diff --git a/Data/AList.hs b/Data/AList.hs
--- a/Data/AList.hs
+++ b/Data/AList.hs
@@ -11,9 +11,13 @@
 singleton x = AListTip x
 append = AListAppend 
 
+{-# INLINABLE fold #-}
 fold f base (AListAppend a b) = f (fold f base a) (fold f base b)
 fold f base (AListTip x) = x
 fold f base AListEmpty = base
+
+cons x alist = singleton x `append` alist 
+snoc alist x = alist `append` singleton x
 
 sum = fold (+) 0
 
diff --git a/alist.cabal b/alist.cabal
--- a/alist.cabal
+++ b/alist.cabal
@@ -10,7 +10,7 @@
 -- PVP summary:      +-+------- breaking API changes
 --                   | | +----- non-breaking API additions
 --                   | | | +--- code changes with no API change
-version:             0.1.0.5
+version:             0.1.0.6
 
 -- A short (one-line) description of the package.
 synopsis:            lists with O(1) append
@@ -60,7 +60,7 @@
   -- other-extensions:    
   
   -- Other library packages from which modules are imported.
-  build-depends:       base <10000
+  build-depends:       base >= 4.9 && < 5
   
   -- Directories containing source files.
   -- hs-source-dirs: