diff --git a/examples/categorifier-c-examples.cabal b/examples/categorifier-c-examples.cabal
index 037ec0c..10e0ed0 100644
--- a/examples/categorifier-c-examples.cabal
+++ b/examples/categorifier-c-examples.cabal
@@ -278,3 +278,46 @@ executable th-compile
     , categorifier-unconcat-category
     , categorifier-unconcat-integration
   default-language: Haskell2010
+
+executable grad-descent
+  hs-source-dirs: grad-descent
+  main-is: Main.hs
+  other-modules:
+      F
+  ghc-options:
+      -O0
+      -ddump-splices
+      -fexpose-all-unfoldings
+      -fmax-simplifier-iterations=0
+      -fno-ignore-interface-pragmas
+      -fno-omit-interface-pragmas
+      -Wall
+      -fplugin Categorifier
+      -fplugin-opt Categorifier:hierarchy:Categorifier.Hierarchy.UnconCat.hierarchy
+      -fplugin-opt Categorifier:hierarchy:Categorifier.Hierarchy.ConCat.functionHierarchy
+      -fplugin-opt Categorifier:hierarchy:Categorifier.Hierarchy.ConCatExtensions.hierarchy
+      -fplugin-opt Categorifier:maker-map:Categorifier.Core.MakerMap.baseMakerMapFun
+      -fplugin-opt Categorifier:maker-map:Categorifier.C.MakerMap.cMakerMapFun
+      -fplugin-opt Categorifier:autointerpreter:Categorifier.C.UnconCat.tryAutoInterpret
+      -optc-Wno-implicit-function-declaration
+      -fprint-potential-instances
+  build-depends:
+      base
+    , ghc-prim
+    , concat-classes
+    , categorifier-c
+    , categorifier-c-hk-classes
+    , categorifier-c-maker-map
+    , categorifier-c-test-lib
+    , categorifier-c-unconcat
+    , categorifier-category
+    , categorifier-client
+    , categorifier-concat-extensions-category
+    , categorifier-concat-extensions-integration
+    , categorifier-concat-integration
+    , categorifier-plugin
+    , categorifier-unconcat-category
+    , categorifier-unconcat-integration
+    , ad
+    , reflection
+  default-language: Haskell2010
diff --git a/examples/grad-descent/F.hs b/examples/grad-descent/F.hs
new file mode 100644
index 0000000..001ab5f
--- /dev/null
+++ b/examples/grad-descent/F.hs
@@ -0,0 +1,132 @@
+{-# LANGUAGE DataKinds #-}
+{-# LANGUAGE DeriveGeneric #-}
+{-# LANGUAGE FlexibleContexts #-}
+{-# LANGUAGE FlexibleInstances #-}
+{-# LANGUAGE MultiParamTypeClasses #-}
+{-# LANGUAGE RankNTypes #-}
+{-# LANGUAGE ScopedTypeVariables #-}
+{-# LANGUAGE StandaloneDeriving #-}
+{-# LANGUAGE TemplateHaskell #-}
+{-# LANGUAGE TypeApplications #-}
+{-# LANGUAGE TypeFamilies #-}
+{-# LANGUAGE TypeOperators #-}
+{-# LANGUAGE UndecidableInstances #-}
+
+module F
+  ( Input (..),
+    Output (..),
+    Param (..),
+    XY (..),
+    rosenbrock,
+    dRosenbrock,
+    wrap_rosenbrockF,
+    wrap_dRosenbrockF,
+  )
+where
+
+import qualified Categorifier.C.CExpr.Cat as C
+import Categorifier.C.CExpr.Cat.TargetOb (TargetOb, TargetObTC1)
+import Categorifier.C.CExpr.Types.Core (CExpr)
+import Categorifier.C.CTypes.CGeneric (CGeneric)
+import qualified Categorifier.C.CTypes.CGeneric as CG
+import Categorifier.C.CTypes.GArrays (GArrays)
+import Categorifier.C.KTypes.C (C)
+import Categorifier.C.KTypes.Function (kFunctionCall)
+import Categorifier.C.KTypes.KType1 (KType1)
+import qualified Categorifier.Categorify as Categorify
+import qualified Categorifier.Category as Category
+import Categorifier.Client (deriveHasRep)
+import Data.Int (Int32)
+import Data.Proxy (Proxy (..))
+import Data.Reflection (Reifies)
+import Data.Word (Word64)
+import GHC.Generics (Generic)
+import Numeric.AD (grad)
+import Numeric.AD.Internal.Reverse (Reverse (Lift), Tape)
+
+data Param f = Param
+  { paramA :: f Double,
+    paramB :: f Double
+  }
+  deriving (Generic)
+
+deriving instance Show (Param C)
+
+deriveHasRep ''Param
+
+instance CGeneric (Param f)
+
+instance GArrays f (Param f)
+
+type instance TargetOb (Param f) = Param (TargetObTC1 f)
+
+data XY f = XY
+  { xyX :: f Double,
+    xyY :: f Double
+  }
+  deriving (Generic)
+
+deriving instance Show (XY C)
+
+deriveHasRep ''XY
+
+instance CGeneric (XY f)
+
+instance GArrays f (XY f)
+
+type instance TargetOb (XY f) = XY (TargetObTC1 f)
+
+data Input f = Input
+  { iParam :: Param f,
+    iCoord :: XY f
+  }
+  deriving (Generic)
+
+deriving instance Show (Input C)
+
+deriveHasRep ''Input
+
+instance CGeneric (Input f)
+
+instance GArrays f (Input f)
+
+type instance TargetOb (Input f) = Input (TargetObTC1 f)
+
+newtype Output f = Output
+  {oF :: f Double}
+  deriving (Generic)
+
+deriving instance Show (Output C)
+
+deriveHasRep ''Output
+
+instance CGeneric (Output f)
+
+instance GArrays f (Output f)
+
+type instance TargetOb (Output f) = Output (TargetObTC1 f)
+
+rosenbrock :: Num a => (a, a) -> (a, a) -> a
+rosenbrock (a, b) (x, y) = (a - x) ^ 2 + b * (y - x ^ 2) ^ 2
+
+dRosenbrock :: forall a. Num a => (a, a) -> (a, a) -> (a, a)
+dRosenbrock (a, b) (x, y) =
+  let rosenbrock' :: forall s. Reifies s Tape => [Reverse s a] -> Reverse s a
+      rosenbrock' [x', y'] =
+        let a' = Lift a
+            b' = Lift b
+         in rosenbrock (a', b') (x', y')
+      [dfdx, dfdy] = grad rosenbrock' [x, y]
+   in (dfdx, dfdy)
+
+rosenbrockF :: KType1 f => Input f -> Output f
+rosenbrockF (Input (Param a b) (XY x y)) = Output $ rosenbrock (a, b) (x, y)
+
+dRosenbrockF :: forall f. (KType1 f) => Input f -> XY f
+dRosenbrockF (Input (Param a b) (XY x y)) =
+  let (dfdx, dfdy) = dRosenbrock (a, b) (x, y)
+   in XY dfdx dfdy
+
+$(Categorify.separately 'rosenbrockF [t|C.Cat|] [pure [t|C|]])
+
+$(Categorify.separately 'dRosenbrockF [t|C.Cat|] [pure [t|C|]])
diff --git a/examples/grad-descent/Main.hs b/examples/grad-descent/Main.hs
new file mode 100644
index 0000000..b88e548
--- /dev/null
+++ b/examples/grad-descent/Main.hs
@@ -0,0 +1,68 @@
+{-# LANGUAGE ForeignFunctionInterface #-}
+{-# LANGUAGE OverloadedStrings #-}
+{-# LANGUAGE TemplateHaskell #-}
+{-# LANGUAGE TypeApplications #-}
+
+module Main where
+
+import Categorifier.C.Codegen.FFI.TH (embedFunction)
+import Categorifier.C.KTypes.C (C (unsafeC))
+import Categorifier.C.KTypes.KLiteral (kliteral)
+import Data.Foldable (traverse_)
+import F
+  ( Input (..),
+    Output (..),
+    Param (..),
+    XY (..),
+    dRosenbrock,
+    rosenbrock,
+    wrap_dRosenbrockF,
+    wrap_rosenbrockF,
+  )
+
+$(embedFunction "rosenbrockF" wrap_rosenbrockF)
+
+$(embedFunction "dRosenbrockF" wrap_dRosenbrockF)
+
+gamma :: Double
+gamma = 0.01
+
+step ::
+  ((Double, Double) -> IO Double) ->
+  ((Double, Double) -> IO (Double, Double)) ->
+  (Double, Double) ->
+  IO (Double, Double)
+step _f df (x0, y0) = do
+  (dfdx, dfdy) <- df (x0, y0)
+  let (x1, y1) = (x0 - gamma * dfdx, y0 - gamma * dfdy)
+  pure (x1, y1)
+
+iterateNM :: (Monad m) => Int -> (a -> m a) -> a -> m [a]
+iterateNM n f x0 = go n x0 id
+  where
+    go k x acc
+      | k > 0 = do
+        y <- f x
+        go (k - 1) y (acc . (y :))
+      | otherwise = pure (acc [])
+
+main :: IO ()
+main = do
+  let (x0, y0) = (0.1, 0.4)
+  -- pure haskell
+  putStrLn "pure haskell"
+  let f = pure . rosenbrock (1, 10)
+      df = pure . dRosenbrock (1, 10)
+  histH <- iterateNM 10 (step f df) (x0, y0)
+  traverse_ print histH
+
+  -- C
+  putStrLn "codegen C"
+  let g (x, y) = do
+        Output z <- hs_rosenbrockF (Input (Param 1 10) (XY (kliteral x) (kliteral y)))
+        pure (unsafeC z)
+      dg (x, y) = do
+        XY x' y' <- hs_dRosenbrockF (Input (Param 1 10) (XY (kliteral x) (kliteral y)))
+        pure (unsafeC x', unsafeC y')
+  histC <- iterateNM 10 (step g dg) (x0, y0)
+  traverse_ print histC
diff --git a/examples/separate-categorification/Main.hs b/examples/separate-categorification/Main.hs
index 80ea0d5..f0fdd80 100644
--- a/examples/separate-categorification/Main.hs
+++ b/examples/separate-categorification/Main.hs
@@ -7,4 +7,4 @@ import F (fCategorified)
 
 -- This generates /tmp/separate_categorification.c
 main :: IO ()
-main = writeCFiles "/tmp" "separate_categorification" fCategorified
+main = writeCFiles "." "separate_categorification" fCategorified