From 43cc14cff2fd70f1eda39af122bd43515323f9df Mon Sep 17 00:00:00 2001
From: Hanno Braun <hanno@braun-odw.eu>
Date: Thu, 22 Sep 2022 12:39:24 +0200
Subject: [PATCH 01/26] Make curve in `VertexBuilder` optional

---
 .../fj-kernel/src/algorithms/sweep/vertex.rs  |  2 +-
 crates/fj-kernel/src/builder/vertex.rs        | 19 ++++++++++++-------
 crates/fj-kernel/src/objects/vertex.rs        |  7 ++-----
 3 files changed, 15 insertions(+), 13 deletions(-)

diff --git a/crates/fj-kernel/src/algorithms/sweep/vertex.rs b/crates/fj-kernel/src/algorithms/sweep/vertex.rs
index 2aad1162d..e4fa1b597 100644
--- a/crates/fj-kernel/src/algorithms/sweep/vertex.rs
+++ b/crates/fj-kernel/src/algorithms/sweep/vertex.rs
@@ -161,7 +161,7 @@ mod tests {
 
         let surface = Surface::xz_plane();
         let curve = Curve::builder(&stores, surface).build_u_axis();
-        let vertex = Vertex::builder([0.], curve).build();
+        let vertex = Vertex::builder([0.]).with_curve(curve).build();
 
         let half_edge = (vertex, surface).sweep([0., 0., 1.], &stores);
 
diff --git a/crates/fj-kernel/src/builder/vertex.rs b/crates/fj-kernel/src/builder/vertex.rs
index 50587c19c..ba51ae774 100644
--- a/crates/fj-kernel/src/builder/vertex.rs
+++ b/crates/fj-kernel/src/builder/vertex.rs
@@ -10,7 +10,7 @@ pub struct VertexBuilder {
     pub position: Point<1>,
 
     /// The curve that the [`Vertex`] is defined in
-    pub curve: Curve,
+    pub curve: Option<Curve>,
 
     /// The surface form of the [`Vertex`]
     ///
@@ -26,6 +26,12 @@ pub struct VertexBuilder {
 }
 
 impl VertexBuilder {
+    /// Build the [`Vertex`] with the provided curve
+    pub fn with_curve(mut self, curve: Curve) -> Self {
+        self.curve = Some(curve);
+        self
+    }
+
     /// Build the [`Vertex`] with the provided surface form
     pub fn with_surface_form(mut self, surface_form: SurfaceVertex) -> Self {
         self.surface_form = Some(surface_form);
@@ -40,13 +46,12 @@ impl VertexBuilder {
 
     /// Finish building the [`Vertex`]
     pub fn build(self) -> Vertex {
+        let curve = self.curve.expect("Can't build `Vertex` without `Curve`");
+
         let surface_form = self.surface_form.unwrap_or_else(|| {
             SurfaceVertexBuilder {
-                position: self
-                    .curve
-                    .path()
-                    .point_from_path_coords(self.position),
-                surface: *self.curve.surface(),
+                position: curve.path().point_from_path_coords(self.position),
+                surface: *curve.surface(),
                 global_form: self.global_form,
             }
             .build()
@@ -54,7 +59,7 @@ impl VertexBuilder {
 
         let global_form = *surface_form.global_form();
 
-        Vertex::new(self.position, self.curve, surface_form, global_form)
+        Vertex::new(self.position, curve, surface_form, global_form)
     }
 }
 
diff --git a/crates/fj-kernel/src/objects/vertex.rs b/crates/fj-kernel/src/objects/vertex.rs
index 65622cfee..feb26a437 100644
--- a/crates/fj-kernel/src/objects/vertex.rs
+++ b/crates/fj-kernel/src/objects/vertex.rs
@@ -22,13 +22,10 @@ pub struct Vertex {
 
 impl Vertex {
     /// Build a `Vertex` using [`VertexBuilder`]
-    pub fn builder(
-        position: impl Into<Point<1>>,
-        curve: Curve,
-    ) -> VertexBuilder {
+    pub fn builder(position: impl Into<Point<1>>) -> VertexBuilder {
         VertexBuilder {
             position: position.into(),
-            curve,
+            curve: None,
             surface_form: None,
             global_form: None,
         }

From f56bef4b2af79d804c7cd5a749f043a916d5cca9 Mon Sep 17 00:00:00 2001
From: Hanno Braun <hanno@braun-odw.eu>
Date: Thu, 22 Sep 2022 12:42:01 +0200
Subject: [PATCH 02/26] Make position in `VertexBuilder` optional

---
 crates/fj-kernel/src/algorithms/sweep/vertex.rs |  5 ++++-
 crates/fj-kernel/src/builder/vertex.rs          | 15 ++++++++++++---
 crates/fj-kernel/src/objects/vertex.rs          |  4 ++--
 3 files changed, 18 insertions(+), 6 deletions(-)

diff --git a/crates/fj-kernel/src/algorithms/sweep/vertex.rs b/crates/fj-kernel/src/algorithms/sweep/vertex.rs
index e4fa1b597..51f53f29b 100644
--- a/crates/fj-kernel/src/algorithms/sweep/vertex.rs
+++ b/crates/fj-kernel/src/algorithms/sweep/vertex.rs
@@ -161,7 +161,10 @@ mod tests {
 
         let surface = Surface::xz_plane();
         let curve = Curve::builder(&stores, surface).build_u_axis();
-        let vertex = Vertex::builder([0.]).with_curve(curve).build();
+        let vertex = Vertex::builder()
+            .with_position([0.])
+            .with_curve(curve)
+            .build();
 
         let half_edge = (vertex, surface).sweep([0., 0., 1.], &stores);
 
diff --git a/crates/fj-kernel/src/builder/vertex.rs b/crates/fj-kernel/src/builder/vertex.rs
index ba51ae774..60d43fda4 100644
--- a/crates/fj-kernel/src/builder/vertex.rs
+++ b/crates/fj-kernel/src/builder/vertex.rs
@@ -7,7 +7,7 @@ use crate::objects::{Curve, GlobalVertex, Surface, SurfaceVertex, Vertex};
 /// Also see [`Vertex::builder`].
 pub struct VertexBuilder {
     /// The position of the [`Vertex`] on the [`Curve`]
-    pub position: Point<1>,
+    pub position: Option<Point<1>>,
 
     /// The curve that the [`Vertex`] is defined in
     pub curve: Option<Curve>,
@@ -26,6 +26,12 @@ pub struct VertexBuilder {
 }
 
 impl VertexBuilder {
+    /// Build the [`Vertex`] with the provided position
+    pub fn with_position(mut self, position: impl Into<Point<1>>) -> Self {
+        self.position = Some(position.into());
+        self
+    }
+
     /// Build the [`Vertex`] with the provided curve
     pub fn with_curve(mut self, curve: Curve) -> Self {
         self.curve = Some(curve);
@@ -46,11 +52,14 @@ impl VertexBuilder {
 
     /// Finish building the [`Vertex`]
     pub fn build(self) -> Vertex {
+        let position = self
+            .position
+            .expect("Cant' build `Vertex` without position");
         let curve = self.curve.expect("Can't build `Vertex` without `Curve`");
 
         let surface_form = self.surface_form.unwrap_or_else(|| {
             SurfaceVertexBuilder {
-                position: curve.path().point_from_path_coords(self.position),
+                position: curve.path().point_from_path_coords(position),
                 surface: *curve.surface(),
                 global_form: self.global_form,
             }
@@ -59,7 +68,7 @@ impl VertexBuilder {
 
         let global_form = *surface_form.global_form();
 
-        Vertex::new(self.position, curve, surface_form, global_form)
+        Vertex::new(position, curve, surface_form, global_form)
     }
 }
 
diff --git a/crates/fj-kernel/src/objects/vertex.rs b/crates/fj-kernel/src/objects/vertex.rs
index feb26a437..9feed0c46 100644
--- a/crates/fj-kernel/src/objects/vertex.rs
+++ b/crates/fj-kernel/src/objects/vertex.rs
@@ -22,9 +22,9 @@ pub struct Vertex {
 
 impl Vertex {
     /// Build a `Vertex` using [`VertexBuilder`]
-    pub fn builder(position: impl Into<Point<1>>) -> VertexBuilder {
+    pub fn builder() -> VertexBuilder {
         VertexBuilder {
-            position: position.into(),
+            position: None,
             curve: None,
             surface_form: None,
             global_form: None,

From b192af9ab5a213a92dae1606108643ea63d76cfc Mon Sep 17 00:00:00 2001
From: Hanno Braun <hanno@braun-odw.eu>
Date: Thu, 22 Sep 2022 12:44:00 +0200
Subject: [PATCH 03/26] Derive `Default` for `VertexBuilder`

---
 crates/fj-kernel/src/builder/vertex.rs | 1 +
 crates/fj-kernel/src/objects/vertex.rs | 7 +------
 2 files changed, 2 insertions(+), 6 deletions(-)

diff --git a/crates/fj-kernel/src/builder/vertex.rs b/crates/fj-kernel/src/builder/vertex.rs
index 60d43fda4..8659fb3b8 100644
--- a/crates/fj-kernel/src/builder/vertex.rs
+++ b/crates/fj-kernel/src/builder/vertex.rs
@@ -5,6 +5,7 @@ use crate::objects::{Curve, GlobalVertex, Surface, SurfaceVertex, Vertex};
 /// API for building a [`Vertex`]
 ///
 /// Also see [`Vertex::builder`].
+#[derive(Default)]
 pub struct VertexBuilder {
     /// The position of the [`Vertex`] on the [`Curve`]
     pub position: Option<Point<1>>,
diff --git a/crates/fj-kernel/src/objects/vertex.rs b/crates/fj-kernel/src/objects/vertex.rs
index 9feed0c46..022fe2c49 100644
--- a/crates/fj-kernel/src/objects/vertex.rs
+++ b/crates/fj-kernel/src/objects/vertex.rs
@@ -23,12 +23,7 @@ pub struct Vertex {
 impl Vertex {
     /// Build a `Vertex` using [`VertexBuilder`]
     pub fn builder() -> VertexBuilder {
-        VertexBuilder {
-            position: None,
-            curve: None,
-            surface_form: None,
-            global_form: None,
-        }
+        VertexBuilder::default()
     }
 
     /// Construct an instance of `Vertex`

From 56f44d78e1e2dced11cfebd296bab6826adc2c6c Mon Sep 17 00:00:00 2001
From: Hanno Braun <hanno@braun-odw.eu>
Date: Thu, 22 Sep 2022 12:45:28 +0200
Subject: [PATCH 04/26] Rename `VertexBuilder` to `PartialVertex`

