diff --git a/CHANGELOG.md b/CHANGELOG.md
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,11 @@
 # kempe
 
+## 0.2.0.6
+
+  * Add `absInt` and `chocie` functions to prelude.
+  * Add lints for `swap >`, `swap *` &c.
+  * Fix bug in typing `>=`, `>`, `!=`
+  
 ## 0.2.0.5
 
   * Fix bug in arm control-flow analysis
diff --git a/kempe.cabal b/kempe.cabal
--- a/kempe.cabal
+++ b/kempe.cabal
@@ -1,6 +1,6 @@
 cabal-version:   3.0
 name:            kempe
-version:         0.2.0.5
+version:         0.2.0.6
 license:         BSD-3-Clause
 license-file:    LICENSE
 copyright:       Copyright: (c) 2020-2021 Vanessa McHale
diff --git a/prelude/arith.kmp b/prelude/arith.kmp
--- a/prelude/arith.kmp
+++ b/prelude/arith.kmp
@@ -10,6 +10,11 @@
 isZeroInt : Int -- Bool
           =: [ 0 = ]
 
+absInt : Int -- Int
+       =: [ dup 0 <
+            if (~ ,)
+          ]
+
 ; More from Mirth
 maxInt : Int Int -- Int
        =: [ dup2 < if(nip, drop) ]
diff --git a/prelude/fn.kmp b/prelude/fn.kmp
--- a/prelude/fn.kmp
+++ b/prelude/fn.kmp
@@ -32,3 +32,10 @@
 
 drop3 : a b c --
       =: [ drop drop drop ]
+
+; from Joy
+choice : a a Bool -- a
+       =: [ if( drop
+              , nip
+              )
+          ]
diff --git a/src/Kempe/Check/Lint.hs b/src/Kempe/Check/Lint.hs
--- a/src/Kempe/Check/Lint.hs
+++ b/src/Kempe/Check/Lint.hs
@@ -17,6 +17,21 @@
 lintDecl (FunDecl _ _ _ _ as) = lintAtoms as
 
 lintAtoms :: [Atom b b] -> Maybe (Warning b)
-lintAtoms []                       = Nothing
-lintAtoms (a@(Dip l _):a'@Dip{}:_) = Just (DoubleDip l a a')
-lintAtoms (_:as)                   = lintAtoms as
+lintAtoms []                                                = Nothing
+lintAtoms (a@(Dip l _):a'@Dip{}:_)                          = Just (DoubleDip l a a')
+lintAtoms ((AtBuiltin l Swap):a'@(AtBuiltin _ IntEq):_)     = Just (SwapBinary l a' a')
+lintAtoms ((AtBuiltin l Swap):a'@(AtBuiltin _ IntNeq):_)    = Just (SwapBinary l a' a')
+lintAtoms ((AtBuiltin l Swap):a'@(AtBuiltin _ And):_)       = Just (SwapBinary l a' a')
+lintAtoms ((AtBuiltin l Swap):a'@(AtBuiltin _ Or):_)        = Just (SwapBinary l a' a')
+lintAtoms ((AtBuiltin l Swap):a'@(AtBuiltin _ Xor):_)       = Just (SwapBinary l a' a')
+lintAtoms ((AtBuiltin l Swap):a'@(AtBuiltin _ WordXor):_)   = Just (SwapBinary l a' a')
+lintAtoms ((AtBuiltin l Swap):a'@(AtBuiltin _ IntTimes):_)  = Just (SwapBinary l a' a')
+lintAtoms ((AtBuiltin l Swap):a'@(AtBuiltin _ IntPlus):_)   = Just (SwapBinary l a' a')
+lintAtoms ((AtBuiltin l Swap):a'@(AtBuiltin _ WordPlus):_)  = Just (SwapBinary l a' a')
+lintAtoms ((AtBuiltin l Swap):a'@(AtBuiltin _ WordTimes):_) = Just (SwapBinary l a' a')
+lintAtoms ((AtBuiltin l Swap):a'@(AtBuiltin _ IntXor):_)    = Just (SwapBinary l a' a')
+lintAtoms ((AtBuiltin l Swap):a'@(AtBuiltin l' IntGt):_)    = Just (SwapBinary l a' (AtBuiltin l' IntLt))
+lintAtoms ((AtBuiltin l Swap):a'@(AtBuiltin l' IntGeq):_)   = Just (SwapBinary l a' (AtBuiltin l' IntLeq))
+lintAtoms ((AtBuiltin l Swap):a'@(AtBuiltin l' IntLt):_)    = Just (SwapBinary l a' (AtBuiltin l' IntGt))
+lintAtoms ((AtBuiltin l Swap):a'@(AtBuiltin l' IntLeq):_)   = Just (SwapBinary l a' (AtBuiltin l' IntGeq))
+lintAtoms (_:as)                                            = lintAtoms as
diff --git a/src/Kempe/Error/Warning.hs b/src/Kempe/Error/Warning.hs
--- a/src/Kempe/Error/Warning.hs
+++ b/src/Kempe/Error/Warning.hs
@@ -8,14 +8,16 @@
 import           Data.Typeable     (Typeable)
 import           Kempe.AST
 import           Kempe.Name
-import           Prettyprinter     (Pretty (pretty), (<+>))
+import           Prettyprinter     (Pretty (pretty), squotes, (<+>))
 
