diff --git a/src/autorouter/ratsnest.rs b/src/autorouter/ratsnest.rs
index ba3ef1a..2f66f96 100644
--- a/src/autorouter/ratsnest.rs
+++ b/src/autorouter/ratsnest.rs
@@ -114,7 +114,7 @@ impl Ratsnest {
             }
 
             for zone in layout.layer_zone_nodes(layer) {
-                if let Some(net) = layout.drawing().compound_weight(zone).maybe_net() {
+                if let Some(net) = layout.drawing().compound_weight(zone.into()).maybe_net() {
                     if !triangulations.contains_key(&(layer, net)) {
                         triangulations.insert(
                             (layer, net),
diff --git a/src/autorouter/selection.rs b/src/autorouter/selection.rs
index ff49aef..b76f58d 100644
--- a/src/autorouter/selection.rs
+++ b/src/autorouter/selection.rs
@@ -5,8 +5,9 @@ use serde::{Deserialize, Serialize};
 use crate::{
     board::{mesadata::MesadataTrait, Board},
     drawing::graph::{GetLayer, MakePrimitive, PrimitiveIndex},
-    graph::GenericIndex,
-    layout::NodeIndex,
+    geometry::compound::CompoundManagerTrait,
+    graph::{GenericIndex, GetNodeIndex},
+    layout::{zone::ZoneWeight, CompoundWeight, NodeIndex},
 };
 
 #[derive(Debug, Clone, Hash, Eq, PartialEq, Serialize, Deserialize)]
@@ -64,7 +65,17 @@ impl Selection {
             NodeIndex::Primitive(primitive) => {
                 primitive.primitive(board.layout().drawing()).layer()
             }
-            NodeIndex::Compound(compound) => board.layout().zone(compound).layer(),
+            NodeIndex::Compound(compound) => {
+                if let CompoundWeight::Zone(..) = board.layout().drawing().compound_weight(compound)
+                {
+                    board
+                        .layout()
+                        .zone(GenericIndex::<ZoneWeight>::new(compound.node_index()))
+                        .layer()
+                } else {
+                    unreachable!()
+                }
+            }
         };
 
         if let (Some(pinname), Some(layername)) = (
diff --git a/src/bin/topola-egui/app.rs b/src/bin/topola-egui/app.rs
index 16f1c3f..b1aa631 100644
--- a/src/bin/topola-egui/app.rs
+++ b/src/bin/topola-egui/app.rs
@@ -386,7 +386,7 @@ impl eframe::App for App {
                         for zone in board.layout().layer_zone_nodes(1) {
                             let color = if overlay
                                 .selection()
-                                .contains_node(board, GenericNode::Compound(zone))
+                                .contains_node(board, GenericNode::Compound(zone.into()))
                             {
                                 egui::Color32::from_rgb(100, 100, 255)
                             } else {
@@ -413,7 +413,7 @@ impl eframe::App for App {
                         for zone in board.layout().layer_zone_nodes(0) {
                             let color = if overlay
                                 .selection()
-                                .contains_node(board, GenericNode::Compound(zone))
+                                .contains_node(board, GenericNode::Compound(zone.into()))
                             {
                                 egui::Color32::from_rgb(255, 100, 100)
                             } else {
diff --git a/src/bin/topola-egui/overlay.rs b/src/bin/topola-egui/overlay.rs
index 633ac21..9a0cee3 100644
--- a/src/bin/topola-egui/overlay.rs
+++ b/src/bin/topola-egui/overlay.rs
@@ -15,7 +15,11 @@ use topola::{
         compound::CompoundManagerTrait,
         shape::{Shape, ShapeTrait},
     },
-    layout::{zone::MakePolyShape, Layout, NodeIndex},
+    graph::{GenericIndex, GetNodeIndex},
+    layout::{
+        zone::{MakePolyShape, Zone, ZoneWeight},
+        CompoundWeight, Layout, NodeIndex,
+    },
 };
 
 pub struct Overlay {
@@ -72,7 +76,17 @@ impl Overlay {
             NodeIndex::Primitive(primitive) => {
                 primitive.primitive(board.layout().drawing()).shape().into()
             }
-            NodeIndex::Compound(compound) => board.layout().zone(compound).shape().into(),
+            NodeIndex::Compound(compound) => {
+                match board.layout().drawing().compound_weight(compound) {
+                    CompoundWeight::Zone(zone) => Zone::new(
+                        GenericIndex::<ZoneWeight>::new(compound.node_index()),
+                        board.layout(),
+                    )
+                    .shape()
+                    .into(),
+                    CompoundWeight::Via(via) => unreachable!(),
+                }
+            }
         };
 
         if shape.contains_point(p) {
diff --git a/src/board/board.rs b/src/board/board.rs
index 8570a85..d4d88d6 100644
--- a/src/board/board.rs
+++ b/src/board/board.rs
@@ -58,7 +58,7 @@ impl<M: MesadataTrait> Board<M> {
     ) -> Result<FixedDotIndex, Infringement> {
         let dot = self.layout.add_zone_fixed_dot(weight, zone)?;
 
