diff --git a/CHANGELOG.md b/CHANGELOG.md
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+# Changelog
+
+All notable changes to the constrained-some library will be documented in this
+file.
+
+The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
+and this project adheres to [PVP versioning](https://pvp.haskell.org/).
+
+## Initial release: v0.0.1 _(2024-11-27)_
+
+### Added
+- Existentials `Somes` and `Somes1`
diff --git a/LICENSE b/LICENSE
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+++ b/LICENSE
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+Copyright (c) 2024 Julian Bruder
+
+Permission is hereby granted, free of charge, to any person obtaining
+a copy of this software and associated documentation files (the
+"Software"), to deal in the Software without restriction, including
+without limitation the rights to use, copy, modify, merge, publish,
+distribute, sublicense, and/or sell copies of the Software, and to
+permit persons to whom the Software is furnished to do so, subject to
+the following conditions:
+
+The above copyright notice and this permission notice shall be included
+in all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
diff --git a/README.md b/README.md
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--- /dev/null
+++ b/README.md
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+[![Hackage](https://img.shields.io/hackage/v/constrained-some.svg)](https://hackage.haskell.org/package/constrained-some) ![Static Badge](https://img.shields.io/badge/Lang-Haskell2010-blue) [![Haskell-CI](https://github.com/bruderj15/constrained-some/actions/workflows/haskell-ci.yml/badge.svg)](https://github.com/bruderj15/constrained-some/actions/workflows/haskell-ci.yml) [![License: GPL v3](https://img.shields.io/badge/License-MIT-blue.svg)](https://mit-license.org/)
+
+# constrained-some
+
+This library provides utilities for working with existential types and type-level constraints.
+It allows you to enforce multiple constraints on polymorphic types and containers complementing `some`.
+
+## Core
+
+- **Existential Types**: `Somes` and `Somes1` provide existential wrappers for types with multiple constraints.
+- **Convenient Aliases**: Simplified types `Some` and `Some1` for scenarios where just one constraint is needed.
+
+## Usage
+
+```haskell
+import Data.Some.Constraint
+
+someShowableOrd :: Somes '[Show, Ord]
+someShowableOrd = Some (mempty :: [Double])
+
+someNumFunctor :: Some1 Functor Num
+someNumFunctor = Some1 $ [1, 2, 3 :: Int]
+```
+
+## Contact information
+Contributions, critics and bug reports are welcome!
+
+Please feel free to contact me through GitHub.
diff --git a/constrained-some.cabal b/constrained-some.cabal
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+++ b/constrained-some.cabal
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+cabal-version:      3.0
+name:               constrained-some
+version:            0.1.0.0
+synopsis:           Existential type that can be constrained
+description:        This library provides utilities for working with existential types and type-level constraints.
+  It allows you to enforce multiple constraints on polymorphic types and containers complementing the package some.
+homepage:           https://github.com/bruderj15/constrained-some
+bug-reports:        https://github.com/bruderj15/constrained-some/issues
+license:            MIT
+license-file:       LICENSE
+author:             Julian Bruder
+maintainer:         julian.bruder@outlook.com
+copyright:          © 2024 Julian Bruder
+category:           Data, Dependent Types
+build-type:         Simple
+extra-source-files: README.md
+extra-doc-files:    CHANGELOG.md
+tested-with:
+  GHC ==8.10.4
+   || ==9.0.2
+   || ==9.2.8
+   || ==9.4.8
+   || ==9.6.5
+   || ==9.8.2
+   || ==9.10.1
+
+common warnings
+    ghc-options: -Wall
+
+library
+    import:           warnings
+    exposed-modules:  Data.Some.Constraint
+    build-depends:    base >=4.12 && <4.21
+    hs-source-dirs:   src
+    default-language: Haskell2010
+
+test-suite constrained-some-test
+    import:           warnings
+    default-language: Haskell2010
+    type:             exitcode-stdio-1.0
+    hs-source-dirs:   test
+    main-is:          Main.hs
+    build-depends:
+        base >=4.12 && <4.21,
+        constrained-some
diff --git a/src/Data/Some/Constraint.hs b/src/Data/Some/Constraint.hs
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+++ b/src/Data/Some/Constraint.hs
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+{-# LANGUAGE DataKinds #-}
+{-# LANGUAGE PolyKinds #-}
+{-# LANGUAGE TypeFamilies #-}
+{-# LANGUAGE QuantifiedConstraints #-}
+{-# LANGUAGE StandaloneKindSignatures #-}
+{-# LANGUAGE TypeOperators #-}
+{-# LANGUAGE GADTs #-}
+
+module Data.Some.Constraint where
+
+import Data.Kind
+
+-- | AllC ensures that a list of 'Constraint's is applied to a poly-kinded 'Type' @k@.
+type AllC :: forall k. [k -> Constraint] -> k -> Constraint
+type family AllC cs k :: Constraint where
+  AllC '[]       k = ()
+  AllC (c ': cs) k = (c k, AllC cs k)
+
+-- | Existential with 'Constraint's.
+--
+-- ==== __Example__
+--
+-- @
+-- someShowableOrd :: 'Somes' '['Show', 'Ord']
+-- someShowableOrd = 'Some' ('mempty' :: ['Double'])
+-- @
+data Somes cs where
+  Some :: forall
+    (cs :: [Type -> Constraint])
+    (a :: Type).
+    AllC cs a => a -> Somes cs
+
+-- | Alias for 'Somes' with just one 'Constraint'.
+type Some c = Somes '[c]
+
+-- | Existential for containers with 'Constraint's.
+--
+-- ==== __Example__
+--
+-- @
+-- someNumFunctor :: 'Somes1' '['Functor'] '['Num']
+-- someNumFunctor = 'Some1' $ [1, 2, 3 :: 'Int']
+-- @
+data Somes1 csf csa where
+  Some1 :: forall
+    k
+    (csf :: [(k -> Type) -> Constraint])
+    (csa :: [k -> Constraint])
+    (f :: k -> Type)
+    (a :: k).
+    (AllC csf f, AllC csa a) => f a -> Somes1 csf csa
+
+-- | Alias for 'Somes1' with just one 'Constraint'.
+type Some1 ca cf = Somes1 '[ca] '[cf]
diff --git a/test/Main.hs b/test/Main.hs
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+++ b/test/Main.hs
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+module Main (main) where
+
+main :: IO ()
+main = putStrLn "Test suite not yet implemented."