diff --git a/CHANGELOG.md b/CHANGELOG.md
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -8,6 +8,10 @@
 
 ## Unreleased
 
+## 0.6.3.1
+
+- Fix potential segfault in `shapePaths`
+
 ## 0.6.3.0
 
 - Fixed an issue in `Waterfall.Transforms` where negative coefficients to `scale` would produce a broken `Solid`
diff --git a/src/Waterfall/Internal/Edges.hs b/src/Waterfall/Internal/Edges.hs
--- a/src/Waterfall/Internal/Edges.hs
+++ b/src/Waterfall/Internal/Edges.hs
@@ -74,22 +74,6 @@
                 else pure [points]
     runToEnd
 
-allSubShapes :: ShapeEnum.ShapeEnum -> Ptr TopoDS.Shape -> Acquire [Ptr TopoDS.Shape]
-allSubShapes t s = do 
-    explorer <- Explorer.new s t
-    let go visited = do
-            isMore <- liftIO $ Explorer.more explorer
-            if isMore 
-                then do
-                    v <- liftIO $ Explorer.value explorer
-                    hash <- liftIO $ TopTools.ShapeMapHasher.hash v
-                    let add = if hash `elem` visited then id else (v:) 
-                    liftIO $ Explorer.next explorer
-                    add <$> go visited
-                else return []
-    go []
-
-    
 allSubShapesWithCopy :: ShapeEnum.ShapeEnum -> Ptr TopoDS.Shape -> Acquire [Ptr TopoDS.Shape]
 allSubShapesWithCopy t s = do 
     explorer <- Explorer.new s t
@@ -114,7 +98,7 @@
 allEdges s = traverse (liftIO . unsafeDowncast) =<< allSubShapesWithCopy ShapeEnum.Edge s 
 
 allWires :: Ptr TopoDS.Shape -> Acquire [Ptr TopoDS.Wire]
-allWires s = traverse (liftIO . unsafeDowncast) =<< allSubShapes ShapeEnum.Wire s 
+allWires s = traverse (liftIO . unsafeDowncast) =<< allSubShapesWithCopy ShapeEnum.Wire s
     
 wireEndpoints :: Ptr TopoDS.Wire -> IO (V3 Double, V3 Double)
 wireEndpoints wire = with (WireExplorer.fromWire wire) $ \explorer -> do
diff --git a/src/Waterfall/TwoD/Shape.hs b/src/Waterfall/TwoD/Shape.hs
--- a/src/Waterfall/TwoD/Shape.hs
+++ b/src/Waterfall/TwoD/Shape.hs
@@ -18,7 +18,7 @@
 import Waterfall.TwoD.Internal.Shape (Shape (..), union2D, difference2D, intersection2D, unions2D, intersections2D, emptyShape)
 import Waterfall.TwoD.Internal.Path2D (Path2D (..))
 import Waterfall.TwoD.Transforms (translate2D, rotate2D)
-import Waterfall.Internal.Finalizers (toAcquire, unsafeFromAcquire)
+import Waterfall.Internal.Finalizers (toAcquire, unsafeFromAcquire, unsafeFromAcquireT)
 import Waterfall.Internal.Edges (allWires)
 import qualified OpenCascade.BRepBuilderAPI.MakeFace as MakeFace
 import OpenCascade.Inheritance (upcast)
@@ -45,7 +45,7 @@
 -- Although this can only hold when the shape has one boundary path, 
 -- and is not guaranteed
 shapePaths :: Shape -> [Path2D] 
-shapePaths (Shape r) = fmap (Path2D . ComplexRawPath) . unsafeFromAcquire $ do
+shapePaths (Shape r) = fmap (Path2D . ComplexRawPath) . unsafeFromAcquireT $ do
     s <- toAcquire r 
     allWires s 
 
diff --git a/waterfall-cad.cabal b/waterfall-cad.cabal
--- a/waterfall-cad.cabal
+++ b/waterfall-cad.cabal
@@ -1,11 +1,11 @@
 cabal-version: 1.12
 
--- This file has been generated from package.yaml by hpack version 0.39.1.
+-- This file has been generated from package.yaml by hpack version 0.39.6.
 --
 -- see: https://github.com/sol/hpack
 
 name:           waterfall-cad
-version:        0.6.3.0
+version:        0.6.3.1
 synopsis:       Declarative CAD/Solid Modeling Library
 description:    Please see the README on GitHub at <https://github.com/joe-warren/opencascade-hs#readme>
 category:       Graphics
@@ -73,7 +73,7 @@
     , lattices >=2.0 && <3
     , lens ==5.*
     , linear >=1.21 && <2
-    , opencascade-hs >=0.6.3.0 && <0.7
+    , opencascade-hs >=0.6.3.1 && <0.7
     , primitive >=0.7 && <0.10
     , resourcet >=1.2 && <1.4
   default-language: Haskell2010