-        if let Some(pin) = self.node_pinname(GenericNode::Compound(zone)) {
+        if let Some(pin) = self.node_pinname(GenericNode::Compound(zone.into())) {
             self.node_to_pinname
                 .insert(GenericNode::Primitive(dot.into()), pin.to_string());
         }
@@ -92,7 +92,7 @@ impl<M: MesadataTrait> Board<M> {
     ) -> Result<FixedSegIndex, Infringement> {
         let seg = self.layout.add_zone_fixed_seg(from, to, weight, zone)?;
 
-        if let Some(pin) = self.node_pinname(GenericNode::Compound(zone)) {
+        if let Some(pin) = self.node_pinname(GenericNode::Compound(zone.into())) {
             self.node_to_pinname
                 .insert(GenericNode::Primitive(seg.into()), pin.to_string());
         }
diff --git a/src/layout/layout.rs b/src/layout/layout.rs
index 3e6b840..ad5f42d 100644
--- a/src/layout/layout.rs
+++ b/src/layout/layout.rs
@@ -1,5 +1,6 @@
 use std::collections::HashMap;
 
+use enum_dispatch::enum_dispatch;
 use geo::Point;
 use petgraph::stable_graph::StableDiGraph;
 use rstar::AABB;
@@ -26,19 +27,29 @@ use crate::{
         GetWidth, SegWeightTrait,
     },
     graph::{GenericIndex, GetNodeIndex},
-    layout::zone::{GetMaybeApex, MakePolyShape, PourZoneIndex, SolidZoneIndex, Zone, ZoneWeight},
+    layout::{
+        via::ViaWeight,
+        zone::{GetMaybeApex, MakePolyShape, Zone, ZoneWeight},
+    },
     math::Circle,
 };
 
-pub type NodeIndex = GenericNode<PrimitiveIndex, GenericIndex<ZoneWeight>>;
+#[derive(Debug, Clone, Copy)]
+#[enum_dispatch(GetMaybeNet)]
+pub enum CompoundWeight {
+    Zone(ZoneWeight),
+    Via(ViaWeight),
+}
+
+pub type NodeIndex = GenericNode<PrimitiveIndex, GenericIndex<CompoundWeight>>;
 
 #[derive(Debug)]
 pub struct Layout<R: RulesTrait> {
-    drawing: Drawing<ZoneWeight, R>,
+    drawing: Drawing<CompoundWeight, R>,
 }
 
 impl<R: RulesTrait> Layout<R> {
-    pub fn new(drawing: Drawing<ZoneWeight, R>) -> Self {
+    pub fn new(drawing: Drawing<CompoundWeight, R>) -> Self {
         Self { drawing }
     }
 
@@ -63,6 +74,21 @@ impl<R: RulesTrait> Layout<R> {
             .insert_segbend(from, around, dot_weight, seg_weight, bend_weight, cw)
     }
 
+    pub fn add_via(&mut self, weight: ViaWeight) -> Result<GenericIndex<ViaWeight>, Infringement> {
+        let compound = self.drawing.add_compound(weight.into());
+
+        for layer in weight.from_layer..weight.to_layer {
+            let dot = self.drawing.add_fixed_dot(FixedDotWeight {
+                circle: weight.circle,
+                layer,
+                maybe_net: weight.maybe_net,
+            })?;
+            self.drawing.add_to_compound(dot, compound);
+        }
+
+        Ok(GenericIndex::<ViaWeight>::new(compound.node_index()))
+    }
+
     pub fn add_fixed_dot(&mut self, weight: FixedDotWeight) -> Result<FixedDotIndex, Infringement> {
         self.drawing.add_fixed_dot(weight)
     }
@@ -75,7 +101,7 @@ impl<R: RulesTrait> Layout<R> {
         let maybe_dot = self.drawing.add_fixed_dot(weight);
 
         if let Ok(dot) = maybe_dot {
-            self.drawing.add_to_compound(dot, zone);
+            self.drawing.add_to_compound(dot, zone.into());
         }
 