The new name describes what it is, while the old name ascribes a use
case. Since I intend to use `PartialVertex` (and its other "builder"
siblings) for other use cases too, the new name is more appropriate, I
think.
---
 crates/fj-kernel/src/builder/mod.rs    | 2 +-
 crates/fj-kernel/src/builder/vertex.rs | 4 ++--
 crates/fj-kernel/src/objects/vertex.rs | 8 ++++----
 3 files changed, 7 insertions(+), 7 deletions(-)

diff --git a/crates/fj-kernel/src/builder/mod.rs b/crates/fj-kernel/src/builder/mod.rs
index 4f8aaccef..e003cb264 100644
--- a/crates/fj-kernel/src/builder/mod.rs
+++ b/crates/fj-kernel/src/builder/mod.rs
@@ -17,5 +17,5 @@ pub use self::{
     shell::ShellBuilder,
     sketch::SketchBuilder,
     solid::SolidBuilder,
-    vertex::{GlobalVertexBuilder, SurfaceVertexBuilder, VertexBuilder},
+    vertex::{GlobalVertexBuilder, PartialVertex, SurfaceVertexBuilder},
 };
diff --git a/crates/fj-kernel/src/builder/vertex.rs b/crates/fj-kernel/src/builder/vertex.rs
index 8659fb3b8..191f58e93 100644
--- a/crates/fj-kernel/src/builder/vertex.rs
+++ b/crates/fj-kernel/src/builder/vertex.rs
@@ -6,7 +6,7 @@ use crate::objects::{Curve, GlobalVertex, Surface, SurfaceVertex, Vertex};
 ///
 /// Also see [`Vertex::builder`].
 #[derive(Default)]
-pub struct VertexBuilder {
+pub struct PartialVertex {
     /// The position of the [`Vertex`] on the [`Curve`]
     pub position: Option<Point<1>>,
 
@@ -26,7 +26,7 @@ pub struct VertexBuilder {
     pub global_form: Option<GlobalVertex>,
 }
 
-impl VertexBuilder {
+impl PartialVertex {
     /// Build the [`Vertex`] with the provided position
     pub fn with_position(mut self, position: impl Into<Point<1>>) -> Self {
         self.position = Some(position.into());
diff --git a/crates/fj-kernel/src/objects/vertex.rs b/crates/fj-kernel/src/objects/vertex.rs
index 022fe2c49..f93d57688 100644
--- a/crates/fj-kernel/src/objects/vertex.rs
+++ b/crates/fj-kernel/src/objects/vertex.rs
@@ -2,7 +2,7 @@ use fj_math::Point;
 use pretty_assertions::assert_eq;
 
 use crate::builder::{
-    GlobalVertexBuilder, SurfaceVertexBuilder, VertexBuilder,
+    GlobalVertexBuilder, PartialVertex, SurfaceVertexBuilder,
 };
 
 use super::{Curve, Surface};
@@ -21,9 +21,9 @@ pub struct Vertex {
 }
 
 impl Vertex {
-    /// Build a `Vertex` using [`VertexBuilder`]
-    pub fn builder() -> VertexBuilder {
-        VertexBuilder::default()
+    /// Build a `Vertex` using [`PartialVertex`]
+    pub fn builder() -> PartialVertex {
+        PartialVertex::default()
     }
 
     /// Construct an instance of `Vertex`

From c35292856522c579c566084acb86f3cf7e67f1c7 Mon Sep 17 00:00:00 2001
From: Hanno Braun <hanno@braun-odw.eu>
Date: Thu, 22 Sep 2022 12:52:29 +0200
Subject: [PATCH 05/26] Rename `Vertex::builder` to `Vertex::partial`

---
 crates/fj-kernel/src/algorithms/sweep/vertex.rs | 2 +-
 crates/fj-kernel/src/builder/vertex.rs          | 2 +-
 crates/fj-kernel/src/objects/vertex.rs          | 2 +-
 3 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/crates/fj-kernel/src/algorithms/sweep/vertex.rs b/crates/fj-kernel/src/algorithms/sweep/vertex.rs
index 51f53f29b..7de75d8c0 100644
--- a/crates/fj-kernel/src/algorithms/sweep/vertex.rs
+++ b/crates/fj-kernel/src/algorithms/sweep/vertex.rs
@@ -161,7 +161,7 @@ mod tests {
 
         let surface = Surface::xz_plane();
         let curve = Curve::builder(&stores, surface).build_u_axis();
-        let vertex = Vertex::builder()
+        let vertex = Vertex::partial()
             .with_position([0.])
             .with_curve(curve)
             .build();
diff --git a/crates/fj-kernel/src/builder/vertex.rs b/crates/fj-kernel/src/builder/vertex.rs
index 191f58e93..418558bd4 100644
--- a/crates/fj-kernel/src/builder/vertex.rs
+++ b/crates/fj-kernel/src/builder/vertex.rs
@@ -4,7 +4,7 @@ use crate::objects::{Curve, GlobalVertex, Surface, SurfaceVertex, Vertex};
 
 /// API for building a [`Vertex`]
 ///
-/// Also see [`Vertex::builder`].
+/// Also see [`Vertex::partial`].
 #[derive(Default)]
 pub struct PartialVertex {
     /// The position of the [`Vertex`] on the [`Curve`]
diff --git a/crates/fj-kernel/src/objects/vertex.rs b/crates/fj-kernel/src/objects/vertex.rs
index f93d57688..62a81f204 100644
--- a/crates/fj-kernel/src/objects/vertex.rs
+++ b/crates/fj-kernel/src/objects/vertex.rs
@@ -22,7 +22,7 @@ pub struct Vertex {
 
 impl Vertex {
     /// Build a `Vertex` using [`PartialVertex`]
-    pub fn builder() -> PartialVertex {
+    pub fn partial() -> PartialVertex {
         PartialVertex::default()
     }
 

From f4faa09c39f367c6e4a1d34b9d17a1e6ece9fc68 Mon Sep 17 00:00:00 2001
From: Hanno Braun <hanno@braun-odw.eu>
Date: Thu, 22 Sep 2022 12:43:42 +0200
Subject: [PATCH 06/26] Update doc comments

---
 crates/fj-kernel/src/builder/cycle.rs  | 2 +-
 crates/fj-kernel/src/builder/vertex.rs | 6 ++++++
 crates/fj-kernel/src/objects/vertex.rs | 5 ++++-
 3 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/crates/fj-kernel/src/builder/cycle.rs b/crates/fj-kernel/src/builder/cycle.rs
index a31a333f3..346caef0a 100644
--- a/crates/fj-kernel/src/builder/cycle.rs
+++ b/crates/fj-kernel/src/builder/cycle.rs
@@ -83,7 +83,7 @@ impl<'a> CycleBuilder<'a> {
         self
     }
 
-    /// Create a polygon from a list of points
+    /// Finish building the [`Cycle`]
     pub fn build(self) -> Cycle {
         Cycle::new(self.surface, self.half_edges)
     }
diff --git a/crates/fj-kernel/src/builder/vertex.rs b/crates/fj-kernel/src/builder/vertex.rs
index 418558bd4..8993e6a4a 100644
--- a/crates/fj-kernel/src/builder/vertex.rs
+++ b/crates/fj-kernel/src/builder/vertex.rs
@@ -8,9 +8,15 @@ use crate::objects::{Curve, GlobalVertex, Surface, SurfaceVertex, Vertex};
 #[derive(Default)]
 pub struct PartialVertex {
     /// The position of the [`Vertex`] on the [`Curve`]
+    ///
+    /// Must be provided to the builder before [`PartialVertex::build`] is
+    /// called.
     pub position: Option<Point<1>>,
 
     /// The curve that the [`Vertex`] is defined in
+    ///
+    /// Must be provided to the builder before [`PartialVertex::build`] is
+    /// called.
     pub curve: Option<Curve>,
 
     /// The surface form of the [`Vertex`]
diff --git a/crates/fj-kernel/src/objects/vertex.rs b/crates/fj-kernel/src/objects/vertex.rs
index 62a81f204..da980353f 100644
--- a/crates/fj-kernel/src/objects/vertex.rs
+++ b/crates/fj-kernel/src/objects/vertex.rs
@@ -21,7 +21,10 @@ pub struct Vertex {
 }
 
 impl Vertex {
-    /// Build a `Vertex` using [`PartialVertex`]
+    /// Create a [`PartialVertex`]
+    ///
+    /// This function exists just for convenience, and will just return a
+    /// default [`PartialVertex`].
     pub fn partial() -> PartialVertex {
         PartialVertex::default()
     }

From d2ed3de0fad15286811fcdc518f49c416a18541c Mon Sep 17 00:00:00 2001
From: Hanno Braun <hanno@braun-odw.eu>
Date: Thu, 22 Sep 2022 13:21:03 +0200
Subject: [PATCH 07/26] Move `PartialVertex` to new `partial` module

---
 crates/fj-kernel/src/builder/mod.rs    |  2 +-
 crates/fj-kernel/src/builder/vertex.rs | 79 +-----------------------
 crates/fj-kernel/src/lib.rs            |  1 +
 crates/fj-kernel/src/objects/vertex.rs |  5 +-
 crates/fj-kernel/src/partial/mod.rs    | 29 +++++++++
 crates/fj-kernel/src/partial/vertex.rs | 83 ++++++++++++++++++++++++++
 6 files changed, 118 insertions(+), 81 deletions(-)
 create mode 100644 crates/fj-kernel/src/partial/mod.rs
 create mode 100644 crates/fj-kernel/src/partial/vertex.rs

diff --git a/crates/fj-kernel/src/builder/mod.rs b/crates/fj-kernel/src/builder/mod.rs
index e003cb264..cfcf754ab 100644
--- a/crates/fj-kernel/src/builder/mod.rs
+++ b/crates/fj-kernel/src/builder/mod.rs
@@ -17,5 +17,5 @@ pub use self::{
     shell::ShellBuilder,
     sketch::SketchBuilder,
     solid::SolidBuilder,
-    vertex::{GlobalVertexBuilder, PartialVertex, SurfaceVertexBuilder},
+    vertex::{GlobalVertexBuilder, SurfaceVertexBuilder},
 };
diff --git a/crates/fj-kernel/src/builder/vertex.rs b/crates/fj-kernel/src/builder/vertex.rs
index 8993e6a4a..8d7c7aa65 100644
--- a/crates/fj-kernel/src/builder/vertex.rs
+++ b/crates/fj-kernel/src/builder/vertex.rs
@@ -1,83 +1,6 @@
 use fj_math::Point;
 
-use crate::objects::{Curve, GlobalVertex, Surface, SurfaceVertex, Vertex};
-
-/// API for building a [`Vertex`]
-///
-/// Also see [`Vertex::partial`].
-#[derive(Default)]
-pub struct PartialVertex {
-    /// The position of the [`Vertex`] on the [`Curve`]
-    ///
-    /// Must be provided to the builder before [`PartialVertex::build`] is
-    /// called.
-    pub position: Option<Point<1>>,
-
-    /// The curve that the [`Vertex`] is defined in
-    ///
-    /// Must be provided to the builder before [`PartialVertex::build`] is
-    /// called.
-    pub curve: Option<Curve>,
-
-    /// The surface form of the [`Vertex`]
-    ///
-    /// Can be provided to the builder, if already available, or computed from
-    /// the position on the [`Curve`].
-    pub surface_form: Option<SurfaceVertex>,
-
-    /// The global form of the [`Vertex`]
-    ///
-    /// Can be provided to the builder, if already available, or acquired
-    /// through the surface form.
-    pub global_form: Option<GlobalVertex>,
-}
-
-impl PartialVertex {
-    /// Build the [`Vertex`] with the provided position
-    pub fn with_position(mut self, position: impl Into<Point<1>>) -> Self {
-        self.position = Some(position.into());
-        self
-    }
-
-    /// Build the [`Vertex`] with the provided curve
-    pub fn with_curve(mut self, curve: Curve) -> Self {
-        self.curve = Some(curve);
-        self
-    }
-
-    /// Build the [`Vertex`] with the provided surface form
-    pub fn with_surface_form(mut self, surface_form: SurfaceVertex) -> Self {
-        self.surface_form = Some(surface_form);
-        self
-    }
-
-    /// Build the [`Vertex`] with the provided global form
-    pub fn with_global_form(mut self, global_form: GlobalVertex) -> Self {
-        self.global_form = Some(global_form);
-        self
-    }
-
-    /// Finish building the [`Vertex`]
-    pub fn build(self) -> Vertex {
-        let position = self
-            .position
-            .expect("Cant' build `Vertex` without position");
-        let curve = self.curve.expect("Can't build `Vertex` without `Curve`");
-
-        let surface_form = self.surface_form.unwrap_or_else(|| {
-            SurfaceVertexBuilder {
-                position: curve.path().point_from_path_coords(position),
-                surface: *curve.surface(),
-                global_form: self.global_form,
-            }
-            .build()
-        });
-
-        let global_form = *surface_form.global_form();
-
-        Vertex::new(position, curve, surface_form, global_form)
-    }
-}
+use crate::objects::{Curve, GlobalVertex, Surface, SurfaceVertex};
 
