diff --git a/dataframe-core.cabal b/dataframe-core.cabal
--- a/dataframe-core.cabal
+++ b/dataframe-core.cabal
@@ -1,6 +1,6 @@
 cabal-version:      2.4
 name:               dataframe-core
-version:            1.1.0.0
+version:            1.1.0.1
 synopsis:           Core data structures for the dataframe library.
 description:
     Minimal interchange-format types for the @dataframe@ ecosystem:
diff --git a/src/DataFrame/Internal/RadixRank.hs b/src/DataFrame/Internal/RadixRank.hs
--- a/src/DataFrame/Internal/RadixRank.hs
+++ b/src/DataFrame/Internal/RadixRank.hs
@@ -1,4 +1,5 @@
 {-# LANGUAGE BangPatterns #-}
+{-# LANGUAGE ScopedTypeVariables #-}
 
 {- |
 Stable rank of a set of group representatives by the ascending unsigned order of
@@ -36,7 +37,7 @@
 
 -- | See the module header. @readHash@ supplies the hash of local group @gid@.
 rankByHash ::
-    (PrimMonad m) => (Int -> m Int) -> Int -> m (VU.Vector Int)
+    forall m. (PrimMonad m) => (Int -> m Int) -> Int -> m (VU.Vector Int)
 rankByHash readHash ng = do
     rankM <- VUM.new (max 1 ng)
     if ng <= 1
@@ -55,7 +56,14 @@
             keysB <- VUM.new ng
             orderB <- VUM.new ng
             counts <- VUM.new 256
-            let pass !shiftBits !srcK !srcO !dstK !dstO = do
+            let pass ::
+                    Int ->
+                    VUM.MVector (VUM.PrimState m) Int ->
+                    VUM.MVector (VUM.PrimState m) Int ->
+                    VUM.MVector (VUM.PrimState m) Int ->
+                    VUM.MVector (VUM.PrimState m) Int ->
+                    m ()
+                pass !shiftBits !srcK !srcO !dstK !dstO = do
                     VUM.set counts 0
                     let count !i
                             | i >= ng = pure ()