diff --git a/src/Generator/PassBuilder.cs b/src/Generator/PassBuilder.cs
index 29b9d517..67a5d4aa 100644
--- a/src/Generator/PassBuilder.cs
+++ b/src/Generator/PassBuilder.cs
@@ -11,15 +11,18 @@ namespace Cxxi
     /// </summary>
     public class PassBuilder
     {
-        public List<TranslationUnitPass> Passes { get; set; }
+        public List<TranslationUnitPass> Passes { get; private set; }
+        public Library Library { get; private set; }
 
-        public PassBuilder()
+        public PassBuilder(Library library)
         {
             Passes = new List<TranslationUnitPass>();
+            Library = library;
         }
 
         public void AddPass(TranslationUnitPass pass)
         {
+            pass.Library = Library;
             Passes.Add(pass);
         }