diff --git a/Lastik.cabal b/Lastik.cabal
--- a/Lastik.cabal
+++ b/Lastik.cabal
@@ -1,5 +1,5 @@
 Name:               Lastik
-Version:            0.6.3
+Version:            0.6.4
 License:            BSD3
 License-File:       LICENSE
 Author:             Tony Morris <code@tmorris.net>
diff --git a/System/Build/Args.hs b/System/Build/Args.hs
--- a/System/Build/Args.hs
+++ b/System/Build/Args.hs
@@ -1,3 +1,5 @@
+{-# LANGUAGE FlexibleInstances #-}
+
 -- | Functions for working with command line arguments and options.
 module System.Build.Args(
                           quote,
@@ -13,7 +15,8 @@
                           (^^^),
                           space,
                           searchPath,
-                          tryEnvs
+                          tryEnvs,
+                          ArgShow(..)
                         ) where
 
 import Control.Monad
@@ -23,10 +26,19 @@
 import System.Environment
 import System.FilePath
 
--- | Surrounds the given string in double-quotes.
+class ArgShow a where
+  arg :: a -> String
+
+instance ArgShow [Char] where
+  arg = id
+
+instance ArgShow Int where
+  arg = show
+
+-- | Surrounds the given string in double-quotes and escapes any already there.
 quote :: String
          -> String
-quote s = '"' : s ++ "\""
+quote s = '"' : (s >>= \x -> if x == '"' then "\\\"" else [x]) ++ "\""
 
 -- | An empty list if the boolean is @False@ otherwise the given string value with @'-'@ prepended.
 (~~) :: String
@@ -91,21 +103,21 @@
 --
 -- > "abc" ~~> Just "def" == "-abc \"def\""
 -- > "abc" ~~> Nothing == ""
-(~~>) :: (Show k) =>
+(~~>) :: (ArgShow k) =>
          String
          -> Maybe k
          -> String
-(~~>) k = param k ' ' show
+(~~>) k = param k ' ' arg
 
 -- | If the given value is @Nothing@ return the empty list, otherwise prepend @'-'@ followed by the first value then @':'@ followed by surrounding the result of @show@ in double-quotes.
 --
 -- > "abc" ~~> Just "def" == "-abc:\"def\""
 -- > "abc" ~~> Nothing == ""
-(-~>) :: (Show k) =>
+(-~>) :: (ArgShow k) =>
          String
          -> Maybe k
          -> String
-(-~>) k = param k ':' show
+(-~>) k = param k ':' arg
 
 -- | Removes all empty lists from the first argument the intercalates the second argument.
 --
@@ -134,8 +146,8 @@
            -> IO (Maybe a)
 tryEnvs es = do e <- getEnvironment
                 let k [] = Nothing
-                    k ((a, b):t) = fmap b (a `M.lookup` M.fromList e) `mplus` k t   
-                return (k es)    
+                    k ((a, b):t) = fmap b (a `M.lookup` M.fromList e) `mplus` k t
+                return (k es)
 
 
 -- not exported
diff --git a/System/Build/Java/Javac.hs b/System/Build/Java/Javac.hs
--- a/System/Build/Java/Javac.hs
+++ b/System/Build/Java/Javac.hs
@@ -68,6 +68,9 @@
   show None = "none"
   show All = "all"
 
+instance ArgShow Debug where
+  arg = show
+
 -- | Control whether annotation processing and/or compilation is done.
 newtype Proc = Proc Bool deriving Eq
 
@@ -88,6 +91,9 @@
   show (Proc False) = "none"
   show (Proc True) = "only"
 
+instance ArgShow Proc where
+  arg = show
+
 -- | Specify whether or not to generate class files for implicitly referenced files.
 newtype Implicit = Implicit Bool deriving Eq
 
@@ -107,6 +113,9 @@
 instance Show Implicit where
   show (Implicit False) = "none"
   show (Implicit True) = "class"
+
+instance ArgShow Implicit where
+  arg = show
 
 -- | Javac is the compiler for Java source files.
 data Javac = Javac {
diff --git a/System/Build/Java/Javadoc.hs b/System/Build/Java/Javadoc.hs
--- a/System/Build/Java/Javadoc.hs
+++ b/System/Build/Java/Javadoc.hs
@@ -90,6 +90,9 @@
   show S14 = "1.4"
   show S13 = "1.3"
 
+instance ArgShow SourceRelease where
+  arg = show
+
 -- | Javadoc is the compiler for Java API documentation.
 data Javadoc = Javadoc {
   overview :: Maybe FilePath,        -- ^ @-overview@
diff --git a/System/Build/Scala/Access.hs b/System/Build/Scala/Access.hs
--- a/System/Build/Scala/Access.hs
+++ b/System/Build/Scala/Access.hs
@@ -3,6 +3,8 @@
                                   Access(..)
                                 ) where
 
+import System.Build.Args
+
 -- | Show only public, protected/public (default) or all classes and members (public,protected,private)
 data Access = Public      -- ^ @public@
               | Protected -- ^ @protected@
@@ -13,3 +15,6 @@
   show Public = "public"
   show Protected = "protected"
   show Private = "private"
+
+instance ArgShow Access where
+  arg = show
diff --git a/System/Build/Scala/Debug.hs b/System/Build/Scala/Debug.hs
--- a/System/Build/Scala/Debug.hs
+++ b/System/Build/Scala/Debug.hs
@@ -3,6 +3,8 @@
                                  Debug(..)
                                ) where
 
+import System.Build.Args
+
 -- | Specify level of generated debugging info (none,source,line,vars,notailcalls)
 data Debug = None          -- ^ @none@
              | Source      -- ^ @source@
@@ -17,3 +19,6 @@
   show Line = "line"
   show Vars = "vars"
   show NoTailCalls = "notailcalls"
+
+instance ArgShow Debug where
+  arg = show
diff --git a/System/Build/Scala/Target.hs b/System/Build/Scala/Target.hs
--- a/System/Build/Scala/Target.hs
+++ b/System/Build/Scala/Target.hs
@@ -3,6 +3,8 @@
                                   Target(..)
                                 ) where
 
+import System.Build.Args
+
 -- | Specify for which target object files should be built (jvm-1.5,jvm-1.4,msil)
 data Target = JVM15   -- ^ @jvm-1.5@
               | JVM14 -- ^ @jvm-1.4@
@@ -13,3 +15,6 @@
   show JVM15 = "jvm-1.5"
   show JVM14 = "jvm-1.4"
   show MSIL = "msil"
+
+instance ArgShow Target where
+  arg = show