 /// API for building a [`SurfaceVertex`]
 ///
diff --git a/crates/fj-kernel/src/lib.rs b/crates/fj-kernel/src/lib.rs
index 7342e23f1..da162ba61 100644
--- a/crates/fj-kernel/src/lib.rs
+++ b/crates/fj-kernel/src/lib.rs
@@ -91,5 +91,6 @@ pub mod algorithms;
 pub mod builder;
 pub mod iter;
 pub mod objects;
+pub mod partial;
 pub mod path;
 pub mod stores;
diff --git a/crates/fj-kernel/src/objects/vertex.rs b/crates/fj-kernel/src/objects/vertex.rs
index da980353f..6bffd7b47 100644
--- a/crates/fj-kernel/src/objects/vertex.rs
+++ b/crates/fj-kernel/src/objects/vertex.rs
@@ -1,8 +1,9 @@
 use fj_math::Point;
 use pretty_assertions::assert_eq;
 
-use crate::builder::{
-    GlobalVertexBuilder, PartialVertex, SurfaceVertexBuilder,
+use crate::{
+    builder::{GlobalVertexBuilder, SurfaceVertexBuilder},
+    partial::PartialVertex,
 };
 
 use super::{Curve, Surface};
diff --git a/crates/fj-kernel/src/partial/mod.rs b/crates/fj-kernel/src/partial/mod.rs
new file mode 100644
index 000000000..5e8a75aee
--- /dev/null
+++ b/crates/fj-kernel/src/partial/mod.rs
@@ -0,0 +1,29 @@
+//! Partial objects
+//!
+//! This module contains type that represent partial objects. This is useful
+//! when building objects, as it's often possible to provide just some the data
+//! they own or objects they reference, while computing the rest.
+//!
+//! More generally speaking, there are situations where different parts of a new
+//! objects are available at different times, and provided from different
+//! places. Partial objects can be used to represent such partially constructed
+//! objects whenever that is required.
+//!
+//! The API for partial objects follows a specific style:
+//!
+//! - Partial objects are structs with fields that mirror the fields of the full
+//!   object structs, but all fields are optional.
+//! - Partial object structs implement [`Default`], but a `partial` method is
+//!   also available on the respective full object struct, as a perhaps more
+//!   convenient and readable way to construct a partial object.
+//! - Partial object structs have `with_*` methods to provide values for each of
+//!   their fields.
+//! - Partial object structs may have `as_*` methods, if one or more of their
+//!   fields can be initialized by providing some alternative data.
+//! - Partial object structs have a `build` method to build a full object.
+//! - All `with_*`, `as_*`, and `build` methods can be chained, to provide a
+//!   convenient API.
+
+mod vertex;
+
+pub use self::vertex::PartialVertex;
diff --git a/crates/fj-kernel/src/partial/vertex.rs b/crates/fj-kernel/src/partial/vertex.rs
new file mode 100644
index 000000000..9ce8a495e
--- /dev/null
+++ b/crates/fj-kernel/src/partial/vertex.rs
@@ -0,0 +1,83 @@
+use fj_math::Point;
+
+use crate::{
+    builder::SurfaceVertexBuilder,
+    objects::{Curve, GlobalVertex, SurfaceVertex, Vertex},
+};
+
+/// API for building a [`Vertex`]
+///
+/// Also see [`Vertex::partial`].
+#[derive(Default)]
+pub struct PartialVertex {
+    /// The position of the [`Vertex`] on the [`Curve`]
+    ///
+    /// Must be provided to the builder before [`PartialVertex::build`] is
+    /// called.
+    pub position: Option<Point<1>>,
+
+    /// The curve that the [`Vertex`] is defined in
+    ///
+    /// Must be provided to the builder before [`PartialVertex::build`] is
+    /// called.
+    pub curve: Option<Curve>,
+
+    /// The surface form of the [`Vertex`]
+    ///
+    /// Can be provided to the builder, if already available, or computed from
+    /// the position on the [`Curve`].
+    pub surface_form: Option<SurfaceVertex>,
+
+    /// The global form of the [`Vertex`]
+    ///
+    /// Can be provided to the builder, if already available, or acquired
+    /// through the surface form.
+    pub global_form: Option<GlobalVertex>,
+}
+
+impl PartialVertex {
+    /// Build the [`Vertex`] with the provided position
+    pub fn with_position(mut self, position: impl Into<Point<1>>) -> Self {
+        self.position = Some(position.into());
+        self
+    }
+
+    /// Build the [`Vertex`] with the provided curve
+    pub fn with_curve(mut self, curve: Curve) -> Self {
+        self.curve = Some(curve);
+        self
+    }
+
+    /// Build the [`Vertex`] with the provided surface form
+    pub fn with_surface_form(mut self, surface_form: SurfaceVertex) -> Self {
+        self.surface_form = Some(surface_form);
+        self
+    }
+
+    /// Build the [`Vertex`] with the provided global form
+    pub fn with_global_form(mut self, global_form: GlobalVertex) -> Self {
+        self.global_form = Some(global_form);
+        self
+    }
+
+    /// Finish building the [`Vertex`]
+    pub fn build(self) -> Vertex {
+        let position = self
+            .position
+            .expect("Cant' build `Vertex` without position");
+        let curve = self.curve.expect("Can't build `Vertex` without `Curve`");
+
+        let surface_form = self.surface_form.unwrap_or_else(|| {
+            SurfaceVertexBuilder {
+                position: curve.path().point_from_path_coords(position),
+                surface: *curve.surface(),
+                global_form: self.global_form,
+            }
+            .build()
+        });
+
+        let global_form = *surface_form.global_form();
+
+        Vertex::new(position, curve, surface_form, global_form)
+    }
+}

From 4c5fd94fed379d2d58098f70d6a88bf34f1558b1 Mon Sep 17 00:00:00 2001
From: Hanno Braun <hanno@braun-odw.eu>
Date: Thu, 22 Sep 2022 13:30:28 +0200
Subject: [PATCH 08/26] Update doc comments

---
 crates/fj-kernel/src/partial/vertex.rs | 34 ++++++++++++++------------
 1 file changed, 19 insertions(+), 15 deletions(-)

diff --git a/crates/fj-kernel/src/partial/vertex.rs b/crates/fj-kernel/src/partial/vertex.rs
index 9ce8a495e..c92257b50 100644
--- a/crates/fj-kernel/src/partial/vertex.rs
+++ b/crates/fj-kernel/src/partial/vertex.rs
@@ -5,62 +5,66 @@ use crate::{
     objects::{Curve, GlobalVertex, SurfaceVertex, Vertex},
 };
 
-/// API for building a [`Vertex`]
+/// A partial [`Vertex`]
 ///
-/// Also see [`Vertex::partial`].
+/// See [`crate::partial`] for more information.
 #[derive(Default)]
 pub struct PartialVertex {
     /// The position of the [`Vertex`] on the [`Curve`]
     ///
-    /// Must be provided to the builder before [`PartialVertex::build`] is
-    /// called.
+    /// Must be provided before [`PartialVertex::build`] is called.
     pub position: Option<Point<1>>,
 
     /// The curve that the [`Vertex`] is defined in
     ///
-    /// Must be provided to the builder before [`PartialVertex::build`] is
-    /// called.
+    /// Must be provided before [`PartialVertex::build`] is called.
     pub curve: Option<Curve>,
 
     /// The surface form of the [`Vertex`]
     ///
-    /// Can be provided to the builder, if already available, or computed from
-    /// the position on the [`Curve`].
+    /// Can be provided, if already available, or computed from the position on
+    /// the [`Curve`].
     pub surface_form: Option<SurfaceVertex>,
 
     /// The global form of the [`Vertex`]
     ///
-    /// Can be provided to the builder, if already available, or acquired
-    /// through the surface form.
+    /// Can be provided, if already available, or acquired through the surface
+    /// form.
     pub global_form: Option<GlobalVertex>,
 }
 
 impl PartialVertex {
-    /// Build the [`Vertex`] with the provided position
+    /// Provide a position for the partial vertex
     pub fn with_position(mut self, position: impl Into<Point<1>>) -> Self {
         self.position = Some(position.into());
         self
     }
 
-    /// Build the [`Vertex`] with the provided curve
+    /// Provide a curve for the partial vertex
     pub fn with_curve(mut self, curve: Curve) -> Self {
         self.curve = Some(curve);
         self
     }
 
-    /// Build the [`Vertex`] with the provided surface form
+    /// Provide a surface form for the partial vertex
     pub fn with_surface_form(mut self, surface_form: SurfaceVertex) -> Self {
         self.surface_form = Some(surface_form);
         self
     }
 
-    /// Build the [`Vertex`] with the provided global form
+    /// Provide a global form for the partial vertex
     pub fn with_global_form(mut self, global_form: GlobalVertex) -> Self {
         self.global_form = Some(global_form);
         self
     }
 
-    /// Finish building the [`Vertex`]
+    /// Build a full [`Vertex`] from the partial vertex
+    ///
+    /// # Panics
+    ///
+    /// Panics, if no position has been provided.
+    ///
+    /// Panics, if no curve has been provided.
     pub fn build(self) -> Vertex {
         let position = self
             .position

From 795d0049ae8c532db0e2ab9c566acb794f41f8c4 Mon Sep 17 00:00:00 2001
From: Hanno Braun <hanno@braun-odw.eu>
Date: Thu, 22 Sep 2022 13:32:34 +0200
Subject: [PATCH 09/26] Rename `SurfaceVertexBuilder`