         maybe_dot
@@ -100,7 +126,7 @@ impl<R: RulesTrait> Layout<R> {
         let maybe_seg = self.add_fixed_seg(from, to, weight);
 
         if let Ok(seg) = maybe_seg {
-            self.drawing.add_to_compound(seg, zone);
+            self.drawing.add_to_compound(seg, zone.into());
         }
 
         maybe_seg
@@ -129,13 +155,17 @@ impl<R: RulesTrait> Layout<R> {
     }
 
     pub fn add_zone(&mut self, weight: ZoneWeight) -> GenericIndex<ZoneWeight> {
-        self.drawing.add_compound(weight)
+        GenericIndex::<ZoneWeight>::new(
+            self.drawing
+                .add_compound(CompoundWeight::Zone(weight))
+                .node_index(),
+        )
     }
 
     pub fn zones<W: 'static>(
         &self,
         node: GenericIndex<W>,
-    ) -> impl Iterator<Item = GenericIndex<ZoneWeight>> + '_ {
+    ) -> impl Iterator<Item = GenericIndex<CompoundWeight>> + '_ {
         self.drawing.compounds(node)
     }
 
@@ -171,11 +201,13 @@ impl<R: RulesTrait> Layout<R> {
 
     pub fn zone_nodes(&self) -> impl Iterator<Item = GenericIndex<ZoneWeight>> + '_ {
         self.drawing.rtree().iter().filter_map(|wrapper| {
-            if let NodeIndex::Compound(zone) = wrapper.data {
-                Some(zone)
-            } else {
-                None
+            if let NodeIndex::Compound(compound) = wrapper.data {
+                if let CompoundWeight::Zone(..) = self.drawing.compound_weight(compound) {
+                    return Some(GenericIndex::<ZoneWeight>::new(compound.node_index()));
+                }
             }
+
+            None
         })
     }
 
@@ -190,11 +222,13 @@ impl<R: RulesTrait> Layout<R> {
                 [f64::INFINITY, f64::INFINITY, layer as f64],
             ))
             .filter_map(|wrapper| {
-                if let NodeIndex::Compound(zone) = wrapper.data {
-                    Some(zone)
-                } else {
-                    None
+                if let NodeIndex::Compound(compound) = wrapper.data {
+                    if let CompoundWeight::Zone(..) = self.drawing.compound_weight(compound) {
+                        return Some(GenericIndex::<ZoneWeight>::new(compound.node_index()));
+                    }
                 }
+
+                None
             })
     }
 
@@ -207,7 +241,7 @@ impl<R: RulesTrait> Layout<R> {
             .compound_members(GenericIndex::new(zone.node_index()))
     }
 
-    pub fn drawing(&self) -> &Drawing<ZoneWeight, R> {
+    pub fn drawing(&self) -> &Drawing<CompoundWeight, R> {
         &self.drawing
     }
 
diff --git a/src/layout/mod.rs b/src/layout/mod.rs
index 1e5fef1..a0ea8e6 100644
--- a/src/layout/mod.rs
+++ b/src/layout/mod.rs
@@ -1,4 +1,5 @@
 mod layout;
+pub mod via;
 pub mod zone;
 
 pub use layout::*;
diff --git a/src/layout/via.rs b/src/layout/via.rs
new file mode 100644
index 0000000..3dcb7a8
--- /dev/null
+++ b/src/layout/via.rs
@@ -0,0 +1,48 @@
+use crate::{
+    drawing::{graph::GetMaybeNet, rules::RulesTrait},
+    geometry::compound::CompoundManagerTrait,
+    graph::{GenericIndex, GetNodeIndex},
+    layout::{CompoundWeight, Layout},
+    math::Circle,
+};
+
+#[derive(Debug)]
+pub struct Via<'a, R: RulesTrait> {
+    pub index: GenericIndex<ViaWeight>,
+    layout: &'a Layout<R>,
+}
+
+impl<'a, R: RulesTrait> Via<'a, R> {
+    pub fn new(index: GenericIndex<ViaWeight>, layout: &'a Layout<R>) -> Self {
+        Self { index, layout }
+    }
+}
+
+impl<'a, R: RulesTrait> GetMaybeNet for Via<'a, R> {
+    fn maybe_net(&self) -> Option<usize> {
+        self.layout
+            .drawing()
+            .compound_weight(self.index.into())
+            .maybe_net()
+    }
+}
+
+#[derive(Debug, Clone, Copy)]
+pub struct ViaWeight {
+    pub from_layer: u64,
+    pub to_layer: u64,
+    pub circle: Circle,
+    pub maybe_net: Option<usize>,
+}
+
+impl GetMaybeNet for ViaWeight {
+    fn maybe_net(&self) -> Option<usize> {
+        self.maybe_net
+    }
+}
+
+impl From<GenericIndex<ViaWeight>> for GenericIndex<CompoundWeight> {
+    fn from(via: GenericIndex<ViaWeight>) -> Self {
+        GenericIndex::<CompoundWeight>::new(via.node_index())
+    }
+}
diff --git a/src/layout/zone.rs b/src/layout/zone.rs
index a270768..75d87e0 100644
--- a/src/layout/zone.rs
+++ b/src/layout/zone.rs
@@ -14,7 +14,7 @@ use crate::{
     },
     geometry::{compound::CompoundManagerTrait, poly::PolyShape, GetPos},
     graph::{GenericIndex, GetNodeIndex},
-    layout::Layout,
+    layout::{CompoundWeight, Layout},
 };
 
