diff --git a/CHANGELOG.md b/CHANGELOG.md
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,12 @@
 # Revision history for imp-ppl
 
+## 0.1.0.1 — 2026-08-07
+
+* Lower the `base` bound to 4.18, supporting GHC 9.6 onwards.
+* Relax the benchmark `time` bound to allow 1.15.
+
+No functional changes.
+
 ## 0.1.0.0 — 2026-08-06
 
 * First release: the graded monad DSL, BDD compilation, and four credal
diff --git a/imp-ppl.cabal b/imp-ppl.cabal
--- a/imp-ppl.cabal
+++ b/imp-ppl.cabal
@@ -1,6 +1,6 @@
 cabal-version: 3.0
 name:          imp-ppl
-version:       0.1.0.0
+version:       0.1.0.1
 synopsis:      Imprecise probabilistic programming via BDDs
 description:
   A DSL for discrete probabilistic programs with Knightian uncertainty,
@@ -17,7 +17,10 @@
 homepage:      https://github.com/jacklc3/imp
 bug-reports:   https://github.com/jacklc3/imp/issues
 build-type:    Simple
-tested-with:   GHC == 9.10.1
+tested-with:   GHC == 9.6.7
+             , GHC == 9.8.4
+             , GHC == 9.10.1
+             , GHC == 9.12.1
              , GHC == 9.14.1
 
 extra-doc-files:
@@ -31,7 +34,7 @@
 source-repository this
   type:     git
   location: https://github.com/jacklc3/imp.git
-  tag:      v0.1.0.0
+  tag:      v0.1.0.1
 
 -- Development-only visualisation and benchmark executables.
 flag dev
@@ -66,7 +69,7 @@
     Imp.Examples.Polytope
     Imp.Examples.TwoChild
   build-depends:
-    base >= 4.20 && < 5,
+    base >= 4.18 && < 5,
     containers >= 0.6 && < 0.9,
     mtl >= 2.3 && < 2.4,
     vector >= 0.13 && < 0.14
@@ -102,7 +105,7 @@
   build-depends:
     base,
     imp-ppl,
-    time >= 1.12 && < 1.15
+    time >= 1.12 && < 1.16
   default-language: GHC2021
   default-extensions:
     DataKinds
diff --git a/src/Imp/Inference/Enumerate.hs b/src/Imp/Inference/Enumerate.hs
--- a/src/Imp/Inference/Enumerate.hs
+++ b/src/Imp/Inference/Enumerate.hs
@@ -14,6 +14,7 @@
 import Control.Monad.State.Strict (runState)
 import Data.Bool (bool)
 import Data.Functor.Compose (Compose(..))
+import qualified Data.List as L
 import Data.Maybe (mapMaybe)
 import qualified Data.IntMap.Strict as IntMap
 import Data.Map.Strict (Map)
@@ -35,7 +36,7 @@
 -- | Compute the min and max of a non-empty list in a single strict pass.
 bounds :: Ord a => [a] -> (a, a)
 bounds []     = error "No feasible probabilities"
-bounds (x:xs) = foldl' step (x, x) xs
+bounds (x:xs) = L.foldl' step (x, x) xs
   where step (!mn, !mx) y = (min mn y, max mx y)
 
 -- | Precise marginal distribution. Only for programs with no Knightian choices.
diff --git a/src/Imp/Inference/Symbolic.hs b/src/Imp/Inference/Symbolic.hs
--- a/src/Imp/Inference/Symbolic.hs
+++ b/src/Imp/Inference/Symbolic.hs
@@ -11,6 +11,7 @@
 
 import Data.Bits (bit, testBit, clearBit, (.|.))
 import Data.Bool (bool)
+import qualified Data.List as L
 import Data.Map.Strict (Map)
 import qualified Data.Map.Strict as Map
 
@@ -59,7 +60,7 @@
 -- | Bounds over the feasible corners of the parameter box.
 optimizeRatio :: PolyS -> PolyS -> (Double, Double)
 optimizeRatio den num =
-  let mask = foldl' (.|.) 0 (Map.keys (unPoly num) ++ Map.keys (unPoly den))
+  let mask = L.foldl' (.|.) 0 (Map.keys (unPoly num) ++ Map.keys (unPoly den))
       free = [ i | i <- takeWhile (\i -> bit (2 * i) <= mask) [0 ..]
                  , testBit mask (2 * i) || testBit mask (2 * i + 1) ]
   in case cornerRatios free den num of
diff --git a/src/Imp/Semiring.hs b/src/Imp/Semiring.hs
--- a/src/Imp/Semiring.hs
+++ b/src/Imp/Semiring.hs
@@ -9,6 +9,7 @@
   ) where
 
 import Data.Bits ((.|.))
+import qualified Data.List as L
 import qualified Data.Map.Strict as Map
 import qualified Data.Vector as V
 
@@ -24,7 +25,7 @@
 
 -- | Sum a list in the semiring.
 sumS :: Semiring s => [s] -> s
-sumS = foldl' (.+.) zero
+sumS = L.foldl' (.+.) zero
 
 -- | Probability semiring for precise WMC.
 newtype ProbS = ProbS { unProb :: Double }
diff --git a/viz/Viz.hs b/viz/Viz.hs
--- a/viz/Viz.hs
+++ b/viz/Viz.hs
@@ -11,6 +11,7 @@
   ) where
 
 import Data.List (sort)
+import qualified Data.List as L
 import qualified Data.IntMap.Strict as IntMap
 import qualified Data.Map.Strict as Map
 import qualified Data.Set as Set
@@ -355,7 +356,7 @@
 
 -- | All internal node ids reachable from the given roots, each visited once.
 collectNids :: BDDManager -> [BDD] -> [NodeId]
-collectNids mgr = Set.toList . foldl' go Set.empty
+collectNids mgr = Set.toList . L.foldl' go Set.empty
   where
     go seen BDDTrue       = seen
     go seen BDDFalse      = seen
diff --git a/viz/Viz/ConvexHull.hs b/viz/Viz/ConvexHull.hs
--- a/viz/Viz/ConvexHull.hs
+++ b/viz/Viz/ConvexHull.hs
@@ -4,6 +4,7 @@
   ) where
 
 import Data.List (sort, nubBy)
+import qualified Data.List as L
 
 -- | Compute the convex hull of a set of 2D points.
 --   Returns the hull vertices in counterclockwise order.
@@ -18,7 +19,7 @@
       in  init lower ++ init upper
   where
     unique = dedup2D pts
-    buildHull = foldl' add []
+    buildHull = L.foldl' add []
     add stack p = p : dropRightTurns stack
       where
         dropRightTurns (b : a : rest)