---
 crates/fj-kernel/src/builder/mod.rs    | 2 +-
 crates/fj-kernel/src/builder/vertex.rs | 4 ++--
 crates/fj-kernel/src/objects/vertex.rs | 8 ++++----
 crates/fj-kernel/src/partial/vertex.rs | 4 ++--
 4 files changed, 9 insertions(+), 9 deletions(-)

diff --git a/crates/fj-kernel/src/builder/mod.rs b/crates/fj-kernel/src/builder/mod.rs
index cfcf754ab..4c114173f 100644
--- a/crates/fj-kernel/src/builder/mod.rs
+++ b/crates/fj-kernel/src/builder/mod.rs
@@ -17,5 +17,5 @@ pub use self::{
     shell::ShellBuilder,
     sketch::SketchBuilder,
     solid::SolidBuilder,
-    vertex::{GlobalVertexBuilder, SurfaceVertexBuilder},
+    vertex::{GlobalVertexBuilder, PartialSurfaceVertex},
 };
diff --git a/crates/fj-kernel/src/builder/vertex.rs b/crates/fj-kernel/src/builder/vertex.rs
index 8d7c7aa65..11c41b7ec 100644
--- a/crates/fj-kernel/src/builder/vertex.rs
+++ b/crates/fj-kernel/src/builder/vertex.rs
@@ -5,7 +5,7 @@ use crate::objects::{Curve, GlobalVertex, Surface, SurfaceVertex};
 /// API for building a [`SurfaceVertex`]
 ///
 /// Also see [`SurfaceVertex::builder`].
-pub struct SurfaceVertexBuilder {
+pub struct PartialSurfaceVertex {
     /// The position of the [`SurfaceVertex`] on the [`Surface`]
     pub position: Point<2>,
 
@@ -19,7 +19,7 @@ pub struct SurfaceVertexBuilder {
     pub global_form: Option<GlobalVertex>,
 }
 
-impl SurfaceVertexBuilder {
+impl PartialSurfaceVertex {
     /// Build the [`SurfaceVertex`] with the provided global form
     pub fn with_global_form(mut self, global_form: GlobalVertex) -> Self {
         self.global_form = Some(global_form);
diff --git a/crates/fj-kernel/src/objects/vertex.rs b/crates/fj-kernel/src/objects/vertex.rs
index 6bffd7b47..711eaaa1d 100644
--- a/crates/fj-kernel/src/objects/vertex.rs
+++ b/crates/fj-kernel/src/objects/vertex.rs
@@ -2,7 +2,7 @@ use fj_math::Point;
 use pretty_assertions::assert_eq;
 
 use crate::{
-    builder::{GlobalVertexBuilder, SurfaceVertexBuilder},
+    builder::{GlobalVertexBuilder, PartialSurfaceVertex},
     partial::PartialVertex,
 };
 
@@ -86,12 +86,12 @@ pub struct SurfaceVertex {
 }
 
 impl SurfaceVertex {
-    /// Build a `SurfaceVertex` using [`SurfaceVertexBuilder`]
+    /// Build a `SurfaceVertex` using [`PartialSurfaceVertex`]
     pub fn builder(
         position: impl Into<Point<2>>,
         surface: Surface,
-    ) -> SurfaceVertexBuilder {
-        SurfaceVertexBuilder {
+    ) -> PartialSurfaceVertex {
+        PartialSurfaceVertex {
             position: position.into(),
             surface,
             global_form: None,
diff --git a/crates/fj-kernel/src/partial/vertex.rs b/crates/fj-kernel/src/partial/vertex.rs
index c92257b50..6ce893772 100644
--- a/crates/fj-kernel/src/partial/vertex.rs
+++ b/crates/fj-kernel/src/partial/vertex.rs
@@ -1,7 +1,7 @@
 use fj_math::Point;
 
 use crate::{
-    builder::SurfaceVertexBuilder,
+    builder::PartialSurfaceVertex,
     objects::{Curve, GlobalVertex, SurfaceVertex, Vertex},
 };
 
@@ -72,7 +72,7 @@ impl PartialVertex {
         let curve = self.curve.expect("Can't build `Vertex` without `Curve`");
 
         let surface_form = self.surface_form.unwrap_or_else(|| {
-            SurfaceVertexBuilder {
+            PartialSurfaceVertex {
                 position: curve.path().point_from_path_coords(position),
                 surface: *curve.surface(),
                 global_form: self.global_form,

From a832d3acb02ab422b4a2c21af51f39ea82df703a Mon Sep 17 00:00:00 2001
From: Hanno Braun <hanno@braun-odw.eu>
Date: Thu, 22 Sep 2022 13:33:35 +0200
Subject: [PATCH 10/26] Rename `SurfaceVertex::builder`

---
 crates/fj-kernel/src/builder/vertex.rs | 2 +-
 crates/fj-kernel/src/objects/vertex.rs | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/crates/fj-kernel/src/builder/vertex.rs b/crates/fj-kernel/src/builder/vertex.rs
index 11c41b7ec..cdc098f42 100644
--- a/crates/fj-kernel/src/builder/vertex.rs
+++ b/crates/fj-kernel/src/builder/vertex.rs
@@ -4,7 +4,7 @@ use crate::objects::{Curve, GlobalVertex, Surface, SurfaceVertex};
 
 /// API for building a [`SurfaceVertex`]
 ///
-/// Also see [`SurfaceVertex::builder`].
+/// Also see [`SurfaceVertex::partial`].
 pub struct PartialSurfaceVertex {
     /// The position of the [`SurfaceVertex`] on the [`Surface`]
     pub position: Point<2>,
diff --git a/crates/fj-kernel/src/objects/vertex.rs b/crates/fj-kernel/src/objects/vertex.rs
index 711eaaa1d..4d64845e5 100644
--- a/crates/fj-kernel/src/objects/vertex.rs
+++ b/crates/fj-kernel/src/objects/vertex.rs
@@ -87,7 +87,7 @@ pub struct SurfaceVertex {
 
 impl SurfaceVertex {
     /// Build a `SurfaceVertex` using [`PartialSurfaceVertex`]
-    pub fn builder(
+    pub fn partial(
         position: impl Into<Point<2>>,
         surface: Surface,
     ) -> PartialSurfaceVertex {

From c5929ab418ad2d2c29c2dbe17bca7859ae0e45c7 Mon Sep 17 00:00:00 2001
From: Hanno Braun <hanno@braun-odw.eu>
Date: Thu, 22 Sep 2022 13:36:33 +0200
Subject: [PATCH 11/26] Make `Surface` of `PartialSurfaceVertex` optional

---
 crates/fj-kernel/src/builder/vertex.rs | 16 +++++++++++++---
 crates/fj-kernel/src/objects/vertex.rs |  7 ++-----
 crates/fj-kernel/src/partial/vertex.rs |  2 +-
 3 files changed, 16 insertions(+), 9 deletions(-)

diff --git a/crates/fj-kernel/src/builder/vertex.rs b/crates/fj-kernel/src/builder/vertex.rs
index cdc098f42..4802d045c 100644
--- a/crates/fj-kernel/src/builder/vertex.rs
+++ b/crates/fj-kernel/src/builder/vertex.rs
@@ -10,7 +10,7 @@ pub struct PartialSurfaceVertex {
     pub position: Point<2>,
 
     /// The surface that the [`SurfaceVertex`] is defined in
-    pub surface: Surface,
+    pub surface: Option<Surface>,
 
     /// The global form of the [`SurfaceVertex`]
     ///
@@ -20,6 +20,12 @@ pub struct PartialSurfaceVertex {
 }
 
 impl PartialSurfaceVertex {
+    /// Provide a surface for the partial surface vertex
+    pub fn with_surface(mut self, surface: Surface) -> Self {
+        self.surface = Some(surface);
+        self
+    }
+
     /// Build the [`SurfaceVertex`] with the provided global form
     pub fn with_global_form(mut self, global_form: GlobalVertex) -> Self {
         self.global_form = Some(global_form);
@@ -28,12 +34,16 @@ impl PartialSurfaceVertex {
 
     /// Finish building the [`SurfaceVertex`]
     pub fn build(self) -> SurfaceVertex {
+        let surface = self
+            .surface
+            .expect("Can't build `SurfaceVertex` without `Surface`");
+
         let global_form = self.global_form.unwrap_or_else(|| {
             GlobalVertex::builder()
-                .build_from_surface_and_position(&self.surface, self.position)
+                .build_from_surface_and_position(&surface, self.position)
         });
 
-        SurfaceVertex::new(self.position, self.surface, global_form)
+        SurfaceVertex::new(self.position, surface, global_form)
     }
 }
 
diff --git a/crates/fj-kernel/src/objects/vertex.rs b/crates/fj-kernel/src/objects/vertex.rs
index 4d64845e5..57f5aa0b7 100644
--- a/crates/fj-kernel/src/objects/vertex.rs
+++ b/crates/fj-kernel/src/objects/vertex.rs
@@ -87,13 +87,10 @@ pub struct SurfaceVertex {
 
 impl SurfaceVertex {
     /// Build a `SurfaceVertex` using [`PartialSurfaceVertex`]
-    pub fn partial(
-        position: impl Into<Point<2>>,
-        surface: Surface,
-    ) -> PartialSurfaceVertex {
+    pub fn partial(position: impl Into<Point<2>>) -> PartialSurfaceVertex {
         PartialSurfaceVertex {
             position: position.into(),
-            surface,
+            surface: None,
             global_form: None,
         }
     }
diff --git a/crates/fj-kernel/src/partial/vertex.rs b/crates/fj-kernel/src/partial/vertex.rs
index 6ce893772..43595fc7a 100644
--- a/crates/fj-kernel/src/partial/vertex.rs
+++ b/crates/fj-kernel/src/partial/vertex.rs
@@ -74,7 +74,7 @@ impl PartialVertex {
         let surface_form = self.surface_form.unwrap_or_else(|| {
             PartialSurfaceVertex {
                 position: curve.path().point_from_path_coords(position),
-                surface: *curve.surface(),
+                surface: Some(*curve.surface()),
                 global_form: self.global_form,
             }
             .build()

From 454da2c2fdd36fc3c05e520c32c7cdff073d161b Mon Sep 17 00:00:00 2001
From: Hanno Braun <hanno@braun-odw.eu>
Date: Thu, 22 Sep 2022 13:39:18 +0200
Subject: [PATCH 12/26] Make position of `PartialSurfaceVertex` optional

---
 crates/fj-kernel/src/builder/vertex.rs | 15 ++++++++++++---
 crates/fj-kernel/src/objects/vertex.rs |  4 ++--
 crates/fj-kernel/src/partial/vertex.rs |  2 +-
 3 files changed, 15 insertions(+), 6 deletions(-)

diff --git a/crates/fj-kernel/src/builder/vertex.rs b/crates/fj-kernel/src/builder/vertex.rs
index 4802d045c..ba7c6bc41 100644
--- a/crates/fj-kernel/src/builder/vertex.rs
+++ b/crates/fj-kernel/src/builder/vertex.rs
@@ -7,7 +7,7 @@ use crate::objects::{Curve, GlobalVertex, Surface, SurfaceVertex};
 /// Also see [`SurfaceVertex::partial`].
 pub struct PartialSurfaceVertex {
     /// The position of the [`SurfaceVertex`] on the [`Surface`]
-    pub position: Point<2>,
+    pub position: Option<Point<2>>,
 
     /// The surface that the [`SurfaceVertex`] is defined in
     pub surface: Option<Surface>,
@@ -20,6 +20,12 @@ pub struct PartialSurfaceVertex {
 }
 
 impl PartialSurfaceVertex {
+    /// Provide a position for the partial surface vertex
+    pub fn with_position(mut self, position: impl Into<Point<2>>) -> Self {
+        self.position = Some(position.into());
+        self
+    }
+
     /// Provide a surface for the partial surface vertex
     pub fn with_surface(mut self, surface: Surface) -> Self {
         self.surface = Some(surface);
@@ -34,16 +40,19 @@ impl PartialSurfaceVertex {
 
     /// Finish building the [`SurfaceVertex`]
     pub fn build(self) -> SurfaceVertex {
+        let position = self
+            .position
+            .expect("Can't build `SurfaceVertex` without position");
         let surface = self
             .surface
             .expect("Can't build `SurfaceVertex` without `Surface`");
 
         let global_form = self.global_form.unwrap_or_else(|| {
             GlobalVertex::builder()
-                .build_from_surface_and_position(&surface, self.position)
+                .build_from_surface_and_position(&surface, position)
         });
 
-        SurfaceVertex::new(self.position, surface, global_form)
+        SurfaceVertex::new(position, surface, global_form)
     }
 }
 
diff --git a/crates/fj-kernel/src/objects/vertex.rs b/crates/fj-kernel/src/objects/vertex.rs
index 57f5aa0b7..ec0876716 100644
--- a/crates/fj-kernel/src/objects/vertex.rs
+++ b/crates/fj-kernel/src/objects/vertex.rs
@@ -87,9 +87,9 @@ pub struct SurfaceVertex {
 
 impl SurfaceVertex {
     /// Build a `SurfaceVertex` using [`PartialSurfaceVertex`]
-    pub fn partial(position: impl Into<Point<2>>) -> PartialSurfaceVertex {
+    pub fn partial() -> PartialSurfaceVertex {
         PartialSurfaceVertex {
-            position: position.into(),
+            position: None,
             surface: None,
             global_form: None,
         }
diff --git a/crates/fj-kernel/src/partial/vertex.rs b/crates/fj-kernel/src/partial/vertex.rs
index 43595fc7a..13118227e 100644
--- a/crates/fj-kernel/src/partial/vertex.rs
+++ b/crates/fj-kernel/src/partial/vertex.rs
@@ -73,7 +73,7 @@ impl PartialVertex {
 
         let surface_form = self.surface_form.unwrap_or_else(|| {
             PartialSurfaceVertex {
-                position: curve.path().point_from_path_coords(position),
+                position: Some(curve.path().point_from_path_coords(position)),
                 surface: Some(*curve.surface()),
                 global_form: self.global_form,
             }

From 254d45854413b0e48ad7adab55a424cc97c54a9e Mon Sep 17 00:00:00 2001
From: Hanno Braun <hanno@braun-odw.eu>
Date: Thu, 22 Sep 2022 13:40:28 +0200
Subject: [PATCH 13/26] Derive `Default` for `PartialSurfaceVertex`

---
 crates/fj-kernel/src/builder/vertex.rs | 1 +
 crates/fj-kernel/src/objects/vertex.rs | 6 +-----
 2 files changed, 2 insertions(+), 5 deletions(-)

diff --git a/crates/fj-kernel/src/builder/vertex.rs b/crates/fj-kernel/src/builder/vertex.rs
index ba7c6bc41..87c0c58c1 100644
--- a/crates/fj-kernel/src/builder/vertex.rs
+++ b/crates/fj-kernel/src/builder/vertex.rs
@@ -5,6 +5,7 @@ use crate::objects::{Curve, GlobalVertex, Surface, SurfaceVertex};
 /// API for building a [`SurfaceVertex`]
 ///
 /// Also see [`SurfaceVertex::partial`].
+#[derive(Default)]
 pub struct PartialSurfaceVertex {
     /// The position of the [`SurfaceVertex`] on the [`Surface`]
     pub position: Option<Point<2>>,
diff --git a/crates/fj-kernel/src/objects/vertex.rs b/crates/fj-kernel/src/objects/vertex.rs
index ec0876716..0401c61cc 100644
--- a/crates/fj-kernel/src/objects/vertex.rs
+++ b/crates/fj-kernel/src/objects/vertex.rs
@@ -88,11 +88,7 @@ pub struct SurfaceVertex {
 impl SurfaceVertex {
     /// Build a `SurfaceVertex` using [`PartialSurfaceVertex`]
     pub fn partial() -> PartialSurfaceVertex {
-        PartialSurfaceVertex {
-            position: None,
-            surface: None,
-            global_form: None,
-        }
+        PartialSurfaceVertex::default()
     }
 
     /// Construct a new instance of `SurfaceVertex`

From 26e2f6431a5b7219a493201eae63389d2f62f19e Mon Sep 17 00:00:00 2001
From: Hanno Braun <hanno@braun-odw.eu>
Date: Thu, 22 Sep 2022 13:44:22 +0200
Subject: [PATCH 14/26] Update documentation of `PartialSurfaceVertex`

---
 crates/fj-kernel/src/builder/vertex.rs | 24 +++++++++++++++++-------
 crates/fj-kernel/src/objects/vertex.rs |  5 ++++-
 2 files changed, 21 insertions(+), 8 deletions(-)

diff --git a/crates/fj-kernel/src/builder/vertex.rs b/crates/fj-kernel/src/builder/vertex.rs
index 87c0c58c1..4be114fd9 100644
--- a/crates/fj-kernel/src/builder/vertex.rs
+++ b/crates/fj-kernel/src/builder/vertex.rs
@@ -2,21 +2,25 @@ use fj_math::Point;
 
 use crate::objects::{Curve, GlobalVertex, Surface, SurfaceVertex};
 
-/// API for building a [`SurfaceVertex`]
+/// A partial [`SurfaceVertex`]
 ///
-/// Also see [`SurfaceVertex::partial`].
+/// See [`crate::partial`] for more information.
 #[derive(Default)]
 pub struct PartialSurfaceVertex {
-    /// The position of the [`SurfaceVertex`] on the [`Surface`]
+    /// The position of the [`SurfaceVertex`] in the [`Surface`]
+    ///
+    /// Must be provided before [`PartialSurfaceVertex::build`] is called.
     pub position: Option<Point<2>>,
 
     /// The surface that the [`SurfaceVertex`] is defined in
+    ///
+    /// Must be provided before [`PartialSurfaceVertex::build`] is called.
     pub surface: Option<Surface>,
 
     /// The global form of the [`SurfaceVertex`]
     ///
-    /// Can be provided to the builder, if already available, or computed from
-    /// the position on the [`Surface`].
+    /// Can be provided, if already available, or computed from the position on
+    /// the [`Surface`].
     pub global_form: Option<GlobalVertex>,
 }
 
@@ -33,13 +37,19 @@ impl PartialSurfaceVertex {
         self
     }
 
-    /// Build the [`SurfaceVertex`] with the provided global form
+    /// Provide a global form for the partial surface vertex
     pub fn with_global_form(mut self, global_form: GlobalVertex) -> Self {
         self.global_form = Some(global_form);
         self
     }
 
-    /// Finish building the [`SurfaceVertex`]
+    /// Build a full [`SurfaceVertex`] from the partial surface vertex
+    ///
+    /// # Panics
+    ///
+    /// Panics, if no position has been provided.
+    ///
+    /// Panics, if no surface has been provided.
     pub fn build(self) -> SurfaceVertex {
         let position = self
             .position
diff --git a/crates/fj-kernel/src/objects/vertex.rs b/crates/fj-kernel/src/objects/vertex.rs
index 0401c61cc..fe00e62af 100644
--- a/crates/fj-kernel/src/objects/vertex.rs
+++ b/crates/fj-kernel/src/objects/vertex.rs
@@ -86,7 +86,10 @@ pub struct SurfaceVertex {
 }
 
 impl SurfaceVertex {
-    /// Build a `SurfaceVertex` using [`PartialSurfaceVertex`]
+    /// Create a [`PartialSurfaceVertex`]
+    ///
+    /// This function exists just for convenience, and will just return a
+    /// default [`PartialSurfaceVertex`].
     pub fn partial() -> PartialSurfaceVertex {
         PartialSurfaceVertex::default()
     }

From 3a2dffe909beb544386193e151eb88487cef5223 Mon Sep 17 00:00:00 2001
From: Hanno Braun <hanno@braun-odw.eu>
Date: Thu, 22 Sep 2022 13:45:59 +0200
Subject: [PATCH 15/26] Move `PartialSurfaceVertex` to `partial` module

---
 crates/fj-kernel/src/builder/mod.rs    |  2 +-
 crates/fj-kernel/src/builder/vertex.rs | 67 +-----------------------
 crates/fj-kernel/src/objects/vertex.rs |  4 +-
 crates/fj-kernel/src/partial/mod.rs    |  2 +-
 crates/fj-kernel/src/partial/vertex.rs | 70 ++++++++++++++++++++++++--
 5 files changed, 71 insertions(+), 74 deletions(-)

diff --git a/crates/fj-kernel/src/builder/mod.rs b/crates/fj-kernel/src/builder/mod.rs
index 4c114173f..688b09087 100644
--- a/crates/fj-kernel/src/builder/mod.rs
+++ b/crates/fj-kernel/src/builder/mod.rs
@@ -17,5 +17,5 @@ pub use self::{
     shell::ShellBuilder,
     sketch::SketchBuilder,
     solid::SolidBuilder,
-    vertex::{GlobalVertexBuilder, PartialSurfaceVertex},
+    vertex::GlobalVertexBuilder,
 };
diff --git a/crates/fj-kernel/src/builder/vertex.rs b/crates/fj-kernel/src/builder/vertex.rs
index 4be114fd9..3f9bafea2 100644
--- a/crates/fj-kernel/src/builder/vertex.rs
+++ b/crates/fj-kernel/src/builder/vertex.rs
@@ -1,71 +1,6 @@
 use fj_math::Point;
 
-use crate::objects::{Curve, GlobalVertex, Surface, SurfaceVertex};
-
-/// A partial [`SurfaceVertex`]
-///
-/// See [`crate::partial`] for more information.
-#[derive(Default)]
-pub struct PartialSurfaceVertex {
-    /// The position of the [`SurfaceVertex`] in the [`Surface`]
-    ///
-    /// Must be provided before [`PartialSurfaceVertex::build`] is called.
-    pub position: Option<Point<2>>,
-
-    /// The surface that the [`SurfaceVertex`] is defined in
-    ///
-    /// Must be provided before [`PartialSurfaceVertex::build`] is called.
-    pub surface: Option<Surface>,
-
-    /// The global form of the [`SurfaceVertex`]
-    ///
-    /// Can be provided, if already available, or computed from the position on
-    /// the [`Surface`].
-    pub global_form: Option<GlobalVertex>,
-}
-
-impl PartialSurfaceVertex {
-    /// Provide a position for the partial surface vertex
-    pub fn with_position(mut self, position: impl Into<Point<2>>) -> Self {
-        self.position = Some(position.into());
-        self
-    }
-
-    /// Provide a surface for the partial surface vertex
-    pub fn with_surface(mut self, surface: Surface) -> Self {
-        self.surface = Some(surface);
-        self
-    }
-
-    /// Provide a global form for the partial surface vertex
-    pub fn with_global_form(mut self, global_form: GlobalVertex) -> Self {
-        self.global_form = Some(global_form);
-        self
-    }
-
-    /// Build a full [`SurfaceVertex`] from the partial surface vertex
-    ///
-    /// # Panics
-    ///
-    /// Panics, if no position has been provided.
-    ///
-    /// Panics, if no surface has been provided.
-    pub fn build(self) -> SurfaceVertex {
-        let position = self
-            .position
-            .expect("Can't build `SurfaceVertex` without position");
-        let surface = self
-            .surface
-            .expect("Can't build `SurfaceVertex` without `Surface`");
-
-        let global_form = self.global_form.unwrap_or_else(|| {
-            GlobalVertex::builder()
-                .build_from_surface_and_position(&surface, position)
-        });
-
-        SurfaceVertex::new(position, surface, global_form)
-    }
-}
+use crate::objects::{Curve, GlobalVertex, Surface};
 
