diff --git a/ChangeLog.md b/ChangeLog.md
new file mode 100644
--- /dev/null
+++ b/ChangeLog.md
@@ -0,0 +1,7 @@
+# Changelog for homotuple
+
+## 0.1.0.0
+
+2019.10.10
+
+Release.
diff --git a/LICENSE b/LICENSE
new file mode 100644
--- /dev/null
+++ b/LICENSE
@@ -0,0 +1,13 @@
+Copyright 2019 Kazuki Okamoto
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+  http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
diff --git a/README.md b/README.md
new file mode 100644
--- /dev/null
+++ b/README.md
@@ -0,0 +1,1 @@
+# homotuple
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/homotuple.cabal b/homotuple.cabal
new file mode 100644
--- /dev/null
+++ b/homotuple.cabal
@@ -0,0 +1,48 @@
+cabal-version: 1.12
+
+-- This file has been generated from package.yaml by hpack version 0.31.1.
+--
+-- see: https://github.com/sol/hpack
+--
+-- hash: bf3e190ee92c45cf9f906b2ac73da62207735e115f856db4fc9fe116bdd7f963
+
+name:           homotuple
+version:        0.1.0.0
+synopsis:       Homotuple, all whose elements are the same type
+description:    Homotuple, all whose elements are the same type
+category:       Data
+homepage:       https://github.com/kakkun61/homotuple#readme
+bug-reports:    https://github.com/kakkun61/homotuple/issues
+author:         Kazuki Okamoto
+maintainer:     kazuki.okamoto@kakkun61.com
+copyright:      2019 Kazuki Okamoto
+license:        Apache
+license-file:   LICENSE
+build-type:     Simple
+extra-source-files:
+    README.md
+    ChangeLog.md
+
+source-repository head
+  type: git
+  location: https://github.com/kakkun61/homotuple
+
+library
+  exposed-modules:
+      Data.Tuple.Homotuple
+      Data.Tuple.Homotuple.Identity
+      Data.Tuple.Homotuple.OneTuple
+      Data.Tuple.Homotuple.Only
+  other-modules:
+      Paths_homotuple
+  hs-source-dirs:
+      src
+  ghc-options: -Wall -Wcompat -Wincomplete-uni-patterns -Wincomplete-record-updates -Wmonomorphism-restriction -Wmissing-exported-signatures -Wmissing-export-lists -Wmissing-home-modules -Wmissing-import-lists -Widentities -Wredundant-constraints -Wpartial-fields -Wno-name-shadowing
+  build-depends:
+      OneTuple >=0.2 && <0.3
+    , Only >=0.1 && <0.2
+    , base >=4.12 && <4.13
+    , single-tuple >=0.1 && <0.2
+  if impl(ghc >= 8.6.1)
+    default-extensions: NoStarIsType
+  default-language: Haskell2010
diff --git a/src/Data/Tuple/Homotuple.hs b/src/Data/Tuple/Homotuple.hs
new file mode 100644
--- /dev/null
+++ b/src/Data/Tuple/Homotuple.hs
@@ -0,0 +1,349 @@
+{-# LANGUAGE ConstraintKinds        #-}
+{-# LANGUAGE DataKinds              #-}
+{-# LANGUAGE FlexibleContexts       #-}
+{-# LANGUAGE FlexibleInstances      #-}
+{-# LANGUAGE PatternSynonyms        #-}
+{-# LANGUAGE ScopedTypeVariables    #-}
+{-# LANGUAGE Trustworthy            #-}
+{-# LANGUAGE TypeFamilies           #-}
+{-# LANGUAGE TypeFamilyDependencies #-}
+{-# LANGUAGE TypeOperators          #-}
+
+{-# OPTIONS_GHC -Wno-orphans #-}
+
+{-# OPTIONS_HADDOCK show-extensions #-}
+
+-- |
+-- Copyright   :  Kazuki Okamoto
+-- License     :  see LICENSE
+-- Maintainer  :  kazuki.okamoto@kakkun61.com
+-- Stability   :  experimental
+-- Portability :  GHC
+--
+-- Homotuples, whoes items are the same type or which are lists with type-level length.
+
+module Data.Tuple.Homotuple
+  ( Homotuple
+    -- * List-like
+  , replicate
+    -- * Functor-like
+  , (<$>)
+    -- * Applicative-like
+  , (<*>)
+  , pure
+    -- * Monad-like
+  , (>>=)
+    -- * Semigoupe-like
+  , (<>)
+    -- * Monoid-like
+  , pattern Empty
+    -- * Utility constraints
+  , IsHomolisttuple
+  , IsHomotupleItem
+    -- * For implementers
+  , errorLengthMismatch
+  ) where
+
+import Prelude (Num (fromInteger), error, ($), (.))
+
+import qualified Control.Applicative as A
+import qualified Control.Monad       as M
+import           Data.Kind           (Type)
+import qualified Data.List           as L
+import           Data.Proxy          (Proxy (Proxy))
+import qualified Data.Semigroup      as S
+import           Data.Tuple.Single   (Single (wrap))
+import           GHC.Exts            (IsList (Item, fromList, toList))
+import           GHC.Stack           (HasCallStack)
+import           GHC.TypeLits        (type (*), type (+), KnownNat, Nat, natVal)
+
+type family Homotuple (n :: Nat) (a :: Type) = (t :: Type) | t -> n
+
+type instance Homotuple 0 a = Proxy a
+
+type instance Homotuple 2 a = (a, a)
+
+type instance Homotuple 3 a = (a, a, a)
+
+type instance Homotuple 4 a = (a, a, a, a)
+
+type instance Homotuple 5 a = (a, a, a, a, a)
+
+type instance Homotuple 6 a = (a, a, a, a, a, a)
+
+type instance Homotuple 7 a = (a, a, a, a, a, a, a)
+
+type instance Homotuple 8 a = (a, a, a, a, a, a, a, a)
+
+type instance Homotuple 9 a = (a, a, a, a, a, a, a, a, a)
+
+type instance Homotuple 10 a = (a, a, a, a, a, a, a, a, a, a)
+
+type instance Homotuple 11 a = (a, a, a, a, a, a, a, a, a, a, a)
+
+type instance Homotuple 12 a = (a, a, a, a, a, a, a, a, a, a, a, a)
+
+type instance Homotuple 13 a = (a, a, a, a, a, a, a, a, a, a, a, a, a)
+
+type instance Homotuple 14 a = (a, a, a, a, a, a, a, a, a, a, a, a, a, a)
+
+type instance Homotuple 15 a = (a, a, a, a, a, a, a, a, a, a, a, a, a, a, a)
+
+type instance Homotuple 16 a = (a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a)
+
+type instance Homotuple 17 a = (a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a)
+
+type instance Homotuple 18 a = (a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a)
+
+type instance Homotuple 19 a = (a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a)
+
+type instance Homotuple 20 a = (a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a)
+
+type instance Homotuple 21 a = (a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a)
+
+type instance Homotuple 22 a = (a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a)
+
+type instance Homotuple 23 a = (a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a)
+
+type instance Homotuple 24 a = (a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a)
+
+type instance Homotuple 25 a = (a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a)
+
+type instance Homotuple 26 a = (a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a)
+
+type instance Homotuple 27 a = (a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a)
+
+type instance Homotuple 28 a = (a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a)
+
+type instance Homotuple 29 a = (a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a)
+
+type instance Homotuple 30 a = (a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a)
+
+type instance Homotuple 31 a = (a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a)
+
+type instance Homotuple 32 a = (a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a)
+
+type instance Homotuple 33 a = (a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a)
+
+type instance Homotuple 34 a = (a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a)
+
+type instance Homotuple 35 a = (a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a)
+
+type instance Homotuple 36 a = (a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a)
+
+type instance Homotuple 37 a = (a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a)
+
+type instance Homotuple 38 a = (a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a)
+
+type instance Homotuple 39 a = (a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a)
+
+type instance Homotuple 40 a = (a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a)
+
