diff --git a/mealy.cabal b/mealy.cabal
--- a/mealy.cabal
+++ b/mealy.cabal
@@ -1,6 +1,6 @@
 cabal-version: 2.4
 name:          mealy
-version:       0.4.0
+version:       0.4.1
 license:       BSD-3-Clause
 copyright:     Tony Day (c) 2013 - 2022
 maintainer:    tonyday567@gmail.com
@@ -21,7 +21,7 @@
 
 category:      folding
 build-type:    Simple
-tested-with:   GHC ==8.8.4 || ==8.10.7 || ==9.2.4 || ==9.4.2
+tested-with:   GHC ==8.6.5 || ==8.8.4 || ==8.10.7 || ==9.2.5 || ==9.4.4
 
 source-repository head
   type:     git
@@ -37,20 +37,19 @@
   default-language: Haskell2010
   ghc-options:
     -Wall -Wcompat -Wincomplete-record-updates
-    -Wincomplete-uni-patterns -Wredundant-constraints -fwrite-ide-info
-    -hiedir=.hie
+    -Wincomplete-uni-patterns -Wredundant-constraints
 
   build-depends:
     , adjunctions        ^>=4.4
-    , base               >=4.13   && <5
+    , base               >=4.12   && <5
     , containers         ^>=0.6.2
     , mwc-probability    ^>=2.3.1
     , numhask            ^>=0.10
     , numhask-array      ^>=0.10.1
     , optics-core        ^>=0.4
-    , primitive          ^>=0.7.2
+    , primitive          >=0.7.2   && <0.9
     , profunctors        ^>=5.6.2
     , tdigest            ^>=0.2.1
-    , text               >=1.2.4 && < 2.1
-    , vector             ^>=0.12.3
-    , vector-algorithms  ^>=0.8.0
+    , text               >=1.2.4   && <2.1
+    , vector             >=0.12.3  && <0.14
+    , vector-algorithms  >=0.8.0   && <0.10
diff --git a/src/Data/Mealy.hs b/src/Data/Mealy.hs
--- a/src/Data/Mealy.hs
+++ b/src/Data/Mealy.hs
@@ -295,7 +295,7 @@
 --
 -- >>> fold (std 1) xs0
 -- 1.0126438036262801
-std :: (Divisive a, ExpField a) => a -> Mealy a a
+std :: (ExpField a) => a -> Mealy a a
 std r = (\s ss -> sqrt (ss - s ** (one + one))) <$> ma r <*> sqma r
 {-# INLINEABLE std #-}