8 files changed, 13 insertions, 13 deletions
diff --git a/src/library/layout/align.rs b/src/library/layout/align.rs
index 0c758cf2..705d555b 100644
--- a/src/library/layout/align.rs
+++ b/src/library/layout/align.rs
@@ -28,7 +28,7 @@ impl AlignNode {
 impl Layout for AlignNode {
     fn layout(
         &self,
-        world: &dyn World,
+        world: Tracked<dyn World>,
         regions: &Regions,
         styles: StyleChain,
     ) -> SourceResult<Vec<Frame>> {
diff --git a/src/library/layout/columns.rs b/src/library/layout/columns.rs
index e0163f63..8ae4394e 100644
--- a/src/library/layout/columns.rs
+++ b/src/library/layout/columns.rs
@@ -28,7 +28,7 @@ impl ColumnsNode {
 impl Layout for ColumnsNode {
     fn layout(
         &self,
-        world: &dyn World,
+        world: Tracked<dyn World>,
         regions: &Regions,
         styles: StyleChain,
     ) -> SourceResult<Vec<Frame>> {
diff --git a/src/library/layout/flow.rs b/src/library/layout/flow.rs
index 05c10789..7cb52910 100644
--- a/src/library/layout/flow.rs
+++ b/src/library/layout/flow.rs
@@ -25,7 +25,7 @@ pub enum FlowChild {
 impl Layout for FlowNode {
     fn layout(
         &self,
-        world: &dyn World,
+        world: Tracked<dyn World>,
         regions: &Regions,
         styles: StyleChain,
     ) -> SourceResult<Vec<Frame>> {
@@ -149,7 +149,7 @@ impl FlowLayouter {
     /// Layout a node.
     pub fn layout_node(
         &mut self,
-        world: &dyn World,
+        world: Tracked<dyn World>,
         node: &LayoutNode,
         styles: StyleChain,
     ) -> SourceResult<()> {
diff --git a/src/library/layout/grid.rs b/src/library/layout/grid.rs
index cd4fc6b4..2c246df9 100644
--- a/src/library/layout/grid.rs
+++ b/src/library/layout/grid.rs
@@ -33,7 +33,7 @@ impl GridNode {
 impl Layout for GridNode {
     fn layout(
         &self,
-        world: &dyn World,
+        world: Tracked<dyn World>,
         regions: &Regions,
         styles: StyleChain,
     ) -> SourceResult<Vec<Frame>> {
@@ -93,7 +93,7 @@ castable! {
 /// Performs grid layout.
 pub struct GridLayouter<'a> {
     /// The core context.
-    world: &'a dyn World,
+    world: Tracked<'a, dyn World>,
     /// The grid cells.
     cells: &'a [LayoutNode],
     /// The column tracks including gutter tracks.
@@ -133,7 +133,7 @@ impl<'a> GridLayouter<'a> {
     ///
     /// This prepares grid layout by unifying content and gutter tracks.
     pub fn new(
-        world: &'a dyn World,
+        world: Tracked<'a, dyn World>,
         tracks: Spec<&[TrackSizing]>,
         gutter: Spec<&[TrackSizing]>,
         cells: &'a [LayoutNode],
diff --git a/src/library/layout/pad.rs b/src/library/layout/pad.rs
index 983bfa11..06c3672f 100644
--- a/src/library/layout/pad.rs
+++ b/src/library/layout/pad.rs
@@ -28,7 +28,7 @@ impl PadNode {
 impl Layout for PadNode {
     fn layout(
         &self,
-        world: &dyn World,
+        world: Tracked<dyn World>,
         regions: &Regions,
         styles: StyleChain,
     ) -> SourceResult<Vec<Frame>> {
diff --git a/src/library/layout/page.rs b/src/library/layout/page.rs
index ba597263..9cbbcca5 100644
--- a/src/library/layout/page.rs
+++ b/src/library/layout/page.rs
@@ -57,7 +57,7 @@ impl PageNode {
     /// Layout the page run into a sequence of frames, one per page.
     pub fn layout(
         &self,
-        world: &dyn World,
+        world: Tracked<dyn World>,
         mut page: usize,
         styles: StyleChain,
     ) -> SourceResult<Vec<Frame>> {
@@ -180,7 +180,7 @@ impl Marginal {
     /// Resolve the marginal based on the page number.
     pub fn resolve(
         &self,
-        world: &dyn World,
+        world: Tracked<dyn World>,
         page: usize,
     ) -> SourceResult<Option<Content>> {
         Ok(match self {
diff --git a/src/library/layout/place.rs b/src/library/layout/place.rs
index 862c969e..01da62e5 100644
--- a/src/library/layout/place.rs
+++ b/src/library/layout/place.rs
@@ -21,7 +21,7 @@ impl PlaceNode {
 impl Layout for PlaceNode {
     fn layout(
         &self,
-        world: &dyn World,
+        world: Tracked<dyn World>,
         regions: &Regions,
         styles: StyleChain,
     ) -> SourceResult<Vec<Frame>> {
diff --git a/src/library/layout/stack.rs b/src/library/layout/stack.rs
index a9fc1621..b9a26642 100644
--- a/src/library/layout/stack.rs
+++ b/src/library/layout/stack.rs
@@ -27,7 +27,7 @@ impl StackNode {
 impl Layout for StackNode {
     fn layout(
         &self,
-        world: &dyn World,
+        world: Tracked<dyn World>,
         regions: &Regions,
         styles: StyleChain,
     ) -> SourceResult<Vec<Frame>> {
@@ -168,7 +168,7 @@ impl<'a> StackLayouter<'a> {
     /// Layout an arbitrary node.
     pub fn layout_node(
         &mut self,
-        world: &dyn World,
+        world: Tracked<dyn World>,
         node: &LayoutNode,
         styles: StyleChain,
     ) -> SourceResult<()> {