refactor: reimplement Tagged, drop dependency

keter.cabal

@@ -64,7 +64,6 @@ library
       random >=1.2.1 && <1.3,
       regex-tdfa >=1.3.1 && <1.4,
       stm >=2.5.0 && <2.6,
-      tagged >= 0.1.0 && <1.0,
       tar >=0.5.1 && <0.6,
       template-haskell >=2.17.0 && <3.0,
       text >=1.2.5 && <3.0,

src/Keter/Common.hs

@@ -1,4 +1,6 @@
 {-# LANGUAGE DeriveDataTypeable #-}
+{-# LANGUAGE DeriveFunctor #-}
+{-# LANGUAGE PolyKinds #-}
 {-# LANGUAGE OverloadedStrings  #-}
 {-# LANGUAGE TemplateHaskell    #-}
 {-# LANGUAGE TypeFamilies       #-}
@@ -114,3 +116,8 @@ instance FromJSON SSLConfig where
                             return $ SSL cert chainCerts key
                         _ -> return SSLFalse -- fail "Must provide both certificate and key files"
                     ) v
+
+-- | A helper to attach arbitrary "phantom type" to a value type.
+-- Reimplemented minimally from the `tagged` package to avoid a dependency.
+newtype Tagged (phantomtag :: anykind) a = Tagged { untag :: a }
+    deriving Functor

src/Keter/Config/V10.hs

@@ -21,7 +21,6 @@ import           Data.Maybe                        (catMaybes, fromMaybe, isJust
 import           Data.Proxy (Proxy(Proxy))
 import qualified Data.Set                          as Set
 import           Data.String                       (fromString)
-import           Data.Tagged
 import           Data.Vector                       (Vector)
 import qualified Data.Vector                       as V
 import           Data.Word                         (Word)

src/Keter/Proxy.hs

@@ -29,7 +29,6 @@ import           Network.Wai.Middleware.Gzip       (def)
 #endif
 import           Data.Monoid                       (mappend, mempty)
 import           Data.Proxy
-import           Data.Tagged
 import           Data.Text                         as T (pack, unwords)
 import           Data.Text.Encoding                (decodeUtf8With, encodeUtf8)
 import           Data.Text.Encoding.Error          (lenientDecode)