diff --git a/Data/Map/Static/Builder.hs b/Data/Map/Static/Builder.hs
index 486e19c..abb3ddb 100644
--- a/Data/Map/Static/Builder.hs
+++ b/Data/Map/Static/Builder.hs
@@ -9,8 +9,8 @@ import Data.Bits
 
 buildStaticMap :: (StaticElement i,StaticElement e,Ord i) => [(i,e)] -> String
 buildStaticMap lst = let  step :: Int -> [(i,e)] -> [(Int,(i,e))]
-                          step n chunk = let ss = findSplitSize (length chunk)
-                                             (h,d:t) = splitAt ss chunk
+                          step n chunk = let ss = findSplitSize (genericLength chunk)
+                                             (h,d:t) = genericSplitAt ss chunk
                                          in if null chunk
                                             then []
                                             else (n,d):((step (n*2) h)++(step (n*2+1) t))
@@ -24,19 +24,19 @@ buildStaticMap lst = let  step :: Int -> [(i,e)] -> [(Int,(i,e))]
                           len = length heap
                       in "StaticMap ("++buildStaticArray (1,len) (map fst heap)++") ("++buildStaticArray (1,len) (map snd heap)++")"
 
-maxSize :: Int -> Int
-maxSize d = (1 `shiftL` d) - 1
+maxSize :: Integer -> Integer
+maxSize d = (floor $ 2^^d) - 1
 
-treeDepth :: Int -> Int
+treeDepth :: Integer -> Integer
 treeDepth sz = find' [0..]
     where
-      find' (x:xs) = if 1 `shiftL` x > sz
+      find' (x:xs) = if (floor $ 2^^x) > sz
                      then x
                      else find' xs
 
-findSplitSize :: Int -> Int
+findSplitSize :: Integer -> Integer
 findSplitSize len = let depth = treeDepth len
                         free = (maxSize depth) - len
-                    in if free <= (1 `shiftL` (depth - 2))
+                    in if free <= (floor $ 2 ^^ (depth - 2))
                        then maxSize (depth - 1)
                        else len - (maxSize (depth - 2)) - 1
diff --git a/encoding.cabal b/encoding.cabal
index 0d14f65..1394a3e 100644
--- a/encoding.cabal
+++ b/encoding.cabal
@@ -1,16 +1,16 @@
-Name:		encoding
-Version:	0.8.2
-Author:		Henning Günther
-Maintainer:	daniel@wagner-home.com
-License:	BSD3
+Name:           encoding
+Version:        0.8.2
+Author:         Henning Günther
+Maintainer:     daniel@wagner-home.com
+License:        BSD3
 License-File:   LICENSE
-Synopsis:	A library for various character encodings
+Synopsis:       A library for various character encodings
 Description:
-	Haskell has excellect handling of unicode, the Char type covers all unicode chars. Unfortunately, there's no possibility to read or write something to the outer world in an encoding other than ascii due to the lack of support for encodings. This library should help with that.
-Category:	Codec
-Homepage:	http://code.haskell.org/encoding/
-Cabal-Version:	>=1.8
-Build-Type:	Custom
+        Haskell has excellect handling of unicode, the Char type covers all unicode chars. Unfortunately, there's no possibility to read or write something to the outer world in an encoding other than ascii due to the lack of support for encodings. This library should help with that.
+Category:       Codec
+Homepage:       http://code.haskell.org/encoding/
+Cabal-Version:  >=1.8
+Build-Type:     Custom
 Extra-Source-Files:
   CHANGELOG
   Data/Encoding/Preprocessor/Mapping.hs
@@ -36,11 +36,12 @@ Source-Repository this
 
 Custom-Setup
   Setup-Depends: base >=3 && <5,
-                 Cabal >=1.24 && <2.5,
+                 Cabal >=1.24 && <4,
                  containers,
                  filepath,
                  ghc-prim,
-                 HaXml >=1.22 && <1.26
+                 HaXml >=1.22 && <1.26,
+                 deepseq
 
 Library
   Build-Depends: array >=0.4 && <0.6,
diff --git a/stack.yaml b/stack.yaml
index 156eced..ebf8545 100644
--- a/stack.yaml
+++ b/stack.yaml
@@ -15,7 +15,7 @@
 # resolver:
 #  name: custom-snapshot
 #  location: "./custom-snapshot.yaml"
-resolver: lts-14.6
+resolver: lts-15.0
 
 # User packages to be built.
 # Various formats can be used as shown in the example below.
diff --git a/stack.yaml.lock b/stack.yaml.lock
index 81a2fc4..4af2634 100644
--- a/stack.yaml.lock
+++ b/stack.yaml.lock
@@ -13,7 +13,7 @@ packages:
     hackage: HaXml-1.25.5
 snapshots:
 - completed:
-    size: 524127
-    url: https://raw.githubusercontent.com/commercialhaskell/stackage-snapshots/master/lts/14/6.yaml
-    sha256: dc70dfb45e2c32f54719819bd055f46855dd4b3bd2e58b9f3f38729a2d553fbb
-  original: lts-14.6
+    size: 488576
+    url: https://raw.githubusercontent.com/commercialhaskell/stackage-snapshots/master/lts/15/0.yaml
+    sha256: e4b6a87b47ec1cf63a7f1a0884a3b276fce2b0d174a10e8753c4f618e7983568
+  original: lts-15.0