diff --git a/LICENSE b/LICENSE
new file mode 100644
--- /dev/null
+++ b/LICENSE
@@ -0,0 +1,191 @@
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diff --git a/Laborantin.hs b/Laborantin.hs
new file mode 100644
--- /dev/null
+++ b/Laborantin.hs
@@ -0,0 +1,40 @@
+
+module Laborantin where
+
+import Laborantin.Types
+import Laborantin.DSL
+import Laborantin.Implementation
+import Control.Monad.IO.Class
+import Control.Monad.Reader
+import Control.Monad.Error
+import qualified Data.Set as S
+
+execute :: (MonadIO m) => Backend m -> ScenarioDescription m -> ParameterSet -> m ()
+execute b sc prm = execution
+  where execution = do
+            (exec,final) <- bPrepareExecution b sc prm 
+            status <- runReaderT (runErrorT (go exec `catchError` recover exec)) (b, exec)
+            let exec' = either (\_ -> exec {eStatus = Failure}) (\_ -> exec {eStatus = Success}) status
+            bFinalizeExecution b exec' final
+            where go exec = do 
+                        bSetup b exec
+                        bRun b exec
+                        bTeardown b exec
+                        bAnalyze b exec
+                  recover exec err = bRecover b exec >> throwError err
+
+executeExhaustive :: (MonadIO m) => Backend m -> ScenarioDescription m -> m ()
+executeExhaustive b sc = mapM_ f $ paramSets $ sParams sc
+    where f = execute b sc 
+
+executeMissing :: (MonadIO m) => Backend m -> ScenarioDescription m -> m ()
+executeMissing b sc = do
+    execs <- load b sc
+    let exhaustive = S.fromList $ paramSets (sParams sc)
+    let existing = S.fromList $ map eParamSet execs
+    mapM_ f $ S.toList (exhaustive `S.difference` existing)
+    where f = execute b sc
+
+
+load :: (MonadIO m) => Backend m -> ScenarioDescription m -> m [Execution m]
+load = bLoad
diff --git a/Laborantin/DSL.hs b/Laborantin/DSL.hs
new file mode 100644
--- /dev/null
+++ b/Laborantin/DSL.hs
@@ -0,0 +1,168 @@
+{-# LANGUAGE FlexibleContexts #-}
+
+module Laborantin.DSL (
+        scenario
+    ,   describe
+    ,   parameter
+    ,   values
+    ,   str
+    ,   num
+    ,   range
+    ,   arr
+    ,   setup
+    ,   teardown
+    ,   run
+    ,   param
+    ,   getVar
+    ,   setVar
+    ,   recover
+    ,   analyze
+    ,   result
+    ,   writeResult
+    ,   appendResult
+    ,   logger
+    ,   dbg
+) where
+
+import qualified Data.Map as M
+import Laborantin.Types
+import Control.Monad.State
+import Control.Monad.Reader
+import Control.Monad.Error
+import Control.Applicative
+import Data.Dynamic
+
+class Describable a where
+  changeDescription :: String -> a -> a
+
+instance Describable (ScenarioDescription a) where
+  changeDescription d sc = sc { sDesc = d }
+
+instance Describable ParameterDescription where
+  changeDescription d pa = pa { pDesc = d }
+
+-- | DSL entry point to build a 'ScenarioDescription'.
+scenario :: String -> State (ScenarioDescription m) () -> ScenarioDescription m
+scenario name f = execState f sc0
+  where sc0 = SDesc name "" M.empty M.empty
+
+-- | Attach a description to the 'Parameter' / 'Scnario'
+describe :: Describable a => String -> State a ()
+describe desc = modify (changeDescription desc)
+
+-- | DSL entry point to build a 'ParameterDescription' within a scenario.
+parameter :: String -> State ParameterDescription () -> State (ScenarioDescription m) ()
+parameter name f = modify (addParam name param)
+  where addParam k v sc0 = sc0 { sParams = M.insert k v (sParams sc0) }
+        param = execState f param0
+                where param0 = PDesc name "" []
+
+-- | Set default values for the paramater
+values :: [ParameterValue] -> State ParameterDescription ()
+values xs = do
+  param0 <- get
+  put $ param0 { pValues = xs }
+
+-- | Encapsulate a String as a 'ParameterValue'
+str :: String -> ParameterValue
+str = StringParam
+
+-- | Encapsulate an integer value as a 'ParameterValue'
+num :: Integer -> ParameterValue
+num = NumberParam . fromInteger
+
+-- | Encapsulate a range as a 'ParameterValue'
+range :: Rational -> Rational -> Rational -> ParameterValue
+range = Range
+
+-- | Encapsulate an array of 'str' or 'num' values as a 'ParameterValue'
+arr :: [ParameterValue] -> ParameterValue
+arr = Array
+
+-- | Define the setup hook for this scenario
+setup :: Step m () -> State (ScenarioDescription m) ()
+setup = appendHook "setup"
+
+-- | Define the main run hook for this scenario
+run :: Step m () -> State (ScenarioDescription m) ()
+run = appendHook "run"
+
+-- | Define the teardown hook for this scenario
+teardown :: Step m () -> State (ScenarioDescription m) ()
+teardown  = appendHook "teardown"
+
+-- | Define the recovery hook for this scenario
+recover :: Step m () -> State (ScenarioDescription m) ()
+recover  = appendHook "recover"
+
+-- | Define the offline analysis hook for this scenario
+analyze :: Step m () -> State (ScenarioDescription m) ()
+analyze = appendHook "analyze"
+
+appendHook :: String -> Step m () -> State (ScenarioDescription m) ()
+appendHook name f = modify (addHook name $ Action f)
+  where addHook k v sc0 = sc0 { sHooks = M.insert k v (sHooks sc0) }
+
+-- | Returns a 'Result' object for the given name.
+--
+-- Implementations will return their specific results.
+result :: Monad m => String -> Step m (Result m)
+result name = do 
+  (b,r) <- ask
+  bResult b r name
+
+-- | Write (overwrite) the result in its entirety.
+--
+-- Implementations will return their specific results.
+writeResult :: Monad m => String  -- ^ result name
+                       -> String  -- ^ result content
+                       -> Step m ()
+writeResult name dat = result name >>= flip pWrite dat
+
+-- | Appends a chunk of data to the result. 
+--
+-- Implementations will return their specific results.
+appendResult :: Monad m => String -- ^ result name
+                        -> String -- ^ content to add
+                        -> Step m ()
+appendResult name dat = result name >>= flip pAppend dat
+
+-- | Return a 'LogHandler' object for this scenario.
+logger :: Monad m => Step m (LogHandler m)
+logger = ask >>= uncurry bLogger
+
+-- | Sends a line of data to the logger (debug mode)
+dbg :: Monad m => String -> Step m ()
+dbg msg = logger >>= flip lLog msg
+
+-- | Get the parameter with given name.
+-- Throw an error if the parameter is missing.
+param :: Monad m => String -- ^ the parameter name
+                 -> Step m ParameterValue
+param key = do
+    ret <- liftM (M.lookup key . eParamSet . snd) ask
+    maybe (throwError $ ExecutionError $ "missing param: " ++ key) return ret
+
+getVar' :: (Functor m, MonadState DynEnv m) => String -> m (Maybe Dynamic)
+getVar' k = M.lookup k <$> get
+
+setVar' :: (MonadState DynEnv m) => String -> Dynamic -> m ()
+setVar' k v = modify (M.insert k v)
+
+-- | Set an execution variable.
+setVar :: (Typeable v, MonadState DynEnv m) =>
+            String -- ^ name of the variable
+         -> v      -- ^ value of the variable
+         -> m ()
+setVar k v = setVar' k (toDyn v)
+
+-- | Get an execution variable and tries to cast it from it's Dynamic
+-- representation.
+--
+-- Returns 'Nothing' if the variable is missing or if it could not
+-- be cast to the wanted type.
+getVar :: (Typeable v, Functor m, MonadState DynEnv m) => 
+            String              -- ^ name of the variable
+         -> m (Maybe v)      
+getVar k = maybe Nothing fromDynamic <$> getVar' k
+
diff --git a/Laborantin/Implementation.hs b/Laborantin/Implementation.hs
new file mode 100644
--- /dev/null
+++ b/Laborantin/Implementation.hs
@@ -0,0 +1,146 @@
+{-# LANGUAGE OverloadedStrings #-}
+
+module Laborantin.Implementation (
+        EnvIO, runEnvIO
+    , defaultBackend
+    , defaultResult
+    , defaultLog
+) where
+
+import qualified Data.Map as M
+import qualified Data.Text as T
+import qualified Data.ByteString.Lazy as BSL
+import Laborantin.Types
+import Data.Aeson (decode,encode,FromJSON,parseJSON,(.:),ToJSON,toJSON,(.=),object)
+import qualified Data.Aeson as A
+import qualified Data.Aeson.Types as A
+import Control.Monad.State
+import Control.Applicative ((<$>),(<*>))
+import Data.List
+import Data.UUID
+import System.Directory
+import System.Random
+import System.Log.Logger
+import System.Log.Handler (close)
+import System.Log.Handler.Simple
+import System.Log.Handler.Log4jXML
+
+-- | Default monad for 'defaultBackend'.
+--   EnvIO carries a 'DynEnv' in a state and allows you to perform IO actions.
+type EnvIO = (StateT DynEnv IO)
+
+-- | Execute an EnvIO action in IO.
+runEnvIO :: EnvIO () -> IO DynEnv
+runEnvIO m = snd <$> runStateT m M.empty
+
+instance ToJSON ParameterValue where
+    toJSON (StringParam str) = object ["type" .= ("string"::T.Text), "val" .= T.pack str]
+    toJSON (NumberParam n)   = object ["type" .= ("num"::T.Text), "val" .= n]
+    toJSON (Array xs)        = toJSON xs
+    toJSON (Range _ _ _)     = error "should not have to encode ranges but concrete values instead"
+
+instance ToJSON ExecutionStatus where
+    toJSON = toJSON . show
+
+instance ToJSON (Execution a) where
+    toJSON (Exec sc params path status) = object    [ "scenario-name" .= sName sc
+                                                    , "params" .= params
+                                                    , "path" .= path
+                                                    , "status" .= status
+                                                    ] 
+
+instance FromJSON ParameterValue where
+    parseJSON (A.Object v) = (v .: "type") >>= match
+        where match :: T.Text -> A.Parser ParameterValue
+              match "string" = StringParam <$> v .: "val"
+              match "num"    = NumberParam <$> v .: "val"
+              match "range"  = error "should not have to read ranges"
+              match _        = mzero
+    
+    parseJSON _ = mzero
+
+instance FromJSON ExecutionStatus where
+    parseJSON (A.String txt) = return $ read $ T.unpack txt
+    parseJSON _ = mzero
+
+instance FromJSON StoredExecution where
+    parseJSON (A.Object v) = Stored <$>
+                               v .: "params" <*>
+                               v .: "path" <*>
+                               v .: "status"
+    parseJSON _          = mzero
+
+-- | Default backend for the 'EnvIO' monad.  This backend uses the filesystem
+-- as storage and UUIDs for scenario instances (supposes that UUID collision
+-- cannot happen).
+--
+-- Parameters, logfiles, and result data all are stored in a unique directory named
+-- ./<scenario-name>/<uuid>
+-- 
+-- Results are individual files in this directory. There is no namespacing
+-- hence avoid the following names: 'execution.json', 'execution-log.txt', and
+-- 'execution-log.xml'. These three files are the scenario execution metadata
+-- and logs.
+--
+defaultBackend :: Backend EnvIO
+defaultBackend = Backend "default EnvIO backend" prepare finalize setup run teardown analyze recover result load log
+  where prepare :: ScenarioDescription EnvIO -> ParameterSet -> EnvIO (Execution EnvIO,Finalizer EnvIO)
+        prepare sc params = do
+                  uuid <- liftIO (randomIO :: IO UUID)
+                  let rundir = intercalate "/" [sName sc, show uuid]
+                  let exec = Exec sc params rundir Running
+                  handles <- liftIO $ do
+                    createDirectoryIfMissing True rundir
+                    BSL.writeFile (rundir ++ "/execution.json") (encode exec)
+                    updateGlobalLogger (loggerName exec) (setLevel DEBUG)
+                    h1 <- fileHandler (rundir ++ "/execution-log.txt") DEBUG
+                    h2 <- log4jFileHandler (rundir ++ "/execution-log.xml") DEBUG
+                    forM_ [h1,h2] (updateGlobalLogger (loggerName exec) . addHandler)
+                    putStrLn $ advertise exec
+                    return [h1,h2]
+                  return (exec, \_ -> liftIO $ forM_ handles close)
+                  where advertise exec = unlines $ map ($ exec) [show. sName . eScenario
+                                                , show . eParamSet
+                                                , ePath]
+        finalize  exec finalizer = do
+                            finalizer exec
+                            liftIO . putStrLn $ "done"
+                            liftIO $ BSL.writeFile (rundir ++ "/execution.json") (encode exec)
+                            where rundir = ePath exec
+        setup             = callHooks "setup" . eScenario
+        run               = callHooks "run" . eScenario
+        teardown          = callHooks "teardown" . eScenario
+        analyze           = callHooks "analyze" . eScenario
+        recover           = callHooks "recover" . eScenario
+        callHooks key sc  = maybe (error $ "no such hook: " ++ key) unAction (M.lookup key $ sHooks sc)
+        result exec       = return . defaultResult exec
+
+        load :: ScenarioDescription EnvIO -> EnvIO [Execution EnvIO]
+        load sc           = liftIO $ do
+            dirs <- filter notDot <$> getDirectoryContents (sName sc)
+            let paths = map ((sName sc ++ "/") ++) dirs
+            mapM loadOne paths
+            where notDot dirname = take 1 dirname /= "."
+                  loadOne path = do
+                    exec' <- liftM forStored . decode <$> BSL.readFile (path ++ "/execution.json")
+                    maybe (error $ "decoding: " ++ path) return exec'
+
+                    where forStored (Stored params path status) = Exec sc params path status
+        log exec          = return $ defaultLog exec
+
+-- | Default result handler for the 'EnvIO' monad (see 'defaultBackend').
+defaultResult :: Execution m -> String -> Result EnvIO
+defaultResult exec name = Result path read append write
+  where read        = liftIO $ readFile path
+        append dat  = liftIO $ appendFile path dat
+        write dat   = liftIO $ writeFile path dat
+        path        = intercalate "/" [ePath exec, name]
+
+-- | Default logger for the 'EnvIO' monad (see 'defaultBackend').
+defaultLog :: Execution m -> LogHandler EnvIO
+defaultLog exec = LogHandler logF
+    where logF msg = liftIO $ debugM (loggerName exec) msg
+          path = ePath exec ++ "/execution.log"
+
+loggerName :: Execution m -> String
+loggerName exec = "laborantin:" ++ ePath exec
diff --git a/Laborantin/Types.hs b/Laborantin/Types.hs
new file mode 100644
--- /dev/null
+++ b/Laborantin/Types.hs
@@ -0,0 +1,110 @@
+{-# LANGUAGE TupleSections #-}
+
+module Laborantin.Types (
+        ScenarioDescription (..)
+    ,   ParameterDescription (..)
+    ,   ParameterValue (..)
+    ,   ParameterSpace
+    ,   ParameterSet
+    ,   paramSets
+    ,   Result (..)
+    ,   Backend (..)
+    ,   Execution (..)
+    ,   StoredExecution (..)
+    ,   ExecutionError (..)
+    ,   ExecutionStatus (..)
+    ,   Finalizer (..)
+    ,   LogHandler (..)
+    ,   Step
+    ,   Action (..)
+    ,   DynEnv (..)
+) where
+
+import qualified Data.Map as M
+import Control.Monad.Reader
+import Control.Monad.Error
+import Data.Dynamic
+
+type DynEnv = M.Map String Dynamic
+type ParameterSpace = M.Map String ParameterDescription
+data ExecutionError = ExecutionError String
+    deriving (Show)
+instance Error ExecutionError where
+  noMsg    = ExecutionError "A String Error!"
+  strMsg   = ExecutionError
+type Step m a = ErrorT ExecutionError (ReaderT (Backend m,Execution m) m) a
+
+newtype Action m = Action { unAction :: Step m () }
+
+instance Show (Action m) where
+  show _ = "(Action)"
+
+data ScenarioDescription m = SDesc {
+    sName   :: String
+  , sDesc   :: String
+  , sParams :: ParameterSpace
+  , sHooks  :: M.Map String (Action m)
+  } deriving (Show)
+
+data ParameterDescription = PDesc {
+    pName   :: String
+  , pDesc   :: String
+  , pValues :: [ParameterValue]
+  } deriving (Show,Eq,Ord)
+
+data ParameterValue = StringParam String 
+  | NumberParam Rational
+  | Array [ParameterValue]
+  | Range Rational Rational Rational -- [from, to], by increment
+  deriving (Show,Eq,Ord)
+
+type ParameterSet = M.Map String ParameterValue
+
+data ExecutionStatus = Running | Success | Failure 
+  deriving (Show,Read)
+
+data Execution m = Exec {
+    eScenario :: ScenarioDescription m
+  , eParamSet :: ParameterSet
+  , ePath     :: String
+  , eStatus   :: ExecutionStatus
+} deriving (Show)
+
+data StoredExecution = Stored {
+    seParamSet :: ParameterSet
+  , sePath     :: String
+  , seStatus   :: ExecutionStatus
+} deriving (Show)
+
+expandValue :: ParameterValue -> [ParameterValue]
+expandValue (Range from to by)  = map NumberParam [from,from+by .. to]
+expandValue x                   = [x]
+
+paramSets :: ParameterSpace -> [ParameterSet]
+paramSets ps = map M.fromList $ sequence possibleValues
+    where possibleValues = map f $ M.toList ps
+          f (k,desc) = concatMap (map (pName desc,) . expandValue) $ pValues desc
+type Finalizer m = Execution m -> m ()
+
+data Backend m = Backend {
+    bName      :: String
+  , bPrepareExecution  :: ScenarioDescription m -> ParameterSet -> m (Execution m,Finalizer m)
+  , bFinalizeExecution :: Execution m -> Finalizer m -> m ()
+  , bSetup     :: Execution m -> Step m ()
+  , bRun       :: Execution m -> Step m ()
+  , bTeardown  :: Execution m -> Step m ()
+  , bAnalyze   :: Execution m -> Step m ()
+  , bRecover   :: Execution m -> Step m ()
+  , bResult    :: Execution m -> String -> Step m (Result m)
+  , bLoad      :: ScenarioDescription m -> m [Execution m]
+  , bLogger    :: Execution m -> Step m (LogHandler m)
+}
+
+data Result m = Result {
+    pPath   :: String
+  , pRead   :: Step m String
+  , pAppend :: String -> Step m ()
+  , pWrite  :: String -> Step m ()
+}
+
+newtype LogHandler m = LogHandler { lLog :: String -> Step m () }
diff --git a/README.md b/README.md
new file mode 100644
--- /dev/null
+++ b/README.md
@@ -0,0 +1,14 @@
+laborantin-hs
+=============
+
+Haskell meets Laborantin
+
+
+# TODO
+
+* more doc
+* use Text rather than String where appropriate
+* defaultMain with run/describe/find/analyze/rm modes
+* in-memory (pure?) backend
+* dependency annotations
+* configuration reader
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/laborantin-hs.cabal b/laborantin-hs.cabal
new file mode 100644
--- /dev/null
+++ b/laborantin-hs.cabal
@@ -0,0 +1,25 @@
+-- Initial laborantin-hs.cabal generated by cabal init.  For further 
+-- documentation, see http://haskell.org/cabal/users-guide/
+
+name:                laborantin-hs
+version:             0.1.0.0
+synopsis:            an experiment management framework
+-- description:         
+homepage:            https://github.com/lucasdicioccio/laborantin-hs
+license:             Apache-2.0
+license-file:        LICENSE
+author:              lucas dicioccio
+maintainer:          lucas@dicioccio.fr
+-- copyright:           
+category:            Experiment
+build-type:          Simple
+extra-source-files:  README.md
+cabal-version:       >=1.10
+
+library
+  exposed-modules:     Laborantin, Laborantin.DSL, Laborantin.Implementation, Laborantin.Types
+  -- other-modules:       
+  other-extensions:    FlexibleContexts, OverloadedStrings, TupleSections
+  build-depends:       base >=4.6 && <4.7, transformers >=0.3 && <0.4, mtl >=2.1 && <2.2, containers >=0.5 && <0.6, text >=0.11 && <0.12, bytestring >=0.10 && <0.11, aeson >=0.6 && <0.7, uuid >=1.2 && <1.3, directory >=1.2 && <1.3, random >=1.0 && <1.1, hslogger >=1.2 && <1.3
+  -- hs-source-dirs:      
+  default-language:    Haskell2010
