diff --git a/app/MeteorCounter/FTL.hs b/app/MeteorCounter/FTL.hs
index f352db1..8e82a8b 100644
--- a/app/MeteorCounter/FTL.hs
+++ b/app/MeteorCounter/FTL.hs
@@ -1,29 +1,27 @@
+{-# LANGUAGE UndecidableInstances #-}
+{-# LANGUAGE GeneralizedNewtypeDeriving #-}
 module FTL where
 
 import qualified Data.Map                as Map
 import qualified Data.Set                as Set
 
 import           FTLTypes
-import qualified Hydra.Domain            as D
 import qualified Hydra.FTL               as L
 import           Hydra.Prelude
 import qualified Hydra.Runtime           as R
 import           Types
 
-import qualified Control.Monad.IO.Unlift as UIO
-import qualified UnliftIO.Concurrent     as UIO
-
 import           Hydra.FTLI              ()
 
 delayFactor :: Int
 delayFactor = 100
 
-initState :: AppConfig -> STM AppState'
+initState :: L.StateL m => AppConfig -> m (AppState' m)
 initState cfg = do
-  ne <- newTVar Set.empty
-  nw <- newTVar Set.empty
-  se <- newTVar Set.empty
-  sw <- newTVar Set.empty
+  ne <- L.newVar Set.empty
+  nw <- L.newVar Set.empty
+  se <- L.newVar Set.empty
+  sw <- L.newVar Set.empty
 
   let catalogue = Map.fromList
         [ (NorthEast, ne)
@@ -32,9 +30,9 @@ initState cfg = do
         , (SouthWest, sw)
         ]
 
-  published <- newTVar Set.empty
-  total    <- newTVar 0
-  pure $ AppState' catalogue total published cfg
+  publised <- L.newVar Set.empty
+  total    <- L.newVar 0
+  pure $ AppState' catalogue total publised cfg
 
 getRandomMeteor :: L.RandomL m => Region -> m Meteor
 getRandomMeteor region = do
@@ -47,64 +45,76 @@ getRandomMilliseconds = L.getRandomInt (0, 3000)
 
 withRandomDelay
   :: (L.ControlFlowL m, L.RandomL m)
-  => AppState' -> m () -> m ()
+  => AppState' t -> m () -> m ()
 withRandomDelay st action = do
   when (delaysEnabled' st)
     $ getRandomMilliseconds >>= \d -> L.delay $ d * dFactor' st
   action
 
-publishMeteor :: AppState' -> Meteor -> STM ()
+publishMeteor :: L.StateL m => AppState' m -> Meteor -> m ()
 publishMeteor st meteor =
-  modifyTVar (_channel' st) $ Set.insert meteor
+  L.modifyVar (_channel' st) $ Set.insert meteor
 
 meteorShower
-  :: (UIO.MonadUnliftIO m, L.LoggerL m, L.RandomL m)
-  => AppState' -> Region -> m ()
+  :: (Lang m)
+  => AppState' (L.Transaction m) -> Region -> m ()
 meteorShower st region = do
   meteor <- getRandomMeteor region
   when (doLogDiscovered' st) $ L.logInfo $ "New meteor discovered: " <> show meteor
-  atomically $ publishMeteor st meteor
+  L.transaction $ publishMeteor st meteor
 
 trackMeteor
-  :: (UIO.MonadUnliftIO m, L.LoggerL m)
-  => AppState' -> Meteor -> m ()
+  :: (Lang m)
+  => AppState' (L.Transaction m) -> Meteor -> m ()
 trackMeteor st meteor = do
   let region = _region meteor
   case Map.lookup region (_catalogue' st) of
     Nothing -> L.logError $ "Region not found: " <> show region
     Just r  -> do
       when (storeTrackedMeteors' st) $
-        atomically $ modifyTVar r $ Set.insert meteor
+        L.transaction $ L.modifyVar r $ Set.insert meteor
       when (doLogTracked' st) $ L.logInfo $ "New meteor tracked: " <> show meteor
 
-meteorCounter :: (UIO.MonadUnliftIO m, L.LoggerL m) => AppState' -> m ()
+meteorCounter :: (Lang m) => AppState' (L.Transaction m) -> m ()
 meteorCounter st = do
-  untracked <- atomically $ do
-    ps <- readTVar (_channel' st)
-    when (Set.null ps) retry
-    writeTVar (_channel' st) Set.empty
-    pure $ Set.toList ps
+  untracked <- L.transaction $ do
+     ps <- L.readVar (_channel' st)
+     when (Set.null ps) L.retry
+     L.writeVar (_channel' st) Set.empty
+     pure $ Set.toList ps
   mapM_ (trackMeteor st) untracked
 
-  atomically $ modifyTVar (_totalMeteors' st) $ (+(length untracked))
-  total <- readTVarIO (_totalMeteors' st)
+  L.transaction $ L.modifyVar (_totalMeteors' st) $ (+(length untracked))
+  total <- L.transaction $ L.readVar (_totalMeteors' st)
 
   when (doLogTotal' st) $ L.logInfo $ "Total tracked: " <> show total
 
-meteorsMonitoring :: (UIO.MonadUnliftIO m, L.ControlFlowL m, L.LoggerL m, L.RandomL m) => AppConfig -> m ()
-meteorsMonitoring cfg = do
-  st <- atomically $ initState cfg
+meteorsMonitoring :: (Lang m, L.Transaction m ~ t) => AppConfig -> AppState' t -> m ()
+meteorsMonitoring cfg st = do
+  _ <- L.forkProcess $ forever $ meteorCounter st
+  _ <- L.forkProcess $ forever $ withRandomDelay st $ meteorShower st NorthEast
+  _ <- L.forkProcess $ forever $ withRandomDelay st $ meteorShower st NorthWest
+  _ <- L.forkProcess $ forever $ withRandomDelay st $ meteorShower st SouthEast
+  _ <- L.forkProcess $ forever $ withRandomDelay st $ meteorShower st SouthWest
 
-  UIO.forkIO $ forever $ meteorCounter st
-  UIO.forkIO $ forever $ withRandomDelay st $ meteorShower st NorthEast
-  UIO.forkIO $ forever $ withRandomDelay st $ meteorShower st NorthWest
-  UIO.forkIO $ forever $ withRandomDelay st $ meteorShower st SouthEast
-  UIO.forkIO $ forever $ withRandomDelay st $ meteorShower st SouthWest
-
-  atomically $ do
+  L.transaction $ do
     let maxTotal = fromMaybe 0 $ maxMeteors cfg
-    total <- readTVar $ _totalMeteors' st
-    when (maxTotal == 0 || total < maxTotal) retry
+    total <- L.readVar $ _totalMeteors' st
+    when (maxTotal == 0 || total < maxTotal) L.retry
 
 scenario :: R.CoreRuntime -> AppConfig -> IO ()
-scenario coreRt cfg = void $ runReaderT (meteorsMonitoring cfg) coreRt
+scenario coreRt cfg = void $ do
+   st <- atomically $ initState cfg
+   runReaderT (runAppM $ meteorsMonitoring cfg st) coreRt
+
+newtype AppM a = AppM { runAppM :: ReaderT R.CoreRuntime IO a }
+  deriving (Functor, Applicative, Monad, L.ControlFlowL, L.LoggerL, L.RandomL, L.ProcessL)
+
+class (L.StateL (L.Transaction m), L.Atomic m,
+  L.StateL (L.Transaction m), L.LoggerL m, L.RandomL m, L.ControlFlowL m, L.ProcessL m) => Lang m
+instance Lang AppM
+
+instance L.Atomic AppM where
+  type Transaction AppM = STM
+  transaction = AppM . atomically
+
diff --git a/app/MeteorCounter/FTLTypes.hs b/app/MeteorCounter/FTLTypes.hs
index 04ff940..b9e6a97 100644
--- a/app/MeteorCounter/FTLTypes.hs
+++ b/app/MeteorCounter/FTLTypes.hs
@@ -3,28 +3,28 @@ module FTLTypes where
 import qualified Data.Map      as Map
 import qualified Data.Set      as Set
 
-import qualified Hydra.Domain  as D
 import           Hydra.Prelude
-import qualified Hydra.Runtime as R
+import           Hydra.FTL     as L
 import           Types
 
-type Meteors' = TVar (Set.Set Meteor)
+type Meteors' m = L.StateVar m (Set.Set Meteor)
 
-type Catalogue' = Map.Map Region Meteors'
+type Catalogue' m = Map.Map Region (Meteors' m)
 
-data AppState' = AppState'
-  { _catalogue'    :: Catalogue'
-  , _totalMeteors' :: TVar Int
-  , _channel'      :: TVar (Set.Set Meteor)
+data AppState' m = AppState'
+  { _catalogue'    :: Catalogue' m
+  , _totalMeteors' :: L.StateVar m Int
+  , _channel'      :: L.StateVar m (Set.Set Meteor)
   , _config'       :: AppConfig
   }
 
-delaysEnabled' :: AppState' -> Bool
+
+delaysEnabled' :: AppState' m -> Bool
 delaysEnabled' = enableDelays . _config'
 
 dFactor' = delaysFactor . _config'
 
-storeTrackedMeteors' :: AppState' -> Bool
+storeTrackedMeteors' :: AppState' m -> Bool
 storeTrackedMeteors' = storeTracked . _config'
 
 doLogDiscovered' = logDiscovered . _config'
diff --git a/src/Hydra/Core/ControlFlow/FTL.hs b/src/Hydra/Core/ControlFlow/FTL.hs
index b97e241..51b24ea 100644
--- a/src/Hydra/Core/ControlFlow/FTL.hs
+++ b/src/Hydra/Core/ControlFlow/FTL.hs
@@ -4,3 +4,11 @@ import           Hydra.Prelude
 
 class Monad m => ControlFlowL m where
   delay :: Int -> m ()
+
+instance ControlFlowL IO where
+  delay = threadDelay
+  {-# INLINE delay #-}
+
+instance ControlFlowL (ReaderT e IO) where
+  delay = lift . threadDelay
+  {-# INLINE delay #-}
diff --git a/src/Hydra/Core/ControlFlow/FTLI.hs b/src/Hydra/Core/ControlFlow/FTLI.hs
deleted file mode 100644
index 638821c..0000000
--- a/src/Hydra/Core/ControlFlow/FTLI.hs
+++ /dev/null
@@ -1,10 +0,0 @@
-module Hydra.Core.ControlFlow.FTLI where
-
-import           Hydra.Prelude
-
-import qualified Hydra.Core.FTL     as L
-import qualified Hydra.Core.RLens   as RLens
-import qualified Hydra.Core.Runtime as R
-
-instance MonadIO m => L.ControlFlowL (ReaderT R.CoreRuntime m) where
-    delay = liftIO . threadDelay
diff --git a/src/Hydra/Core/FTL.hs b/src/Hydra/Core/FTL.hs
index 17a99dc..ef5954c 100644
--- a/src/Hydra/Core/FTL.hs
+++ b/src/Hydra/Core/FTL.hs
@@ -7,5 +7,5 @@ import           Hydra.Core.Lang.FTL        as X
 import           Hydra.Core.Logger.FTL      as X
 import           Hydra.Core.Process.FTL     as X
 import           Hydra.Core.Random.FTL      as X
--- import           Hydra.Core.State.FTL       as X
-import           Hydra.Core.State.Language  as X
+import           Hydra.Core.State.FTL       as X
+-- import           Hydra.Core.State.Language  as X
diff --git a/src/Hydra/Core/FTLI.hs b/src/Hydra/Core/FTLI.hs
index 630437b..3b338c0 100644
--- a/src/Hydra/Core/FTLI.hs
+++ b/src/Hydra/Core/FTLI.hs
@@ -2,9 +2,7 @@ module Hydra.Core.FTLI
   ( module X
   ) where
 
-import           Hydra.Core.ControlFlow.FTLI as X
 import           Hydra.Core.Lang.FTLI        as X
 import           Hydra.Core.Logger.FTLI      as X
 import           Hydra.Core.Process.FTLI     as X
 import           Hydra.Core.Random.FTLI      as X
-import           Hydra.Core.State.FTLI       as X
diff --git a/src/Hydra/Core/Lang/FTL.hs b/src/Hydra/Core/Lang/FTL.hs
index 8377bce..7193e10 100644
--- a/src/Hydra/Core/Lang/FTL.hs
+++ b/src/Hydra/Core/Lang/FTL.hs
@@ -13,7 +13,7 @@ import           Hydra.Core.Random.FTL      as L
 import qualified Hydra.Core.State.Class     as L
 import qualified Hydra.Core.State.Language  as L
 
-class (Monad m, L.ControlFlowL m, L.RandomL m, L.LoggerL m) => LangL m where
+class (Monad m, L.RandomL m, L.LoggerL m) => LangL m where
   evalStateAtomically :: L.StateL a -> m a
 
 instance (Monad m, LangL m) => L.StateIO m where
diff --git a/src/Hydra/Core/Lang/FTLI.hs b/src/Hydra/Core/Lang/FTLI.hs
index 976dfad..85ebdc8 100644
--- a/src/Hydra/Core/Lang/FTLI.hs
+++ b/src/Hydra/Core/Lang/FTLI.hs
@@ -2,7 +2,6 @@ module Hydra.Core.Lang.FTLI where
 
 import           Hydra.Prelude
 
-import           Hydra.Core.ControlFlow.FTLI  ()
 import qualified Hydra.Core.FTL               as L
 import           Hydra.Core.Logger.FTLI       ()
 import           Hydra.Core.Random.FTLI       ()
diff --git a/src/Hydra/Core/Process/FTL.hs b/src/Hydra/Core/Process/FTL.hs
index aac3dec..ce0f70f 100644
--- a/src/Hydra/Core/Process/FTL.hs
+++ b/src/Hydra/Core/Process/FTL.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE FunctionalDependencies #-}
 {-# LANGUAGE FlexibleContexts      #-}
 {-# LANGUAGE GADTs                 #-}
 {-# LANGUAGE MultiParamTypeClasses #-}
@@ -5,14 +6,35 @@
 
 module Hydra.Core.Process.FTL where
 
-import           Hydra.Prelude
+import           Hydra.Prelude hiding (atomically)
 
-import qualified Hydra.Core.Domain    as D
+import Control.Concurrent
+import Control.Concurrent.STM
 
+class (Monad m) => ProcessL m where
+  type ProcessHandle m :: * -> *
+  forkProcess  :: m a -> m (ProcessHandle m a)
+  killProcess  :: ProcessHandle m a -> m ()
+  tryGetResult :: ProcessHandle m a -> m (Maybe a)
+  awaitResult  :: ProcessHandle m a -> m a
 
+newtype H a = H { unH :: (ThreadId, TMVar (Either SomeException a)) }
 
--- class (Monad m) => ProcessL m where
---   forkProcess  :: m' a -> m (D.ProcessPtr a)
-  -- killProcess  :: D.ProcessPtr a -> m ()
-  -- tryGetResult :: D.ProcessPtr a -> m (Maybe a)
-  -- awaitResult  :: D.ProcessPtr a -> m a
+instance ProcessL (ReaderT e IO) where
+  type ProcessHandle (ReaderT e IO) = H
+  forkProcess f = ReaderT $ \e -> do
+     z <- newEmptyTMVarIO
+     t <- forkIOWithUnmask $ \restore -> do
+       x <- (restore $ runReaderT f e) `catch` (\e -> do
+          atomically $ putTMVar z (Left e)
+          throwM e)
+       atomically $ putTMVar z (Right x)
+     pure $ H (t,z)
+  killProcess = ReaderT . const . killThread . fst . unH
+  tryGetResult (H (_,e)) = ReaderT $ const $ atomically (tryReadTMVar e) >>=
+    traverse (\case
+      Left e -> throwM e
+      Right x -> pure x)
+  awaitResult (H (_,e)) = ReaderT $ const $ atomically (readTMVar e) >>= \case
+    Left e -> throwM e
+    Right x -> pure x
diff --git a/src/Hydra/Core/State/FTL.hs b/src/Hydra/Core/State/FTL.hs
index 7c9bda1..7513400 100644
--- a/src/Hydra/Core/State/FTL.hs
+++ b/src/Hydra/Core/State/FTL.hs
@@ -1,30 +1,45 @@
+{-# LANGUAGE AllowAmbiguousTypes #-}
+{-# LANGUAGE FunctionalDependencies #-}
+{-# LANGUAGE ScopedTypeVariables #-}
 module Hydra.Core.State.FTL where
 