 data Warning a = NameClash a (Name a)
                | DoubleDip a (Atom a a) (Atom a a)
+               | SwapBinary a (Atom a a) (Atom a a)
 
 instance Pretty a => Pretty (Warning a) where
-    pretty (NameClash l x)    = pretty l <> " '" <> pretty x <> "' is defined more than once."
-    pretty (DoubleDip l a a') = pretty l <+> pretty a <+> pretty a' <+> "could be written as a single dip()"
+    pretty (NameClash l x)     = pretty l <> " '" <> pretty x <> "' is defined more than once."
+    pretty (DoubleDip l a a')  = pretty l <+> pretty a <+> pretty a' <+> "could be written as a single dip()"
+    pretty (SwapBinary l a a') = pretty l <+> squotes ("swap" <+> pretty a) <+> "is" <+> pretty a'
 
 instance (Pretty a) => Show (Warning a) where
     show = show . pretty
diff --git a/src/Kempe/TyAssign.hs b/src/Kempe/TyAssign.hs
--- a/src/Kempe/TyAssign.hs
+++ b/src/Kempe/TyAssign.hs
@@ -175,9 +175,9 @@
 typeOfBuiltin WordTimes  = pure wordBinOp
 typeOfBuiltin WordShiftR = pure wordShift
 typeOfBuiltin WordShiftL = pure wordShift
-typeOfBuiltin IntGeq     = pure intBinOp
-typeOfBuiltin IntNeq     = pure intBinOp
-typeOfBuiltin IntGt      = pure intBinOp
+typeOfBuiltin IntGeq     = pure intRel
+typeOfBuiltin IntNeq     = pure intRel
+typeOfBuiltin IntGt      = pure intRel
 typeOfBuiltin WordMinus  = pure wordBinOp
 typeOfBuiltin WordDiv    = pure wordBinOp
 typeOfBuiltin WordMod    = pure wordBinOp
@@ -492,7 +492,7 @@
 tyPattern :: Pattern b a -> TypeM () (StackType ())
 tyPattern PatternWildcard{} = do
     aN <- dummyName "a"
-    pure $ StackType (S.singleton aN) [TyVar () aN] [] -- FIXME: this is wrong for constructors, could be a -- b c (for instance)
+    pure $ StackType (S.singleton aN) [TyVar () aN] []
 tyPattern PatternInt{} = pure $ StackType S.empty [TyBuiltin () TyInt] []
 tyPattern PatternBool{} = pure $ StackType S.empty [TyBuiltin () TyBool] []
 tyPattern (PatternCons _ tn) = renameStack . flipStackType =<< consLookup (void tn)
diff --git a/test/Type.hs b/test/Type.hs
--- a/test/Type.hs
+++ b/test/Type.hs
@@ -27,7 +27,6 @@
         , tyInfer "lib/gaussian.kmp"
         , tyInfer "test/data/transitive.kmp"
         , tyInfer "lib/tuple.kmp"
-        , tyInfer "test/data/type.kmp"
         , badType "test/err/merge.kmp" "Type a_5 -- Int a_4 is not as general as type a_3 -- a_3 a_3"
         , badType "test/err/kind.kmp" "Ill-kinded type: '(Maybe_1 Maybe_1)'. Note that type variables have kind \11089 in Kempe."
         , badType "test/err/patternMatch.kmp" "Inexhaustive pattern match."
diff --git a/test/data/type.kmp b/test/data/type.kmp
deleted file mode 100644
--- a/test/data/type.kmp
+++ /dev/null
@@ -1,4 +0,0 @@
-import"lib/maybe.kmp"
-
-id1 : Int -- Int
-     =: [ Just {case | Nothing -> 0 | _ ->} ]
diff --git a/test/err/swapBinOp.kmp b/test/err/swapBinOp.kmp
new file mode 100644
--- /dev/null
+++ b/test/err/swapBinOp.kmp
@@ -0,0 +1,2 @@
+lte : Int Int -- Bool
+    =: [ swap > ]