 /// API for building a [`GlobalVertex`]
 ///
diff --git a/crates/fj-kernel/src/objects/vertex.rs b/crates/fj-kernel/src/objects/vertex.rs
index fe00e62af..32749c308 100644
--- a/crates/fj-kernel/src/objects/vertex.rs
+++ b/crates/fj-kernel/src/objects/vertex.rs
@@ -2,8 +2,8 @@ use fj_math::Point;
 use pretty_assertions::assert_eq;
 
 use crate::{
-    builder::{GlobalVertexBuilder, PartialSurfaceVertex},
-    partial::PartialVertex,
+    builder::GlobalVertexBuilder,
+    partial::{PartialSurfaceVertex, PartialVertex},
 };
 
 use super::{Curve, Surface};
diff --git a/crates/fj-kernel/src/partial/mod.rs b/crates/fj-kernel/src/partial/mod.rs
index 5e8a75aee..d6ea119a6 100644
--- a/crates/fj-kernel/src/partial/mod.rs
+++ b/crates/fj-kernel/src/partial/mod.rs
@@ -26,4 +26,4 @@
 
 mod vertex;
 
-pub use self::vertex::PartialVertex;
+pub use self::vertex::{PartialSurfaceVertex, PartialVertex};
diff --git a/crates/fj-kernel/src/partial/vertex.rs b/crates/fj-kernel/src/partial/vertex.rs
index 13118227e..0ce000abd 100644
--- a/crates/fj-kernel/src/partial/vertex.rs
+++ b/crates/fj-kernel/src/partial/vertex.rs
@@ -1,9 +1,6 @@
 use fj_math::Point;
 
-use crate::{
-    builder::PartialSurfaceVertex,
-    objects::{Curve, GlobalVertex, SurfaceVertex, Vertex},
-};
+use crate::objects::{Curve, GlobalVertex, Surface, SurfaceVertex, Vertex};
 
 /// A partial [`Vertex`]
 ///
@@ -85,3 +82,68 @@ impl PartialVertex {
         Vertex::new(position, curve, surface_form, global_form)
     }
 }
+
+/// A partial [`SurfaceVertex`]
+///
+/// See [`crate::partial`] for more information.
+#[derive(Default)]
+pub struct PartialSurfaceVertex {
+    /// The position of the [`SurfaceVertex`] in the [`Surface`]
+    ///
+    /// Must be provided before [`PartialSurfaceVertex::build`] is called.
+    pub position: Option<Point<2>>,
+
+    /// The surface that the [`SurfaceVertex`] is defined in
+    ///
+    /// Must be provided before [`PartialSurfaceVertex::build`] is called.
+    pub surface: Option<Surface>,
+
+    /// The global form of the [`SurfaceVertex`]
+    ///
+    /// Can be provided, if already available, or computed from the position on
+    /// the [`Surface`].
+    pub global_form: Option<GlobalVertex>,
+}
+
+impl PartialSurfaceVertex {
+    /// Provide a position for the partial surface vertex
+    pub fn with_position(mut self, position: impl Into<Point<2>>) -> Self {
+        self.position = Some(position.into());
+        self
+    }
+
+    /// Provide a surface for the partial surface vertex
+    pub fn with_surface(mut self, surface: Surface) -> Self {
+        self.surface = Some(surface);
+        self
+    }
+
+    /// Provide a global form for the partial surface vertex
+    pub fn with_global_form(mut self, global_form: GlobalVertex) -> Self {
+        self.global_form = Some(global_form);
+        self
+    }
+
+    /// Build a full [`SurfaceVertex`] from the partial surface vertex
+    ///
+    /// # Panics
+    ///
+    /// Panics, if no position has been provided.
+    ///
+    /// Panics, if no surface has been provided.
+    pub fn build(self) -> SurfaceVertex {
+        let position = self
+            .position
+            .expect("Can't build `SurfaceVertex` without position");
+        let surface = self
+            .surface
+            .expect("Can't build `SurfaceVertex` without `Surface`");
+
+        let global_form = self.global_form.unwrap_or_else(|| {
+            GlobalVertex::builder()
+                .build_from_surface_and_position(&surface, position)
+        });
+
+        SurfaceVertex::new(position, surface, global_form)
+    }
+}

From b0eaedda2cba686f63ee3ea36765749d46011467 Mon Sep 17 00:00:00 2001
From: Hanno Braun <hanno@braun-odw.eu>
Date: Thu, 22 Sep 2022 13:51:06 +0200
Subject: [PATCH 16/26] Move `self` into `GlobalVertexBuilder` methods

---
 crates/fj-kernel/src/builder/vertex.rs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/crates/fj-kernel/src/builder/vertex.rs b/crates/fj-kernel/src/builder/vertex.rs
index 3f9bafea2..10953b299 100644
--- a/crates/fj-kernel/src/builder/vertex.rs
+++ b/crates/fj-kernel/src/builder/vertex.rs
@@ -10,7 +10,7 @@ pub struct GlobalVertexBuilder;
 impl GlobalVertexBuilder {
     /// Build a [`GlobalVertex`] from a curve and a position on that curve
     pub fn build_from_curve_and_position(
-        &self,
+        self,
         curve: &Curve,
         position: impl Into<Point<1>>,
     ) -> GlobalVertex {
@@ -20,7 +20,7 @@ impl GlobalVertexBuilder {
 
     /// Build a [`GlobalVertex`] from a surface and a position on that surface
     pub fn build_from_surface_and_position(
-        &self,
+        self,
         surface: &Surface,
         position: impl Into<Point<2>>,
     ) -> GlobalVertex {

From d308729d1a0590a82f7b173808dc0b1bf0b9e45e Mon Sep 17 00:00:00 2001
From: Hanno Braun <hanno@braun-odw.eu>
Date: Thu, 22 Sep 2022 14:04:18 +0200
Subject: [PATCH 17/26] Derive `Default` for `GlobalVertexBuilder`

---
 crates/fj-kernel/src/builder/vertex.rs | 1 +
 crates/fj-kernel/src/objects/vertex.rs | 2 +-
 2 files changed, 2 insertions(+), 1 deletion(-)

diff --git a/crates/fj-kernel/src/builder/vertex.rs b/crates/fj-kernel/src/builder/vertex.rs
index 10953b299..16730deec 100644
--- a/crates/fj-kernel/src/builder/vertex.rs
+++ b/crates/fj-kernel/src/builder/vertex.rs
@@ -5,6 +5,7 @@ use crate::objects::{Curve, GlobalVertex, Surface};
 /// API for building a [`GlobalVertex`]
 ///
 /// Also see [`GlobalVertex::builder`].
+#[derive(Default)]
 pub struct GlobalVertexBuilder;
 
 impl GlobalVertexBuilder {
diff --git a/crates/fj-kernel/src/objects/vertex.rs b/crates/fj-kernel/src/objects/vertex.rs
index 32749c308..bde10ec12 100644
--- a/crates/fj-kernel/src/objects/vertex.rs
+++ b/crates/fj-kernel/src/objects/vertex.rs
@@ -150,7 +150,7 @@ pub struct GlobalVertex {
 impl GlobalVertex {
     /// Build a `GlobalVertex` using [`GlobalVertexBuilder`]
     pub fn builder() -> GlobalVertexBuilder {
-        GlobalVertexBuilder
+        GlobalVertexBuilder::default()
     }
 
     /// Construct a `GlobalVertex` from a point

From 24be0e55a3b402a1dbfd18c24b6dcbc0ca88022e Mon Sep 17 00:00:00 2001
From: Hanno Braun <hanno@braun-odw.eu>
Date: Thu, 22 Sep 2022 14:07:55 +0200
Subject: [PATCH 18/26] Add full builder API to `GlobalVertexBuilder`

---
 crates/fj-kernel/src/builder/vertex.rs | 20 +++++++++++++++++++-
 1 file changed, 19 insertions(+), 1 deletion(-)

diff --git a/crates/fj-kernel/src/builder/vertex.rs b/crates/fj-kernel/src/builder/vertex.rs
index 16730deec..1bf21871f 100644
--- a/crates/fj-kernel/src/builder/vertex.rs
+++ b/crates/fj-kernel/src/builder/vertex.rs
@@ -6,9 +6,18 @@ use crate::objects::{Curve, GlobalVertex, Surface};
 ///
 /// Also see [`GlobalVertex::builder`].
 #[derive(Default)]
-pub struct GlobalVertexBuilder;
+pub struct GlobalVertexBuilder {
+    /// The position of the [`GlobalVertex`]
+    pub position: Option<Point<3>>,
+}
 
 impl GlobalVertexBuilder {
+    /// Provide a position
+    pub fn with_position(mut self, position: impl Into<Point<3>>) -> Self {
+        self.position = Some(position.into());
+        self
+    }
+
     /// Build a [`GlobalVertex`] from a curve and a position on that curve
     pub fn build_from_curve_and_position(
         self,
@@ -28,4 +37,13 @@ impl GlobalVertexBuilder {
         let position = surface.point_from_surface_coords(position);
         GlobalVertex::from_position(position)
     }
+
+    /// Build a full [`GlobalVertex`]
+    pub fn build(self) -> GlobalVertex {
+        let position = self
+            .position
+            .expect("Can't build a `GlobalVertex` without a position");
+
+        GlobalVertex::from_position(position)
+    }
 }

From 495c5d2ef0052366f5e04f03f391c3bb0874d58d Mon Sep 17 00:00:00 2001
From: Hanno Braun <hanno@braun-odw.eu>
Date: Thu, 22 Sep 2022 14:13:37 +0200
Subject: [PATCH 19/26] Replace `GlobalVertexBuilder` method

---
 crates/fj-kernel/src/builder/edge.rs   |  3 ++-
 crates/fj-kernel/src/builder/vertex.rs | 13 +++++++------
 crates/fj-kernel/src/partial/vertex.rs |  3 ++-
 3 files changed, 11 insertions(+), 8 deletions(-)

diff --git a/crates/fj-kernel/src/builder/edge.rs b/crates/fj-kernel/src/builder/edge.rs
index 707b8965c..812df9658 100644
--- a/crates/fj-kernel/src/builder/edge.rs
+++ b/crates/fj-kernel/src/builder/edge.rs
@@ -99,7 +99,8 @@ impl<'a> HalfEdgeBuilder<'a> {
 
         let global_vertices = points.map(|position| {
             GlobalVertex::builder()
-                .build_from_surface_and_position(&self.surface, position)
+                .from_surface_and_position(&self.surface, position)
+                .build()
         });
 
         let surface_vertices = {
diff --git a/crates/fj-kernel/src/builder/vertex.rs b/crates/fj-kernel/src/builder/vertex.rs
index 1bf21871f..42a22d180 100644
--- a/crates/fj-kernel/src/builder/vertex.rs
+++ b/crates/fj-kernel/src/builder/vertex.rs
@@ -25,17 +25,18 @@ impl GlobalVertexBuilder {
         position: impl Into<Point<1>>,
     ) -> GlobalVertex {
         let position_surface = curve.path().point_from_path_coords(position);
-        self.build_from_surface_and_position(curve.surface(), position_surface)
+        self.from_surface_and_position(curve.surface(), position_surface)
+            .build()
     }
 
     /// Build a [`GlobalVertex`] from a surface and a position on that surface
-    pub fn build_from_surface_and_position(
-        self,
+    pub fn from_surface_and_position(
+        mut self,
         surface: &Surface,
         position: impl Into<Point<2>>,
-    ) -> GlobalVertex {
-        let position = surface.point_from_surface_coords(position);
-        GlobalVertex::from_position(position)
+    ) -> Self {
+        self.position = Some(surface.point_from_surface_coords(position));
+        self
     }
 
     /// Build a full [`GlobalVertex`]
diff --git a/crates/fj-kernel/src/partial/vertex.rs b/crates/fj-kernel/src/partial/vertex.rs
index 0ce000abd..33fc6b622 100644
--- a/crates/fj-kernel/src/partial/vertex.rs
+++ b/crates/fj-kernel/src/partial/vertex.rs
@@ -141,7 +141,8 @@ impl PartialSurfaceVertex {
 
         let global_form = self.global_form.unwrap_or_else(|| {
             GlobalVertex::builder()
-                .build_from_surface_and_position(&surface, position)
+                .from_surface_and_position(&surface, position)
+                .build()
         });
 
         SurfaceVertex::new(position, surface, global_form)

From aa8de0520d87f41bee849f9d0bf9ce7fe6be9b61 Mon Sep 17 00:00:00 2001
From: Hanno Braun <hanno@braun-odw.eu>
Date: Thu, 22 Sep 2022 14:16:01 +0200
Subject: [PATCH 20/26] Replace `GlobalVertexBuilder` method

---
 crates/fj-kernel/src/builder/edge.rs   | 3 ++-
 crates/fj-kernel/src/builder/vertex.rs | 5 ++---
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/crates/fj-kernel/src/builder/edge.rs b/crates/fj-kernel/src/builder/edge.rs
index 812df9658..3d7c1791e 100644
--- a/crates/fj-kernel/src/builder/edge.rs
+++ b/crates/fj-kernel/src/builder/edge.rs
@@ -61,7 +61,8 @@ impl<'a> HalfEdgeBuilder<'a> {
                 [Scalar::ZERO, Scalar::TAU].map(|coord| Point::from([coord]));
 
             let global_vertex = GlobalVertex::builder()
-                .build_from_curve_and_position(&curve, a_curve);
+                .from_curve_and_position(&curve, a_curve)
+                .build();
 
             let surface_vertices = [a_curve, b_curve].map(|point_curve| {
                 let point_surface =
diff --git a/crates/fj-kernel/src/builder/vertex.rs b/crates/fj-kernel/src/builder/vertex.rs
index 42a22d180..da9a9804c 100644
--- a/crates/fj-kernel/src/builder/vertex.rs
+++ b/crates/fj-kernel/src/builder/vertex.rs
@@ -19,14 +19,13 @@ impl GlobalVertexBuilder {
     }
 
     /// Build a [`GlobalVertex`] from a curve and a position on that curve
-    pub fn build_from_curve_and_position(
+    pub fn from_curve_and_position(
         self,
         curve: &Curve,
         position: impl Into<Point<1>>,
-    ) -> GlobalVertex {
+    ) -> Self {
         let position_surface = curve.path().point_from_path_coords(position);
         self.from_surface_and_position(curve.surface(), position_surface)
-            .build()
     }
 
     /// Build a [`GlobalVertex`] from a surface and a position on that surface

From f46edfc45ab7dd290902ba061c6e8196c6d333a0 Mon Sep 17 00:00:00 2001
From: Hanno Braun <hanno@braun-odw.eu>
Date: Thu, 22 Sep 2022 14:16:52 +0200
Subject: [PATCH 21/26] Rename `GlobalVertexBuilder`

---
 crates/fj-kernel/src/builder/mod.rs    | 2 +-
 crates/fj-kernel/src/builder/vertex.rs | 4 ++--
 crates/fj-kernel/src/objects/vertex.rs | 8 ++++----
 3 files changed, 7 insertions(+), 7 deletions(-)

diff --git a/crates/fj-kernel/src/builder/mod.rs b/crates/fj-kernel/src/builder/mod.rs
index 688b09087..ae45ffc5a 100644
--- a/crates/fj-kernel/src/builder/mod.rs
+++ b/crates/fj-kernel/src/builder/mod.rs
@@ -17,5 +17,5 @@ pub use self::{
     shell::ShellBuilder,
     sketch::SketchBuilder,
     solid::SolidBuilder,
-    vertex::GlobalVertexBuilder,
+    vertex::PartialGlobalVertex,
 };
diff --git a/crates/fj-kernel/src/builder/vertex.rs b/crates/fj-kernel/src/builder/vertex.rs
index da9a9804c..775755869 100644
--- a/crates/fj-kernel/src/builder/vertex.rs
+++ b/crates/fj-kernel/src/builder/vertex.rs
@@ -6,12 +6,12 @@ use crate::objects::{Curve, GlobalVertex, Surface};
 ///
 /// Also see [`GlobalVertex::builder`].
 #[derive(Default)]
-pub struct GlobalVertexBuilder {
+pub struct PartialGlobalVertex {
     /// The position of the [`GlobalVertex`]
     pub position: Option<Point<3>>,
 }
 
-impl GlobalVertexBuilder {
+impl PartialGlobalVertex {
     /// Provide a position
     pub fn with_position(mut self, position: impl Into<Point<3>>) -> Self {
         self.position = Some(position.into());
diff --git a/crates/fj-kernel/src/objects/vertex.rs b/crates/fj-kernel/src/objects/vertex.rs
index bde10ec12..1a3ca9d06 100644
--- a/crates/fj-kernel/src/objects/vertex.rs
+++ b/crates/fj-kernel/src/objects/vertex.rs
@@ -2,7 +2,7 @@ use fj_math::Point;
 use pretty_assertions::assert_eq;
 
 use crate::{
-    builder::GlobalVertexBuilder,
+    builder::PartialGlobalVertex,
     partial::{PartialSurfaceVertex, PartialVertex},
 };
 
@@ -148,9 +148,9 @@ pub struct GlobalVertex {
 }
 
 impl GlobalVertex {
-    /// Build a `GlobalVertex` using [`GlobalVertexBuilder`]
-    pub fn builder() -> GlobalVertexBuilder {
-        GlobalVertexBuilder::default()
+    /// Build a `GlobalVertex` using [`PartialGlobalVertex`]
+    pub fn builder() -> PartialGlobalVertex {
+        PartialGlobalVertex::default()
     }
 
     /// Construct a `GlobalVertex` from a point

From e7649d2470a3bdddf2160c828163338d54e38323 Mon Sep 17 00:00:00 2001
From: Hanno Braun <hanno@braun-odw.eu>
Date: Thu, 22 Sep 2022 14:19:09 +0200
Subject: [PATCH 22/26] Rename `GlobalVertex::builder`

---
 crates/fj-kernel/src/builder/edge.rs   | 4 ++--
 crates/fj-kernel/src/builder/vertex.rs | 2 +-
 crates/fj-kernel/src/objects/vertex.rs | 2 +-
 crates/fj-kernel/src/partial/vertex.rs | 2 +-
 4 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/crates/fj-kernel/src/builder/edge.rs b/crates/fj-kernel/src/builder/edge.rs
index 3d7c1791e..335cb50a6 100644
--- a/crates/fj-kernel/src/builder/edge.rs
+++ b/crates/fj-kernel/src/builder/edge.rs
@@ -60,7 +60,7 @@ impl<'a> HalfEdgeBuilder<'a> {
             let [a_curve, b_curve] =
                 [Scalar::ZERO, Scalar::TAU].map(|coord| Point::from([coord]));
 
-            let global_vertex = GlobalVertex::builder()
+            let global_vertex = GlobalVertex::partial()
                 .from_curve_and_position(&curve, a_curve)
                 .build();
 
@@ -99,7 +99,7 @@ impl<'a> HalfEdgeBuilder<'a> {
         let points = points.map(Into::into);
 
         let global_vertices = points.map(|position| {
-            GlobalVertex::builder()
+            GlobalVertex::partial()
                 .from_surface_and_position(&self.surface, position)
                 .build()
         });
diff --git a/crates/fj-kernel/src/builder/vertex.rs b/crates/fj-kernel/src/builder/vertex.rs
index 775755869..3631e974a 100644
--- a/crates/fj-kernel/src/builder/vertex.rs
+++ b/crates/fj-kernel/src/builder/vertex.rs
@@ -4,7 +4,7 @@ use crate::objects::{Curve, GlobalVertex, Surface};
 
 /// API for building a [`GlobalVertex`]
 ///
-/// Also see [`GlobalVertex::builder`].
+/// Also see [`GlobalVertex::partial`].
 #[derive(Default)]
 pub struct PartialGlobalVertex {
     /// The position of the [`GlobalVertex`]
diff --git a/crates/fj-kernel/src/objects/vertex.rs b/crates/fj-kernel/src/objects/vertex.rs
index 1a3ca9d06..53a629577 100644
--- a/crates/fj-kernel/src/objects/vertex.rs
+++ b/crates/fj-kernel/src/objects/vertex.rs
@@ -149,7 +149,7 @@ pub struct GlobalVertex {
 
 impl GlobalVertex {
     /// Build a `GlobalVertex` using [`PartialGlobalVertex`]
-    pub fn builder() -> PartialGlobalVertex {
+    pub fn partial() -> PartialGlobalVertex {
         PartialGlobalVertex::default()
     }
 
diff --git a/crates/fj-kernel/src/partial/vertex.rs b/crates/fj-kernel/src/partial/vertex.rs
index 33fc6b622..0788b96d3 100644
--- a/crates/fj-kernel/src/partial/vertex.rs
+++ b/crates/fj-kernel/src/partial/vertex.rs
@@ -140,7 +140,7 @@ impl PartialSurfaceVertex {
             .expect("Can't build `SurfaceVertex` without `Surface`");
 
         let global_form = self.global_form.unwrap_or_else(|| {
-            GlobalVertex::builder()
+            GlobalVertex::partial()
                 .from_surface_and_position(&surface, position)
                 .build()
         });

From 3aa041ad65217af7ddce48fb22db6360e582fba6 Mon Sep 17 00:00:00 2001
From: Hanno Braun <hanno@braun-odw.eu>
Date: Thu, 22 Sep 2022 14:22:02 +0200
Subject: [PATCH 23/26] Update documentation of `PartialGlobalVertex`

---
 crates/fj-kernel/src/builder/vertex.rs | 14 ++++++++------
 crates/fj-kernel/src/objects/vertex.rs |  5 ++++-
 2 files changed, 12 insertions(+), 7 deletions(-)

diff --git a/crates/fj-kernel/src/builder/vertex.rs b/crates/fj-kernel/src/builder/vertex.rs
index 3631e974a..fc9dd98e8 100644
--- a/crates/fj-kernel/src/builder/vertex.rs
+++ b/crates/fj-kernel/src/builder/vertex.rs
@@ -2,23 +2,25 @@ use fj_math::Point;
 
 use crate::objects::{Curve, GlobalVertex, Surface};
 
-/// API for building a [`GlobalVertex`]
+/// A partial [`GlobalVertex`]
 ///
-/// Also see [`GlobalVertex::partial`].
+/// See [`crate::partial`] for more information.
 #[derive(Default)]
 pub struct PartialGlobalVertex {
     /// The position of the [`GlobalVertex`]
+    ///
+    /// Must be provided before [`PartialGlobalVertex::build`] is called.
     pub position: Option<Point<3>>,
 }
 
 impl PartialGlobalVertex {
-    /// Provide a position
+    /// Provide a position for the partial global vertex
     pub fn with_position(mut self, position: impl Into<Point<3>>) -> Self {
         self.position = Some(position.into());
         self
     }
 
-    /// Build a [`GlobalVertex`] from a curve and a position on that curve
+    /// Update partial global vertex from the given curve and position on it
     pub fn from_curve_and_position(
         self,
         curve: &Curve,
@@ -28,7 +30,7 @@ impl PartialGlobalVertex {
         self.from_surface_and_position(curve.surface(), position_surface)
     }
 
-    /// Build a [`GlobalVertex`] from a surface and a position on that surface
+    /// Update partial global vertex from the given surface and position on it
     pub fn from_surface_and_position(
         mut self,
         surface: &Surface,
@@ -38,7 +40,7 @@ impl PartialGlobalVertex {
         self
     }
 
-    /// Build a full [`GlobalVertex`]
+    /// Build a full [`GlobalVertex`] from the partial global vertex
     pub fn build(self) -> GlobalVertex {
         let position = self
             .position
diff --git a/crates/fj-kernel/src/objects/vertex.rs b/crates/fj-kernel/src/objects/vertex.rs
index 53a629577..39e0e4d55 100644
--- a/crates/fj-kernel/src/objects/vertex.rs
+++ b/crates/fj-kernel/src/objects/vertex.rs
@@ -148,7 +148,10 @@ pub struct GlobalVertex {
 }
 
 impl GlobalVertex {
-    /// Build a `GlobalVertex` using [`PartialGlobalVertex`]
+    /// Create a [`PartialGlobalVertex`]
+    ///
+    /// This function exists just for convenience, and will just return a
+    /// default [`PartialGlobalVertex`].
     pub fn partial() -> PartialGlobalVertex {
         PartialGlobalVertex::default()
     }

From c16c5db713ba3706dec028a4a4185f1ade3e3ef8 Mon Sep 17 00:00:00 2001
From: Hanno Braun <hanno@braun-odw.eu>
Date: Thu, 22 Sep 2022 14:22:23 +0200
Subject: [PATCH 24/26] Update doc comment

---
 crates/fj-kernel/src/objects/vertex.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/crates/fj-kernel/src/objects/vertex.rs b/crates/fj-kernel/src/objects/vertex.rs
index 39e0e4d55..5c86aa018 100644
--- a/crates/fj-kernel/src/objects/vertex.rs
+++ b/crates/fj-kernel/src/objects/vertex.rs
@@ -156,7 +156,7 @@ impl GlobalVertex {
         PartialGlobalVertex::default()
     }
 
-    /// Construct a `GlobalVertex` from a point
+    /// Construct a `GlobalVertex` from a position
     pub fn from_position(position: impl Into<Point<3>>) -> Self {
         let position = position.into();
         Self { position }

From b7b3671fef33421dd85632abab2fb8f0cb84f186 Mon Sep 17 00:00:00 2001
From: Hanno Braun <hanno@braun-odw.eu>
Date: Thu, 22 Sep 2022 14:24:09 +0200
Subject: [PATCH 25/26] Move `PartialGlobalVertex` to `partial` module

---
 crates/fj-kernel/src/builder/mod.rs    |  2 -
 crates/fj-kernel/src/builder/vertex.rs | 51 --------------------------
 crates/fj-kernel/src/objects/vertex.rs |  5 +--
 crates/fj-kernel/src/partial/mod.rs    |  4 +-
 crates/fj-kernel/src/partial/vertex.rs | 48 ++++++++++++++++++++++++
 5 files changed, 53 insertions(+), 57 deletions(-)
 delete mode 100644 crates/fj-kernel/src/builder/vertex.rs

diff --git a/crates/fj-kernel/src/builder/mod.rs b/crates/fj-kernel/src/builder/mod.rs
index ae45ffc5a..680d3fff0 100644
--- a/crates/fj-kernel/src/builder/mod.rs
+++ b/crates/fj-kernel/src/builder/mod.rs
@@ -7,7 +7,6 @@ mod face;
 mod shell;
 mod sketch;
 mod solid;
-mod vertex;
 
 pub use self::{
     curve::{CurveBuilder, GlobalCurveBuilder},
@@ -17,5 +16,4 @@ pub use self::{
     shell::ShellBuilder,
     sketch::SketchBuilder,
     solid::SolidBuilder,
-    vertex::PartialGlobalVertex,
 };
diff --git a/crates/fj-kernel/src/builder/vertex.rs b/crates/fj-kernel/src/builder/vertex.rs
deleted file mode 100644
index fc9dd98e8..000000000
--- a/crates/fj-kernel/src/builder/vertex.rs
+++ /dev/null
@@ -1,51 +0,0 @@
-use fj_math::Point;
-
-use crate::objects::{Curve, GlobalVertex, Surface};
-
-/// A partial [`GlobalVertex`]
-///
-/// See [`crate::partial`] for more information.
-#[derive(Default)]
-pub struct PartialGlobalVertex {
-    /// The position of the [`GlobalVertex`]
-    ///
-    /// Must be provided before [`PartialGlobalVertex::build`] is called.
-    pub position: Option<Point<3>>,
-}
-
-impl PartialGlobalVertex {
-    /// Provide a position for the partial global vertex
-    pub fn with_position(mut self, position: impl Into<Point<3>>) -> Self {
-        self.position = Some(position.into());
-        self
-    }
-
-    /// Update partial global vertex from the given curve and position on it
-    pub fn from_curve_and_position(
-        self,
-        curve: &Curve,
-        position: impl Into<Point<1>>,
-    ) -> Self {
-        let position_surface = curve.path().point_from_path_coords(position);
-        self.from_surface_and_position(curve.surface(), position_surface)
-    }
-
-    /// Update partial global vertex from the given surface and position on it
-    pub fn from_surface_and_position(
-        mut self,
-        surface: &Surface,
-        position: impl Into<Point<2>>,
-    ) -> Self {
-        self.position = Some(surface.point_from_surface_coords(position));
-        self
-    }
-
-    /// Build a full [`GlobalVertex`] from the partial global vertex
-    pub fn build(self) -> GlobalVertex {
-        let position = self
-            .position
-            .expect("Can't build a `GlobalVertex` without a position");
-
-        GlobalVertex::from_position(position)
-    }
-}
diff --git a/crates/fj-kernel/src/objects/vertex.rs b/crates/fj-kernel/src/objects/vertex.rs
index 5c86aa018..19710976f 100644
--- a/crates/fj-kernel/src/objects/vertex.rs
+++ b/crates/fj-kernel/src/objects/vertex.rs
@@ -1,9 +1,8 @@
 use fj_math::Point;
 use pretty_assertions::assert_eq;
 
-use crate::{
-    builder::PartialGlobalVertex,
-    partial::{PartialSurfaceVertex, PartialVertex},
+use crate::partial::{
+    PartialGlobalVertex, PartialSurfaceVertex, PartialVertex,
 };
 
 use super::{Curve, Surface};
diff --git a/crates/fj-kernel/src/partial/mod.rs b/crates/fj-kernel/src/partial/mod.rs
index d6ea119a6..ccab2ca10 100644
--- a/crates/fj-kernel/src/partial/mod.rs
+++ b/crates/fj-kernel/src/partial/mod.rs
@@ -26,4 +26,6 @@
 
 mod vertex;
 
-pub use self::vertex::{PartialSurfaceVertex, PartialVertex};
+pub use self::vertex::{
+    PartialGlobalVertex, PartialSurfaceVertex, PartialVertex,
+};
diff --git a/crates/fj-kernel/src/partial/vertex.rs b/crates/fj-kernel/src/partial/vertex.rs
index 0788b96d3..80f61cfc0 100644
--- a/crates/fj-kernel/src/partial/vertex.rs
+++ b/crates/fj-kernel/src/partial/vertex.rs
@@ -148,3 +148,51 @@ impl PartialSurfaceVertex {
         SurfaceVertex::new(position, surface, global_form)
     }
 }
+
+/// A partial [`GlobalVertex`]
+///
+/// See [`crate::partial`] for more information.
+#[derive(Default)]
+pub struct PartialGlobalVertex {
+    /// The position of the [`GlobalVertex`]
+    ///
+    /// Must be provided before [`PartialGlobalVertex::build`] is called.
+    pub position: Option<Point<3>>,
+}
+
+impl PartialGlobalVertex {
+    /// Provide a position for the partial global vertex
+    pub fn with_position(mut self, position: impl Into<Point<3>>) -> Self {
+        self.position = Some(position.into());
+        self
+    }
+
+    /// Update partial global vertex from the given curve and position on it
+    pub fn from_curve_and_position(
+        self,
+        curve: &Curve,
+        position: impl Into<Point<1>>,
+    ) -> Self {
+        let position_surface = curve.path().point_from_path_coords(position);
+        self.from_surface_and_position(curve.surface(), position_surface)
+    }
+
+    /// Update partial global vertex from the given surface and position on it
+    pub fn from_surface_and_position(
+        mut self,
+        surface: &Surface,
+        position: impl Into<Point<2>>,
+    ) -> Self {
+        self.position = Some(surface.point_from_surface_coords(position));
+        self
+    }
+
+    /// Build a full [`GlobalVertex`] from the partial global vertex
+    pub fn build(self) -> GlobalVertex {
+        let position = self
+            .position
+            .expect("Can't build a `GlobalVertex` without a position");
+
+        GlobalVertex::from_position(position)
+    }
+}

From 1f62fa61eb625f9968a332dbec4787d8c1d1e874 Mon Sep 17 00:00:00 2001
From: Hanno Braun <hanno@braun-odw.eu>
Date: Thu, 22 Sep 2022 14:25:56 +0200
Subject: [PATCH 26/26] Update doc comment

---
 crates/fj-kernel/src/partial/mod.rs | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/crates/fj-kernel/src/partial/mod.rs b/crates/fj-kernel/src/partial/mod.rs
index ccab2ca10..70f138d6a 100644
--- a/crates/fj-kernel/src/partial/mod.rs
+++ b/crates/fj-kernel/src/partial/mod.rs
@@ -18,8 +18,9 @@
 //!   convenient and readable way to construct a partial object.
 //! - Partial object structs have `with_*` methods to provide values for each of
 //!   their fields.
-//! - Partial object structs may have `as_*` methods, if one or more of their
-//!   fields can be initialized by providing some alternative data.
+//! - Partial object structs may have other methods with prefixes like `as_*`,
+//!   `from_*`, or similar, if one or more of their fields can be initialized by
+//!   providing alternative data.
 //! - Partial object structs have a `build` method to build a full object.
 //! - All `with_*`, `as_*`, and `build` methods can be chained, to provide a
 //!   convenient API.