diff --git a/blueprintcompiler/ast_utils.py b/blueprintcompiler/ast_utils.py
index ab692bc..5019098 100644
--- a/blueprintcompiler/ast_utils.py
+++ b/blueprintcompiler/ast_utils.py
@@ -33,7 +33,7 @@ class Children:
     def __init__(self, children):
         self._children = children
 
-    def __iter__(self):
+    def __iter__(self) -> T.Iterator["AstNode"]:
         return iter(self._children)
 
     @T.overload
@@ -175,11 +175,6 @@ class AstNode:
         for child in self.children:
             yield from child.get_semantic_tokens()
 
-    def iterate_children_recursive(self) -> T.Iterator["AstNode"]:
-        yield self
-        for child in self.children:
-            yield from child.iterate_children_recursive()
-
     def validate_unique_in_parent(self, error, check=None):
         for child in self.parent.children:
             if child is self:
@@ -270,7 +265,12 @@ class Context:
     def __get__(self, instance, owner):
         if instance is None:
             return self
-        return self.func(instance)
+        if ctx := getattr(instance, "_context_" + self.type.__name__, None):
+            return ctx
+        else:
+            ctx = self.func(instance)
+            setattr(instance, "_context_" + self.type.__name__, ctx)
+            return ctx
 
 
 def context(type: T.Type[TCtx]):
diff --git a/blueprintcompiler/language/contexts.py b/blueprintcompiler/language/contexts.py
index fec38f7..49b7b40 100644
--- a/blueprintcompiler/language/contexts.py
+++ b/blueprintcompiler/language/contexts.py
@@ -19,9 +19,44 @@
 
 import typing as T
 from dataclasses import dataclass
+from functools import cached_property
+
 from .common import *
+from .gobject_object import Object
 
 
 @dataclass
 class ValueTypeCtx:
     value_type: T.Optional[GirType]
+
+
+@dataclass
+class ScopeCtx:
+    node: AstNode
+
+    @cached_property
+    def objects(self) -> T.Dict[str, Object]:
+        return {
+            obj.tokens["id"]: obj
+            for obj in self._iter_recursive(self.node)
+            if obj.tokens["id"] is not None
+        }
+
+    def validate_unique_ids(self) -> None:
+        passed = {}
+        for obj in self._iter_recursive(self.node):
+            if obj.tokens["id"] is None:
+                continue
+
+            if obj.tokens["id"] in passed:
+                token = obj.group.tokens["id"]
+                raise CompileError(
+                    f"Duplicate object ID '{obj.tokens['id']}'", token.start, token.end
+                )
+            passed[obj.tokens["id"]] = obj
+
+    def _iter_recursive(self, node: AstNode):
+        yield node
+        for child in node.children:
+            if child.context[ScopeCtx] is self:
+                yield from self._iter_recursive(child)
diff --git a/blueprintcompiler/language/expression.py b/blueprintcompiler/language/expression.py
index 16ee33c..0cf41b0 100644
--- a/blueprintcompiler/language/expression.py
+++ b/blueprintcompiler/language/expression.py
@@ -19,7 +19,7 @@
 
 
 from .common import *
-from .contexts import ValueTypeCtx
+from .contexts import ScopeCtx, ValueTypeCtx
 from .types import TypeName
 from .gtkbuilder_template import Template
 
@@ -87,7 +87,7 @@ class LiteralExpr(Expr):
 
         return (
             isinstance(self.literal.value, IdentLiteral)
-            and self.literal.value.ident in self.root.objects_by_id
+            and self.literal.value.ident in self.context[ScopeCtx].objects
         )
 
     @property
@@ -105,7 +105,7 @@ class LiteralExpr(Expr):
         from .values import IdentLiteral
 
         if isinstance(self.literal.value, IdentLiteral):
-            if object := self.root.objects_by_id.get(self.literal.value.ident):
+            if object := self.context[ScopeCtx].objects.get(self.literal.value.ident):
                 return not isinstance(object, Template)
         return True
 
diff --git a/blueprintcompiler/language/gobject_signal.py b/blueprintcompiler/language/gobject_signal.py
index 25d789b..e5c71c6 100644
--- a/blueprintcompiler/language/gobject_signal.py
+++ b/blueprintcompiler/language/gobject_signal.py
@@ -20,6 +20,7 @@
 import typing as T
 
 from .gtkbuilder_template import Template
+from .contexts import ScopeCtx
 from .common import *
 
 
@@ -112,7 +113,7 @@ class Signal(AstNode):
         if object_id is None:
             return
 
-        if self.root.objects_by_id.get(object_id) is None:
+        if self.context[ScopeCtx].objects.get(object_id) is None:
             raise CompileError(f"Could not find object with ID '{object_id}'")
 
     @docs("name")
diff --git a/blueprintcompiler/language/gtk_size_group.py b/blueprintcompiler/language/gtk_size_group.py
index 80c47af..6a3ecb1 100644
--- a/blueprintcompiler/language/gtk_size_group.py
+++ b/blueprintcompiler/language/gtk_size_group.py
@@ -20,6 +20,7 @@
 
 from .gobject_object import ObjectContent, validate_parent_type
 from .common import *
+from .contexts import ScopeCtx
 
 
 class Widget(AstNode):
@@ -27,12 +28,15 @@ class Widget(AstNode):
 
     @validate("name")
     def obj_widget(self):
-        object = self.root.objects_by_id.get(self.tokens["name"])
+        object = self.context[ScopeCtx].objects.get(self.tokens["name"])
         type = self.root.gir.get_type("Widget", "Gtk")
         if object is None:
             raise CompileError(
                 f"Could not find object with ID {self.tokens['name']}",
-                did_you_mean=(self.tokens["name"], self.root.objects_by_id.keys()),
+                did_you_mean=(
+                    self.tokens["name"],
+                    self.context[ScopeCtx].objects.keys(),
+                ),
             )
         elif object.gir_class and not object.gir_class.assignable_to(type):
             raise CompileError(
diff --git a/blueprintcompiler/language/property_binding.py b/blueprintcompiler/language/property_binding.py
index ba8a29d..101bef5 100644
--- a/blueprintcompiler/language/property_binding.py
+++ b/blueprintcompiler/language/property_binding.py
@@ -18,7 +18,7 @@
 # SPDX-License-Identifier: LGPL-3.0-or-later
 
 from .common import *
-from .contexts import ValueTypeCtx
+from .contexts import ScopeCtx
 from .gobject_object import Object
 from .gtkbuilder_template import Template
 
@@ -71,7 +71,7 @@ class PropertyBinding(AstNode):
 
     @property
     def source_obj(self) -> T.Optional[Object]:
-        return self.root.objects_by_id.get(self.source)
+        return self.context[ScopeCtx].objects.get(self.source)
 
     @property
     def property_name(self) -> str:
@@ -98,7 +98,7 @@ class PropertyBinding(AstNode):
         if self.source_obj is None:
             raise CompileError(
                 f"Could not find object with ID {self.source}",
-                did_you_mean=(self.source, self.root.objects_by_id.keys()),
+                did_you_mean=(self.source, self.context[ScopeCtx].objects.keys()),
             )
 
     @validate("property")
diff --git a/blueprintcompiler/language/ui.py b/blueprintcompiler/language/ui.py
index 8d27c0e..ea2dac8 100644
--- a/blueprintcompiler/language/ui.py
+++ b/blueprintcompiler/language/ui.py
@@ -17,14 +17,13 @@
 #
 # SPDX-License-Identifier: LGPL-3.0-or-later
 
-from functools import cached_property
-
 from .. import gir
 from .imports import GtkDirective, Import
 from .gtkbuilder_template import Template
 from .gobject_object import Object
 from .gtk_menu import menu, Menu
 from .common import *
+from .contexts import ScopeCtx
 
 
 class UI(AstNode):
@@ -85,13 +84,9 @@ class UI(AstNode):
             or isinstance(child, Menu)
         ]
 
-    @cached_property
-    def objects_by_id(self):
-        return {
-            obj.tokens["id"]: obj
-            for obj in self.iterate_children_recursive()
-            if obj.tokens["id"] is not None
-        }
+    @context(ScopeCtx)
+    def scope_ctx(self) -> ScopeCtx:
+        return ScopeCtx(node=self)
 
     @validate()
     def gir_errors(self):
@@ -102,14 +97,4 @@ class UI(AstNode):
 
     @validate()
     def unique_ids(self):
-        passed = {}
-        for obj in self.iterate_children_recursive():
-            if obj.tokens["id"] is None:
-                continue
-
-            if obj.tokens["id"] in passed:
-                token = obj.group.tokens["id"]
-                raise CompileError(
-                    f"Duplicate object ID '{obj.tokens['id']}'", token.start, token.end
-                )
-            passed[obj.tokens["id"]] = obj
+        self.context[ScopeCtx].validate_unique_ids()
diff --git a/blueprintcompiler/language/values.py b/blueprintcompiler/language/values.py
index a1666cc..596823d 100644
--- a/blueprintcompiler/language/values.py
+++ b/blueprintcompiler/language/values.py
@@ -24,7 +24,7 @@ from .types import TypeName
 from .property_binding import PropertyBinding
 from .binding import Binding
 from .gobject_object import Object
-from .contexts import ValueTypeCtx
+from .contexts import ScopeCtx, ValueTypeCtx
 
 
 class TranslatedWithoutContext(AstNode):
@@ -274,7 +274,7 @@ class IdentLiteral(AstNode):
             return expected_type
         elif self.ident in ["true", "false"]:
             return gir.BoolType()
-        elif object := self.root.objects_by_id.get(self.ident):
+        elif object := self.context[ScopeCtx].objects.get(self.ident):
             return object.gir_class
         else:
             return None
@@ -294,11 +294,11 @@ class IdentLiteral(AstNode):
                 )
 
         elif expected_type is not None:
-            object = self.root.objects_by_id.get(self.ident)
+            object = self.context[ScopeCtx].objects.get(self.ident)
             if object is None:
                 raise CompileError(
                     f"Could not find object with ID {self.ident}",
-                    did_you_mean=(self.ident, self.root.objects_by_id.keys()),
+                    did_you_mean=(self.ident, self.context[ScopeCtx].objects.keys()),
                 )
             elif object.gir_class and not object.gir_class.assignable_to(expected_type):
                 raise CompileError(