diff --git a/preamble.cabal b/preamble.cabal
--- a/preamble.cabal
+++ b/preamble.cabal
@@ -1,5 +1,5 @@
 name:                  preamble
-version:               0.0.12
+version:               0.0.13
 synopsis:              Yet another prelude.
 description:           A prelude built on basic-prelude.
 homepage:              https://github.com/swift-nav/preamble
@@ -23,6 +23,7 @@
                      , Preamble.Types
                      , Preamble.Types.Alias
                      , Preamble.Types.Ctx
+                     , Preamble.Types.Orphan
                      , Preamble.Types.Trans
   default-language:    Haskell2010
   ghc-options:         -Wall
diff --git a/src/Preamble/Types/Orphan.hs b/src/Preamble/Types/Orphan.hs
new file mode 100644
--- /dev/null
+++ b/src/Preamble/Types/Orphan.hs
@@ -0,0 +1,17 @@
+{-# OPTIONS  -fno-warn-orphans #-}
+{-# LANGUAGE NoImplicitPrelude #-}
+
+-- | Various orphans.
+--
+module Preamble.Types.Orphan where
+
+import Data.Aeson
+import Data.UUID
+import Preamble.Prelude
+
+instance ToJSON UUID where
+  toJSON = toJSON . toText
+
+instance FromJSON UUID where
+  parseJSON (String s) = maybe mzero return $ fromText s
+  parseJSON _ = mzero