noSuchLanguageError]
+    where
+      noSuchLanguageError :: String
+      noSuchLanguageError = "We do not currently support that language"
+
+  -- | TODO: i18n
+  toJSON (SELinuxNotEnforcing) = object ["error" .= selinuxError]
+    where
+      selinuxError :: String
+      selinuxError = "Internal security error - halting request"
+
+instance FromJSON FinalResult where
+  parseJSON (Object v) = FinalResult <$>
+                             v .: "compile"
+                         <*> v .: "run"
+                         <*> v .: "outputFiles"
+  parseJSON _          = mzero
diff --git a/src/Evalso/Cruncher/Request.hs b/src/Evalso/Cruncher/Request.hs
new file mode 100644
--- /dev/null
+++ b/src/Evalso/Cruncher/Request.hs
@@ -0,0 +1,34 @@
+{-# LANGUAGE OverloadedStrings, Trustworthy #-}
+-- |
+-- Maintainer  : Ricky Elrod <ricky@elrod.me>
+-- Stability   : stable
+--
+-- Handles incoming requests (usually from our Yesod frontend, but could be
+-- from anywhere).
+
+module Evalso.Cruncher.Request (Request (..)) where
+
+import Control.Applicative
+import Control.Monad (mzero)
+import Data.Aeson hiding (Result)
+import qualified Data.ByteString.Char8 as C8
+import qualified Data.Text as T
+
+-- | Describes an incoming request to the system. Proper use of this will
+--   normally lead to some kind of a 'IO' 'Result'.
+data Request = Request {
+    language    :: String
+  , code        :: T.Text
+  , files       :: Maybe [(String, C8.ByteString)]
+  , compileOnly :: Bool
+  , stdin       :: Maybe T.Text
+} deriving (Eq, Show)
+
+instance FromJSON Request where
+  parseJSON (Object v) = Request <$>
+                             v .:  "language"
+                         <*> v .:  "code"
+                         <*> v .:? "inputFiles"
+                         <*> v .:? "compilationOnly" .!= False
+                         <*> v .:? "stdin"
+  parseJSON _          = mzero
diff --git a/src/Evalso/Cruncher/SandboxResult.hs b/src/Evalso/Cruncher/SandboxResult.hs
new file mode 100644
--- /dev/null
+++ b/src/Evalso/Cruncher/SandboxResult.hs
@@ -0,0 +1,42 @@
+{-# LANGUAGE OverloadedStrings, Trustworthy #-}
+-- |
+-- Maintainer  : Ricky Elrod <ricky@elrod.me>
+-- Stability   : stable
+--
+-- Contains data types/constructors for individual sandbox runs.
+-- For example, the compile step will produce a 'SandboxResult', which is
+-- defined in this module. The execution/evaluation step will also produce a
+-- 'SandboxResult'.
+
+module Evalso.Cruncher.SandboxResult (SandboxResult (..)) where
+
+import Control.Applicative
+import Control.Monad (mzero)
+import Data.Aeson hiding (Result)
+import Data.Text (Text)
+
+-- | Describes the result we get back after performing an evaluation (or
+--   compilation). This is almost always wrapped in 'IO'.
+data SandboxResult = SandboxResult {
+    stdout   :: Text
+  , stderr   :: Text
+  , wallTime :: Int
+  , exitCode :: Int
+} deriving (Eq, Show)
+
+instance ToJSON SandboxResult where
+  toJSON (SandboxResult stdout' stderr' wallTime' exitCode') = object
+    [
+      "stdout"   .= stdout'
+    , "stderr"   .= stderr'
+    , "wallTime" .= wallTime'
+    , "exitCode" .= exitCode'
+    ]
+
+instance FromJSON SandboxResult where
+  parseJSON (Object v) = SandboxResult <$>
+                             v .: "stdout"
+                         <*> v .: "stderr"
+                         <*> v .: "wallTime"
+                         <*> v .: "exitCode"
+  parseJSON _          = mzero
diff --git a/tests/hlint.hs b/tests/hlint.hs
new file mode 100644
--- /dev/null
+++ b/tests/hlint.hs
@@ -0,0 +1,12 @@
+module Main where
+
+import Control.Monad
+import Language.Haskell.HLint
+import System.Environment
+import System.Exit
+
+main :: IO ()
+main = do
+  args <- getArgs
+  hints <- hlint $ ["src", "--cpp-define=HLINT", "--cpp-ansi"] ++ args
+  unless (null hints) exitFailure