diff --git a/crates/fj-kernel/src/algorithms/sweep/vertex.rs b/crates/fj-kernel/src/algorithms/sweep/vertex.rs
index f348b561d..e99c493bc 100644
--- a/crates/fj-kernel/src/algorithms/sweep/vertex.rs
+++ b/crates/fj-kernel/src/algorithms/sweep/vertex.rs
@@ -184,7 +184,7 @@ mod tests {
             .build(&objects)?;
         let vertex = Vertex::partial()
             .with_position(Some([0.]))
-            .with_curve(Some(curve))
+            .with_curve(curve)
             .build(&objects)?;
 
         let half_edge =
diff --git a/crates/fj-kernel/src/algorithms/transform/edge.rs b/crates/fj-kernel/src/algorithms/transform/edge.rs
index 3a9bc69e8..5e96fbc03 100644
--- a/crates/fj-kernel/src/algorithms/transform/edge.rs
+++ b/crates/fj-kernel/src/algorithms/transform/edge.rs
@@ -25,7 +25,7 @@ impl TransformObject for PartialHalfEdge {
                 Ok(vertex
                     .into_partial()
                     .transform(transform, objects)?
-                    .with_curve(Some(curve.clone())))
+                    .with_curve(curve.clone()))
             },
         )?;
         let global_form = self
diff --git a/crates/fj-kernel/src/algorithms/transform/vertex.rs b/crates/fj-kernel/src/algorithms/transform/vertex.rs
index a86753e0d..b9db0f704 100644
--- a/crates/fj-kernel/src/algorithms/transform/vertex.rs
+++ b/crates/fj-kernel/src/algorithms/transform/vertex.rs
@@ -24,7 +24,7 @@ impl TransformObject for PartialVertex {
         // coordinates and thus transforming the curve takes care of it.
         Ok(Self::default()
             .with_position(self.position())
-            .with_curve(Some(curve))
+            .with_curve(curve)
             .with_surface_form(surface_form))
     }
 }
diff --git a/crates/fj-kernel/src/builder/cycle.rs b/crates/fj-kernel/src/builder/cycle.rs
index 0052f9f98..a2b5ca081 100644
--- a/crates/fj-kernel/src/builder/cycle.rs
+++ b/crates/fj-kernel/src/builder/cycle.rs
@@ -74,7 +74,7 @@ impl CycleBuilder for PartialCycle {
                 let [from, to] =
                     [(0., from), (1., to)].map(|(position, surface_form)| {
                         Vertex::partial()
-                            .with_curve(Some(curve.clone()))
+                            .with_curve(curve.clone())
                             .with_position(Some([position]))
                             .with_surface_form(surface_form)
                     });
diff --git a/crates/fj-kernel/src/builder/edge.rs b/crates/fj-kernel/src/builder/edge.rs
index f8e258842..f85b1bc45 100644
--- a/crates/fj-kernel/src/builder/edge.rs
+++ b/crates/fj-kernel/src/builder/edge.rs
@@ -75,7 +75,7 @@ impl HalfEdgeBuilder for PartialHalfEdge {
         let [back, front] = [a_curve, b_curve].map(|point_curve| {
             Vertex::partial()
                 .with_position(Some(point_curve))
-                .with_curve(Some(curve.clone()))
+                .with_curve(curve.clone())
                 .with_surface_form(surface_vertex.clone())
         });
 
@@ -127,7 +127,7 @@ impl HalfEdgeBuilder for PartialHalfEdge {
                 vertex.update_partial(|vertex| {
                     vertex
                         .with_position(Some([position]))
-                        .with_curve(Some(curve.clone()))
+                        .with_curve(curve.clone())
                 })
             });
 
diff --git a/crates/fj-kernel/src/partial/objects/edge.rs b/crates/fj-kernel/src/partial/objects/edge.rs
index 02c60af4b..7b5ffe3c9 100644
--- a/crates/fj-kernel/src/partial/objects/edge.rs
+++ b/crates/fj-kernel/src/partial/objects/edge.rs
@@ -131,7 +131,7 @@ impl PartialHalfEdge {
         let curve = self.curve.into_full(objects)?;
         let vertices = self.vertices.try_map_ext(|vertex| {
             vertex
-                .update_partial(|vertex| vertex.with_curve(Some(curve.clone())))
+                .update_partial(|vertex| vertex.with_curve(curve.clone()))
                 .into_full(objects)
         })?;
 
diff --git a/crates/fj-kernel/src/partial/objects/vertex.rs b/crates/fj-kernel/src/partial/objects/vertex.rs
index 8cad7c7ca..f3cd84539 100644
--- a/crates/fj-kernel/src/partial/objects/vertex.rs
+++ b/crates/fj-kernel/src/partial/objects/vertex.rs
@@ -46,13 +46,8 @@ impl PartialVertex {
     }
 
     /// Provide a curve for the partial vertex
-    pub fn with_curve(
-        mut self,
-        curve: Option<impl Into<MaybePartial<Curve>>>,
-    ) -> Self {
-        if let Some(curve) = curve {
-            self.curve = curve.into();
-        }
+    pub fn with_curve(mut self, curve: impl Into<MaybePartial<Curve>>) -> Self {
+        self.curve = curve.into();
         self
     }
 
diff --git a/crates/fj-kernel/src/validate/edge.rs b/crates/fj-kernel/src/validate/edge.rs
index ffc50c29f..2babcdf94 100644
--- a/crates/fj-kernel/src/validate/edge.rs
+++ b/crates/fj-kernel/src/validate/edge.rs
@@ -217,7 +217,7 @@ mod tests {
             vertices[1] = vertices[1]
                 .to_partial()
                 // Arranging for an equal but not identical curve here.
-                .with_curve(Some(valid.curve().to_partial()))
+                .with_curve(valid.curve().to_partial())
                 .build(&objects)?;
 
             HalfEdge::new(vertices, valid.global_form().clone())
diff --git a/crates/fj-kernel/src/validate/vertex.rs b/crates/fj-kernel/src/validate/vertex.rs
index 075c57cf1..3055f88fa 100644
--- a/crates/fj-kernel/src/validate/vertex.rs
+++ b/crates/fj-kernel/src/validate/vertex.rs
@@ -191,11 +191,11 @@ mod tests {
 
         let valid = Vertex::partial()
             .with_position(Some([0.]))
-            .with_curve(Some(
+            .with_curve(
                 Curve::partial()
                     .with_surface(Some(objects.surfaces.xy_plane()))
                     .update_as_u_axis(),
-            ))
+            )
             .build(&objects)?;
         let invalid = Vertex::new(
             valid.position(),
@@ -219,11 +219,11 @@ mod tests {
 
         let valid = Vertex::partial()
             .with_position(Some([0.]))
-            .with_curve(Some(
+            .with_curve(
                 Curve::partial()
                     .with_surface(Some(objects.surfaces.xy_plane()))
                     .update_as_u_axis(),
-            ))
+            )
             .build(&objects)?;
         let invalid = Vertex::new(
             valid.position(),