 #[enum_dispatch]
@@ -52,7 +52,13 @@ impl<'a, R: RulesTrait> Zone<'a, R> {
 
 impl<'a, R: RulesTrait> GetLayer for Zone<'a, R> {
     fn layer(&self) -> u64 {
-        self.layout.drawing().compound_weight(self.index).layer()
+        if let CompoundWeight::Zone(weight) =
+            self.layout.drawing().compound_weight(self.index.into())
+        {
+            weight.layer()
+        } else {
+            unreachable!();
+        }
     }
 }
 
@@ -60,7 +66,7 @@ impl<'a, R: RulesTrait> GetMaybeNet for Zone<'a, R> {
     fn maybe_net(&self) -> Option<usize> {
         self.layout
             .drawing()
-            .compound_weight(self.index)
+            .compound_weight(self.index.into())
             .maybe_net()
     }
 }
@@ -73,7 +79,7 @@ impl<'a, R: RulesTrait> MakePolyShape for Zone<'a, R> {
                     self.layout
                         .drawing()
                         .geometry()
-                        .compound_members(self.index)
+                        .compound_members(self.index.into())
                         .filter_map(|primitive_node| {
                             let PrimitiveIndex::FixedDot(dot) = primitive_node else {
                                 return None;
@@ -104,7 +110,7 @@ impl<'a, R: RulesTrait> GetMaybeApex for Zone<'a, R> {
         self.layout
             .drawing()
             .geometry()
-            .compound_members(self.index)
+            .compound_members(self.index.into())
             .find_map(|primitive_node| {
                 if let PrimitiveIndex::FixedDot(dot) = primitive_node {
                     if self.is_apex(dot) {
@@ -124,25 +130,35 @@ pub enum ZoneWeight {
     Pour(PourZoneWeight),
 }
 
+impl From<GenericIndex<ZoneWeight>> for GenericIndex<CompoundWeight> {
+    fn from(zone: GenericIndex<ZoneWeight>) -> Self {
+        GenericIndex::<CompoundWeight>::new(zone.node_index())
+    }
+}
+
 #[derive(Debug, Clone, Copy, PartialEq)]
 pub struct SolidZoneWeight {
     pub layer: u64,
     pub maybe_net: Option<usize>,
 }
 
-impl<'a> GetLayer for SolidZoneWeight {
+impl GetLayer for SolidZoneWeight {
     fn layer(&self) -> u64 {
         self.layer
     }
 }
 
-impl<'a> GetMaybeNet for SolidZoneWeight {
+impl GetMaybeNet for SolidZoneWeight {
     fn maybe_net(&self) -> Option<usize> {
         self.maybe_net
     }
 }
 
-pub type SolidZoneIndex = GenericIndex<SolidZoneWeight>;
+impl From<GenericIndex<SolidZoneWeight>> for GenericIndex<CompoundWeight> {
+    fn from(zone: GenericIndex<SolidZoneWeight>) -> Self {
+        GenericIndex::<CompoundWeight>::new(zone.node_index())
+    }
+}
 
 #[derive(Debug, Clone, Copy, PartialEq)]
 pub struct PourZoneWeight {
@@ -162,4 +178,8 @@ impl<'a> GetMaybeNet for PourZoneWeight {
     }
 }
 
-pub type PourZoneIndex = GenericIndex<PourZoneWeight>;
+impl From<GenericIndex<PourZoneWeight>> for GenericIndex<CompoundWeight> {
+    fn from(zone: GenericIndex<PourZoneWeight>) -> Self {
+        GenericIndex::<CompoundWeight>::new(zone.node_index())
+    }
+}