 import           Hydra.Prelude
+import Control.Concurrent.STM as STM
 
-import qualified Hydra.Core.Domain as D
+-- import qualified Hydra.Core.Domain as D
 
--- class Monad m => StateL m where
---   newVar   :: a -> m (D.StateVar a)
---   readVar  :: D.StateVar a -> m a
---   writeVar :: D.StateVar a -> a -> m ()
---   retry    :: m a
+class Monad m => StateL m where
+  type StateVar m :: * -> *
+  newVar   :: a -> m (StateVar m a)
+  readVar  :: StateVar m a -> m a
+  writeVar :: StateVar m a -> a -> m ()
+  retry    :: m a
 
 -- -- | Modify variable with function.
--- modifyVar :: StateL m => D.StateVar a -> (a -> a) -> m ()
--- modifyVar var f = readVar var >>= writeVar var . f
+modifyVar :: StateL m => StateVar m a -> (a -> a) -> m ()
+modifyVar var f = readVar var >>= writeVar var . f
+{-# SPECIALIZE modifyVar :: TVar a -> (a -> a) -> STM () #-}
 
+instance StateL STM where
+  type StateVar STM = TVar
+  newVar = newTVar
+  {-# INLINE newVar #-}
+  readVar = readTVar
+  {-# INLINE readVar #-}
+  writeVar = writeTVar
+  {-# INLINE writeVar #-}
+  retry = STM.retry
+  {-# INLINE retry #-}
 
--- class StateIO m where
---   atomically :: StateL a -> m a
---   newVarIO :: a -> m (D.StateVar a)
---   readVarIO :: D.StateVar a -> m a
---   writeVarIO :: D.StateVar a -> a -> m ()
---
+-- | Class that defines how can we run internal nested transaction in the
+-- current computation.
+class Atomic m where
+  type Transaction m :: * -> *
+  transaction :: (Transaction m) a -> m a
 
 -- -- -- | Eval "delayed" logger: it will be written after successfull state operation.
 -- -- evalStmLogger :: L.LoggerL () -> StateL ()
 -- -- evalStmLogger action = liftF $ EvalStmLogger action id
 --
 -- -- instance L.Logger StateL where
--- --     logMessage level = evalStmLogger . L.logMessage level
+-- --    logMessage level = evalStmLogger . L.logMessage level
diff --git a/src/Hydra/Core/State/FTLI.hs b/src/Hydra/Core/State/FTLI.hs
deleted file mode 100644
index 802fc6b..0000000
--- a/src/Hydra/Core/State/FTLI.hs
+++ /dev/null
@@ -1,23 +0,0 @@
-module Hydra.Core.State.FTLI where
-
-import           Hydra.Prelude
-
-import qualified Hydra.Core.Domain            as D
-import qualified Hydra.Core.FTL               as L
-import qualified Hydra.Core.RLens             as RLens
-import qualified Hydra.Core.Runtime           as R
-
-import qualified Hydra.Core.State.Interpreter as Impl
--- 
--- instance L.StateL (ReaderT R.CoreRuntime STM) where
---   newVar val = do
---     coreRt <- ask
---     r <- lift $ Impl.newVar' (coreRt ^. RLens.stateRuntime) val
---     pure $ D.StateVar r
---   readVar var = do
---     coreRt <- ask
---     lift $ Impl.readVar' (coreRt ^. RLens.stateRuntime) var
---   writeVar var val = do
---     coreRt <- ask
---     lift $ Impl.writeVar' (coreRt ^. RLens.stateRuntime) var val
---   retry    = lift retry