diff --git a/CHANGELOG.md b/CHANGELOG.md
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--- /dev/null
+++ b/CHANGELOG.md
@@ -0,0 +1,3 @@
+## 0.1
+
+* First version. Released on an unsuspecting world.
diff --git a/LICENSE b/LICENSE
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--- /dev/null
+++ b/LICENSE
@@ -0,0 +1,30 @@
+Copyright (c) 2023, Oleg Grenrus
+
+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 Oleg Grenrus 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/defun-bool.cabal b/defun-bool.cabal
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--- /dev/null
+++ b/defun-bool.cabal
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+cabal-version:   2.4
+name:            defun-bool
+version:         0.1
+license:         BSD-3-Clause
+license-file:    LICENSE
+author:          Oleg Grenrus <oleg.grenrus@iki.fi>
+maintainer:      Oleg Grenrus <oleg.grenrus@iki.fi>
+category:        Data
+build-type:      Simple
+extra-doc-files: CHANGELOG.md
+tested-with:     GHC ==9.2.8 || ==9.4.8 || ==9.6.3 || ==9.8.1
+synopsis:        Defunctionalization helpers: booleans
+description:
+  This package provides type and term definitions for boolean type families
+  in "Data.Type.Bool" (in @base@) using @SBool@ type from @singleton-bool@ package.
+
+source-repository head
+  type:     git
+  location: https://github.com/phadej/defun.git
+  subdir:   defun-bool
+
+common language
+  default-language:   Haskell2010
+  default-extensions:
+    DataKinds
+    EmptyCase
+    GADTs
+    KindSignatures
+    NoImplicitPrelude
+    PatternSynonyms
+    PolyKinds
+    RankNTypes
+    ScopedTypeVariables
+    StandaloneKindSignatures
+    TypeApplications
+    TypeFamilies
+    TypeOperators
+    UndecidableInstances
+    ViewPatterns
+
+library
+  import:            language
+  hs-source-dirs:    src
+  exposed-modules:   SBool.DeFun
+  build-depends:
+    , base            ^>=4.16.3.0 || ^>=4.17.2.0 || ^>=4.18.0.0 || ^>=4.19.0.0
+    , defun-core      ^>=0.1
+    , singleton-bool  ^>=0.1.7
+
+  x-docspec-options: -XDataKinds -XGADTs -XStandaloneDeriving
diff --git a/src/SBool/DeFun.hs b/src/SBool/DeFun.hs
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--- /dev/null
+++ b/src/SBool/DeFun.hs
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+{-# LANGUAGE Trustworthy #-}
+-- | Boolean functions.
+--
+-- Type families are defined in "Data.Type.Bool" module in @base@ package.
+-- Term implementation use 'SBool' from @singleton-bool@ package.
+--
+module SBool.DeFun (
+    -- * Logical and
+    LAnd, LAndSym, LAndSym1,
+    land, landSym, landSym1,
+    -- * Logical or
+    LOr, LOrSym, LOrSym1,
+    lor, lorSym, lorSym1,
+    -- * Logical not
+    Not, NotSym,
+    not, notSym,
+) where
+
+import Data.Singletons.Bool (SBool (..), sboolAnd, sboolNot, sboolOr)
+
+import DeFun.Bool
+import DeFun.Core
+
+-------------------------------------------------------------------------------
+-- LAnd
+-------------------------------------------------------------------------------
+
+land :: SBool x -> SBool y -> SBool (LAnd x y)
+land = sboolAnd
+
+landSym1 :: SBool x -> Lam SBool SBool (LAndSym1 x)
+landSym1 x = Lam (land x)
+
+landSym :: Lam2 SBool SBool SBool LAndSym
+landSym = Lam landSym1
+
+-------------------------------------------------------------------------------
+-- LOr
+-------------------------------------------------------------------------------
+
+lor :: SBool x -> SBool y -> SBool (LOr x y)
+lor = sboolOr
+
+lorSym1 :: SBool x -> Lam SBool SBool (LOrSym1 x)
+lorSym1 x = Lam (lor x)
+
+lorSym :: Lam2 SBool SBool SBool LOrSym
+lorSym = Lam lorSym1
+
+-------------------------------------------------------------------------------
+-- Not
+-------------------------------------------------------------------------------
+
+not :: SBool x -> SBool (Not x)
+not = sboolNot
+
+notSym :: Lam SBool SBool NotSym
+notSym = Lam not