diff --git a/CHANGELOG.md b/CHANGELOG.md
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,6 +1,17 @@
 Changelog
 =========
 
+Version 0.2.1.0
+---------------
+
+*Jan 20, 2018*
+
+<https://github.com/mstksg/type-combinators-singletons/releases/tag/v0.2.1.0>
+
+*   Added `singSome`/`someSing` and `singWit1`/`wit1Sing`, to convert between
+    the *singletons* types `SomeSing` and `SingInstance` and their more generic
+    representations in *type-combinators*, `Some Sing` and `Wit1 Sing`.
+
 Version 0.2.0.0
 ---------------
 
diff --git a/src/Data/Type/Combinator/Singletons.hs b/src/Data/Type/Combinator/Singletons.hs
--- a/src/Data/Type/Combinator/Singletons.hs
+++ b/src/Data/Type/Combinator/Singletons.hs
@@ -29,6 +29,8 @@
   -- * Conversion functions
     TC(..)
   , singLength
+  , singSome, someSing
+  , singWit1, wit1Sing
   -- * Orphan singleton instance for 'N'
   , Sing(SZ, SS), SN, ZSym0, SSym0, SSym1
   ) where
@@ -139,4 +141,24 @@
 singLength = \case
     SNil         -> LZ
     _ `SCons` xs -> LS (singLength xs)
+
+-- | Convert @'SomeSing' k@ from /singletons/ into the more generic
+-- representation @'Some' 'Sing'@, from /type-combinators/.
+singSome :: SomeSing k -> Some (Sing :: k -> Type)
+singSome (SomeSing s) = Some s
+
+-- | Convert the generic representation @'Some' 'Sing'@ from
+-- /type-combinatprs/ to @'SomeSing' k@, from /singletons/.
+someSing :: Some (Sing :: k -> Type) -> SomeSing k
+someSing ss = some ss SomeSing
+
+-- | Convert a @'SingInstance' a@ from /singletons/ into the more generic
+-- representation @'Wit1' 'SingI' a@.
+singWit1 :: SingInstance a -> Wit1 SingI a
+singWit1 SingInstance = Wit1
+
+-- | Convert the generic representation @'Wit1' 'SIngI' a@ from
+-- /type-combinators/ to @'SingInstance' a@ from /singletons/.
+wit1Sing :: Wit1 SingI a -> SingInstance a
+wit1Sing Wit1 = SingInstance
 
diff --git a/type-combinators-singletons.cabal b/type-combinators-singletons.cabal
--- a/type-combinators-singletons.cabal
+++ b/type-combinators-singletons.cabal
@@ -1,5 +1,5 @@
 name:                type-combinators-singletons
-version:             0.2.0.0
+version:             0.2.1.0
 synopsis:            Interop between /type-combinators/ and /singletons/.
 description:         Conversions between datatypes in /type-combinators/ and
                      singletons from /singletons/ and orphan instances.
@@ -25,15 +25,6 @@
                      , singletons
   default-language:    Haskell2010
   ghc-options:         -Wall
-
--- test-suite type-combinators-singletons-test
---   type:                exitcode-stdio-1.0
---   hs-source-dirs:      test
---   main-is:             Spec.hs
---   build-depends:       base
---                      , type-combinators-singletons
---   ghc-options:         -threaded -rtsopts -with-rtsopts=-N
---   default-language:    Haskell2010
 
 source-repository head
   type:     git