+type instance Homotuple 41 a = (a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a)
+
+type instance Homotuple 42 a = (a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a)
+
+type instance Homotuple 43 a = (a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a)
+
+type instance Homotuple 44 a = (a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a)
+
+type instance Homotuple 45 a = (a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a)
+
+type instance Homotuple 46 a = (a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a)
+
+type instance Homotuple 47 a = (a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a)
+
+type instance Homotuple 48 a = (a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a)
+
+type instance Homotuple 49 a = (a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a)
+
+type instance Homotuple 50 a = (a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a)
+
+type instance Homotuple 51 a = (a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a)
+
+type instance Homotuple 52 a = (a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a)
+
+type instance Homotuple 53 a = (a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a)
+
+type instance Homotuple 54 a = (a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a)
+
+type instance Homotuple 55 a = (a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a)
+
+type instance Homotuple 56 a = (a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a)
+
+type instance Homotuple 57 a = (a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a)
+
+type instance Homotuple 58 a = (a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a)
+
+type instance Homotuple 59 a = (a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a)
+
+type instance Homotuple 60 a = (a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a)
+
+type instance Homotuple 61 a = (a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a)
+
+type instance Homotuple 62 a = (a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a, a)
+
+instance IsList (Proxy a) where
+  type Item (Proxy a) = a
+  fromList [] = Proxy
+  fromList _  = errorLengthMismatch
+  toList _ = []
+
+instance IsList (a, a) where
+  type Item (a, a) = a
+  fromList [a, b] = (a, b)
+  fromList _      = errorLengthMismatch
+  toList (a, b) = [a, b]
+
+instance IsList (a, a, a) where
+  type Item (a, a, a) = a
+  fromList [a, b, c] = (a, b, c)
+  fromList _         = errorLengthMismatch
+  toList (a, b, c) = [a, b, c]
+
+instance IsList (a, a, a, a) where
+  type Item (a, a, a, a) = a
+  fromList [a, b, c, d] = (a, b, c, d)
+  fromList _            = errorLengthMismatch
+  toList (a, b, c, d) = [a, b, c, d]
+
+instance IsList (a, a, a, a, a) where
+  type Item (a, a, a, a, a) = a
+  fromList [a, b, c, d, e] = (a, b, c, d, e)
+  fromList _               = errorLengthMismatch
+  toList (a, b, c, d, e) = [a, b, c, d, e]
+
+instance IsList (a, a, a, a, a, a) where
+  type Item (a, a, a, a, a, a) = a
+  fromList [a, b, c, d, e, f] = (a, b, c, d, e, f)
+  fromList _                  = errorLengthMismatch
+  toList (a, b, c, d, e, f) = [a, b, c, d, e, f]
+
+instance IsList (a, a, a, a, a, a, a) where
+  type Item (a, a, a, a, a, a, a) = a
+  fromList [a, b, c, d, e, f, g] = (a, b, c, d, e, f, g)
+  fromList _                     = errorLengthMismatch
+  toList (a, b, c, d, e, f, g) = [a, b, c, d, e, f, g]
+
+instance IsList (a, a, a, a, a, a, a, a) where
+  type Item (a, a, a, a, a, a, a, a) = a
+  fromList [a, b, c, d, e, f, g, h] = (a, b, c, d, e, f, g, h)
+  fromList _                        = errorLengthMismatch
+  toList (a, b, c, d, e, f, g, h) = [a, b, c, d, e, f, g, h]
+
+instance IsList (a, a, a, a, a, a, a, a, a) where
+  type Item (a, a, a, a, a, a, a, a, a) = a
+  fromList [a, b, c, d, e, f, g, h, i] = (a, b, c, d, e, f, g, h, i)
+  fromList _                           = errorLengthMismatch
+  toList (a, b, c, d, e, f, g, h, i) = [a, b, c, d, e, f, g, h, i]
+
+instance IsList (a, a, a, a, a, a, a, a, a, a) where
+  type Item (a, a, a, a, a, a, a, a, a, a) = a
+  fromList [a, b, c, d, e, f, g, h, i, j] = (a, b, c, d, e, f, g, h, i, j)
+  fromList _                              = errorLengthMismatch
+  toList (a, b, c, d, e, f, g, h, i, j) = [a, b, c, d, e, f, g, h, i, j]
+
+instance IsList (a, a, a, a, a, a, a, a, a, a, a) where
+  type Item (a, a, a, a, a, a, a, a, a, a, a) = a
+  fromList [a, b, c, d, e, f, g, h, i, j, k] = (a, b, c, d, e, f, g, h, i, j, k)
+  fromList _                                 = errorLengthMismatch
+  toList (a, b, c, d, e, f, g, h, i, j, k) = [a, b, c, d, e, f, g, h, i, j, k]
+
+instance IsList (a, a, a, a, a, a, a, a, a, a, a, a) where
+  type Item (a, a, a, a, a, a, a, a, a, a, a, a) = a
+  fromList [a, b, c, d, e, f, g, h, i, j, k, l] = (a, b, c, d, e, f, g, h, i, j, k, l)
+  fromList _                                    = errorLengthMismatch
+  toList (a, b, c, d, e, f, g, h, i, j, k, l) = [a, b, c, d, e, f, g, h, i, j, k, l]
+
+instance IsList (a, a, a, a, a, a, a, a, a, a, a, a, a) where
+  type Item (a, a, a, a, a, a, a, a, a, a, a, a, a) = a
+  fromList [a, b, c, d, e, f, g, h, i, j, k, l, m] = (a, b, c, d, e, f, g, h, i, j, k, l, m)
+  fromList _                                       = errorLengthMismatch
+  toList (a, b, c, d, e, f, g, h, i, j, k, l, m) = [a, b, c, d, e, f, g, h, i, j, k, l, m]
+
+instance IsList (a, a, a, a, a, a, a, a, a, a, a, a, a, a) where
+  type Item (a, a, a, a, a, a, a, a, a, a, a, a, a, a) = a
+  fromList [a, b, c, d, e, f, g, h, i, j, k, l, m, n] = (a, b, c, d, e, f, g, h, i, j, k, l, m, n)
+  fromList _                                          = errorLengthMismatch
+  toList (a, b, c, d, e, f, g, h, i, j, k, l, m, n) = [a, b, c, d, e, f, g, h, i, j, k, l, m, n]
+
+instance IsList (a, a, a, a, a, a, a, a, a, a, a, a, a, a, a) where
+  type Item (a, a, a, a, a, a, a, a, a, a, a, a, a, a, a) = a
+  fromList [a, b, c, d, e, f, g, h, i, j, k, l, m, n, o] = (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o)
+  fromList _                                             = errorLengthMismatch
+  toList (a, b, c, d, e, f, g, h, i, j, k, l, m, n, o) = [a, b, c, d, e, f, g, h, i, j, k, l, m, n, o]
+
+errorLengthMismatch :: HasCallStack => a
+errorLengthMismatch = error "length mismatch"
+
+-- Utility constraints
+
+type IsHomolisttuple (n :: Nat) a = IsList (Homotuple n a)
+type IsHomotupleItem (n :: Nat) a = a ~ Item (Homotuple n a)
+
+-- List-like
+
+replicate :: forall (n :: Nat) a. (IsHomolisttuple n a, IsHomotupleItem n a, KnownNat n) => a -> Homotuple n a
+replicate = fromList . L.replicate (fromInteger $ natVal (Proxy :: Proxy n))
+
+-- Functor-like
+
+(<$>)
+  :: ( IsHomolisttuple n a
+     , IsHomolisttuple n b
+     , IsHomotupleItem n a
+     , IsHomotupleItem n b
+     )
+  => (a -> b) -> Homotuple n a -> Homotuple n b
+f <$> t = fromList $ L.map f $ toList t
+
+-- Applicative-like
+
+(<*>)
+  :: ( IsHomolisttuple n0 (a -> b)
+     , IsHomolisttuple n1 a
+     , IsHomolisttuple (n0 * n1) b
+     , IsHomotupleItem n0 (a -> b)
+     , IsHomotupleItem n1 a
+     , IsHomotupleItem (n0 * n1) b
+     )
+  => Homotuple n0 (a -> b) -> Homotuple n1 a -> Homotuple (n0 * n1) b
+f <*> t = fromList $ toList f A.<*> toList t
+
+pure :: Single c => a -> c a
+pure = wrap
+
+-- Monad-like
+
+(>>=)
+  :: ( IsHomolisttuple n0 a
+     , IsHomolisttuple n1 b
+     , IsHomolisttuple (n0 * n1) b
+     , IsHomotupleItem n0 a
+     , IsHomotupleItem n1 b
+     , IsHomotupleItem (n0 * n1) b
+     )
+  => Homotuple n0 a -> (a -> Homotuple n1 b) -> Homotuple (n0 * n1) b
+m >>= f = fromList $ toList m M.>>= (toList . f)
+
+-- Semigroup-like
+
+(<>)
+  :: ( IsHomolisttuple n0 a
+     , IsHomolisttuple n1 a
+     , IsHomolisttuple (n0 + n1) a
+     , IsHomotupleItem n0 a
+     , IsHomotupleItem n1 a
+     , IsHomotupleItem (n0 + n1) a
+     )
+  => Homotuple n0 a
+  -> Homotuple n1 a
+  -> Homotuple (n0 + n1) a
+a <> b = fromList $ toList a S.<> toList b
+
+infixr 6 <>
+
+-- Monoid-like
+
+pattern Empty :: Homotuple 0 a
+pattern Empty = Proxy
diff --git a/src/Data/Tuple/Homotuple/Identity.hs b/src/Data/Tuple/Homotuple/Identity.hs
new file mode 100644
--- /dev/null
+++ b/src/Data/Tuple/Homotuple/Identity.hs
@@ -0,0 +1,30 @@
+{-# LANGUAGE DataKinds    #-}
+{-# LANGUAGE Trustworthy  #-}
+{-# LANGUAGE TypeFamilies #-}
+
+{-# OPTIONS_GHC -Wno-orphans #-}
+
+{-# OPTIONS_HADDOCK show-extensions #-}
+
+-- |
+-- Copyright   :  Kazuki Okamoto
+-- License     :  see LICENSE
+-- Maintainer  :  kazuki.okamoto@kakkun61.com
+-- Stability   :  experimental
+-- Portability :  GHC
+--
+-- Single homotuples.
+
+module Data.Tuple.Homotuple.Identity () where
+
+import Data.Functor.Identity (Identity (Identity))
+import Data.Tuple.Homotuple  (Homotuple, errorLengthMismatch)
+import GHC.Exts              (IsList (Item, fromList, toList))
+
+type instance Homotuple 1 a = Identity a
+
+instance IsList (Identity a) where
+  type Item (Identity a) = a
+  fromList [a] = Identity a
+  fromList _   = errorLengthMismatch
+  toList (Identity a) = [a]
diff --git a/src/Data/Tuple/Homotuple/OneTuple.hs b/src/Data/Tuple/Homotuple/OneTuple.hs
new file mode 100644
--- /dev/null
+++ b/src/Data/Tuple/Homotuple/OneTuple.hs
@@ -0,0 +1,30 @@
+{-# LANGUAGE DataKinds    #-}
+{-# LANGUAGE Trustworthy  #-}
+{-# LANGUAGE TypeFamilies #-}
+
+{-# OPTIONS_GHC -Wno-orphans #-}
+
+{-# OPTIONS_HADDOCK show-extensions #-}
+
+-- |
+-- Copyright   :  Kazuki Okamoto
+-- License     :  see LICENSE
+-- Maintainer  :  kazuki.okamoto@kakkun61.com
+-- Stability   :  experimental
+-- Portability :  GHC
+--
+-- Single homotuples.
+
+module Data.Tuple.Homotuple.OneTuple () where
+
+import Data.Tuple.Homotuple (Homotuple, errorLengthMismatch)
+import Data.Tuple.OneTuple  (OneTuple (OneTuple))
+import GHC.Exts             (IsList (Item, fromList, toList))
+
+type instance Homotuple 1 a = OneTuple a
+
+instance IsList (OneTuple a) where
+  type Item (OneTuple a) = a
+  fromList [a] = OneTuple a
+  fromList _   = errorLengthMismatch
+  toList (OneTuple a) = [a]
diff --git a/src/Data/Tuple/Homotuple/Only.hs b/src/Data/Tuple/Homotuple/Only.hs
new file mode 100644
--- /dev/null
+++ b/src/Data/Tuple/Homotuple/Only.hs
@@ -0,0 +1,30 @@
+{-# LANGUAGE DataKinds    #-}
+{-# LANGUAGE Trustworthy  #-}
+{-# LANGUAGE TypeFamilies #-}
+
+{-# OPTIONS_GHC -Wno-orphans #-}
+
+{-# OPTIONS_HADDOCK show-extensions #-}
+
+-- |
+-- Copyright   :  Kazuki Okamoto
+-- License     :  see LICENSE
+-- Maintainer  :  kazuki.okamoto@kakkun61.com
+-- Stability   :  experimental
+-- Portability :  GHC
+--
+-- Single homotuples.
+
+module Data.Tuple.Homotuple.Only () where
+
+import Data.Tuple.Homotuple (Homotuple, errorLengthMismatch)
+import Data.Tuple.Only      (Only (Only))
+import GHC.Exts             (IsList (Item, fromList, toList))
+
+type instance Homotuple 1 a = Only a
+
+instance IsList (Only a) where
+  type Item (Only a) = a
+  fromList [a] = Only a
+  fromList _   = errorLengthMismatch
+  toList (Only a) = [a]