diff --git a/bench/Lambda.hs b/bench/Lambda.hs
new file mode 100644
index 0000000..edddc7f
--- /dev/null
+++ b/bench/Lambda.hs
@@ -0,0 +1,52 @@
+{-# LANGUAGE DeriveGeneric #-}
+{-# LANGUAGE TemplateHaskell #-}
+
+module Lambda (Lambda (..), DeBruijn (..), lambdaSampler) where
+
+import Control.DeepSeq
+import Control.Monad (replicateM)
+import Data.Boltzmann (
+  BoltzmannSampler (..),
+  Constructable ((<:>)),
+  LowerBound (MkLowerBound),
+  System (System, frequencies, meanSize, targetType, weights),
+  UpperBound (MkUpperBound),
+  evalIO,
+  mkBoltzmannSampler,
+  mkDefWeights,
+  rejectionSampler,
+ )
+import Data.Default (def)
+import GHC.Generics (Generic)
+import System.Random.SplitMix (SMGen)
+
+data DeBruijn
+  = Z
+  | S DeBruijn
+  deriving (Show, Generic)
+
+instance NFData DeBruijn
+
+data Lambda
+  = Index DeBruijn
+  | App Lambda Lambda
+  | Abs Lambda
+  deriving (Show, Generic)
+
+instance NFData Lambda
+
+mkBoltzmannSampler
+  System
+    { targetType = ''Lambda
+    , meanSize = 1000
+    , frequencies = def
+    , weights =
+        ('Index, 0)
+          <:> $(mkDefWeights ''Lambda)
+    }
+
+lambdaSampler :: Int -> IO [Lambda]
+lambdaSampler n =
+  evalIO $
+    replicateM n $
+      rejectionSampler @SMGen (MkLowerBound 800) (MkUpperBound 1200)
diff --git a/bench/Main.hs b/bench/Main.hs
new file mode 100644
index 0000000..3ed2f1c
--- /dev/null
+++ b/bench/Main.hs
@@ -0,0 +1,12 @@
+import Criterion.Main (bench, bgroup, defaultMain, nfIO)
+import Lambda (lambdaSampler)
+
+main :: IO ()
+main =
+  defaultMain
+    [ bgroup
+        "Boltzmann sampler for lambda terms of sizes [800..1200]"
+        [ bench "100 random terms" $ nfIO (lambdaSampler 100)
+        , bench "1000 random terms" $ nfIO (lambdaSampler 1000)
+        ]
+    ]
diff --git a/generic-boltzmann-brain.cabal b/generic-boltzmann-brain.cabal
index 1e756e1..1839263 100644
--- a/generic-boltzmann-brain.cabal
+++ b/generic-boltzmann-brain.cabal
@@ -120,3 +120,34 @@ test-suite generic-boltzmann-brain-test
     , transformers >=0.5.6
     , vector >=0.12.3.1
   default-language: Haskell2010
+
+benchmark generic-boltzmann-brain
+  type: exitcode-stdio-1.0
+  main-is: Main.hs
+  other-modules:
+      Lambda
+      Paths_generic_boltzmann_brain
+  hs-source-dirs:
+      bench
+  default-extensions:
+      NumericUnderscores LambdaCase BangPatterns DerivingVia FlexibleInstances UndecidableInstances TypeApplications ScopedTypeVariables Rank2Types
+  ghc-options: -O2 -Wall -Wcompat -Wmissing-export-lists -Wincomplete-record-updates -Wincomplete-uni-patterns -Wredundant-constraints -Wno-name-shadowing -fwarn-missing-signatures -ddump-splices
+  build-depends:
+      QuickCheck >=2.14.2
+    , base >=4.7 && <5
+    , containers >=0.6.4
+    , criterion >=1.5.12.0
+    , data-default >=0.7.1.1
+    , deepseq >=1.4.5.0
+    , generic-boltzmann-brain
+    , mtl >=2.2.2
+    , paganini-hs >=0.3.0.0
+    , random >=1.2.0
+    , splitmix >=0.1.0.4
+    , template-haskell >=2.17.0.0
+    , th-abstraction >=0.4.3.0
+    , th-lift >=0.8.2
+    , th-lift-instances >=0.1.18
+    , transformers >=0.5.6
+    , vector >=0.12.3.1
+  default-language: Haskell2010
diff --git a/hie.yaml b/hie.yaml
index f69bbf3..7c3eb35 100644
--- a/hie.yaml
+++ b/hie.yaml
@@ -1,6 +1,6 @@
 cradle:
   stack:
-    - path: "./src"
+    - path: "./api"
       component: "generic-boltzmann-brain:lib"
 
     - path: "./internal"
@@ -8,3 +8,9 @@ cradle:
 
     - path: "./test"
       component: "generic-boltzmann-brain:test:generic-boltzmann-brain-test"
+
+    - path: "./bench/Main.hs"
+      component: "generic-boltzmann-brain:bench:generic-boltzmann-brain"
+
+    - path: "./bench/Paths_generic_boltzmann_brain.hs"
+      component: "generic-boltzmann-brain:bench:generic-boltzmann-brain"
diff --git a/package.yaml b/package.yaml
index 25cbb22..a0e85c5 100644
--- a/package.yaml
+++ b/package.yaml
@@ -81,7 +81,38 @@ internal-libraries:
       UndecidableInstances
       TypeApplications
       ScopedTypeVariables
-     Rank2Types
+      Rank2Types
+
+benchmarks:
+  generic-boltzmann-brain:
+    source-dirs: bench
+    main:        Main.hs
+    ghc-options:
+    - -O2
+    - -Wall
+    - -Wcompat
+    - -Wmissing-export-lists
+    - -Wincomplete-record-updates
+    - -Wincomplete-uni-patterns
+    - -Wredundant-constraints
+    - -Wno-name-shadowing
+    - -fwarn-missing-signatures
+    - -ddump-splices
+    default-extensions:
+      NumericUnderscores
+      LambdaCase
+      BangPatterns
+      DerivingVia
+      FlexibleInstances
+      UndecidableInstances
+      TypeApplications
+      ScopedTypeVariables
+      Rank2Types
+    dependencies:
+    - generic-boltzmann-brain
+    - criterion >= 1.5.12.0
+    - deepseq >= 1.4.5.0
+    - QuickCheck >= 2.14.2
 
 tests:
   generic-boltzmann-brain-test: