diff --git a/blueprintcompiler/gir.py b/blueprintcompiler/gir.py
index e85190b..b289b5e 100644
--- a/blueprintcompiler/gir.py
+++ b/blueprintcompiler/gir.py
@@ -638,29 +638,35 @@ class Namespace(GirNode):
     def __init__(self, repo: "Repository", tl: typelib.Typelib) -> None:
         super().__init__(repo, tl)
 
-        self.entries: T.Dict[str, GirType] = {}
+    @cached_property
+    def entries(self) -> T.Mapping[str, GirType]:
+        entries: dict[str, GirType] = {}
+
+        n_local_entries: int = self.tl.HEADER_N_ENTRIES
+        directory: typelib.Typelib = self.tl.HEADER_DIRECTORY
+        blob_size: int = self.tl.header.HEADER_ENTRY_BLOB_SIZE
 
-        n_local_entries: int = tl.HEADER_N_ENTRIES
-        directory: typelib.Typelib = tl.HEADER_DIRECTORY
         for i in range(n_local_entries):
-            entry = directory[i * tl.HEADER_ENTRY_BLOB_SIZE]
+            entry = directory[i * blob_size]
             entry_name: str = entry.DIR_ENTRY_NAME
             entry_type: int = entry.DIR_ENTRY_BLOB_TYPE
             entry_blob: typelib.Typelib = entry.DIR_ENTRY_OFFSET
 
             if entry_type == typelib.BLOB_TYPE_ENUM:
-                self.entries[entry_name] = Enumeration(self, entry_blob)
+                entries[entry_name] = Enumeration(self, entry_blob)
             elif entry_type == typelib.BLOB_TYPE_FLAGS:
-                self.entries[entry_name] = Bitfield(self, entry_blob)
+                entries[entry_name] = Bitfield(self, entry_blob)
             elif entry_type == typelib.BLOB_TYPE_OBJECT:
-                self.entries[entry_name] = Class(self, entry_blob)
+                entries[entry_name] = Class(self, entry_blob)
             elif entry_type == typelib.BLOB_TYPE_INTERFACE:
-                self.entries[entry_name] = Interface(self, entry_blob)
+                entries[entry_name] = Interface(self, entry_blob)
             elif (
                 entry_type == typelib.BLOB_TYPE_BOXED
                 or entry_type == typelib.BLOB_TYPE_STRUCT
             ):
-                self.entries[entry_name] = Boxed(self, entry_blob)
+                entries[entry_name] = Boxed(self, entry_blob)
+
+        return entries
 
     @cached_property
     def xml(self):
diff --git a/blueprintcompiler/language/ui.py b/blueprintcompiler/language/ui.py
index 033e2ca..533d21b 100644
--- a/blueprintcompiler/language/ui.py
+++ b/blueprintcompiler/language/ui.py
@@ -17,6 +17,8 @@
 #
 # 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
@@ -42,7 +44,7 @@ class UI(AstNode):
         ),
     ]
 
-    @property
+    @cached_property
     def gir(self) -> gir.GirContext:
         gir_ctx = gir.GirContext()
         self._gir_errors = []
diff --git a/blueprintcompiler/typelib.py b/blueprintcompiler/typelib.py
index 6babc10..54ee341 100644
--- a/blueprintcompiler/typelib.py
+++ b/blueprintcompiler/typelib.py
@@ -237,9 +237,7 @@ class Typelib:
         if loc == 0:
             return None
 
-        end = loc
-        while self._typelib_file[end] != 0:
-            end += 1
+        end = self._typelib_file.find(b"\0", loc)
         return self._typelib_file[loc:end].decode("utf-8")
 
     def _int(self, size, signed) -> int: