diff --git a/AwsCryptographicMaterialProviders/runtimes/rust/src/dafny_libraries.rs b/AwsCryptographicMaterialProviders/runtimes/rust/src/dafny_libraries.rs
index de16d5af7..a5e7f437f 100644
--- a/AwsCryptographicMaterialProviders/runtimes/rust/src/dafny_libraries.rs
+++ b/AwsCryptographicMaterialProviders/runtimes/rust/src/dafny_libraries.rs
@@ -71,6 +71,12 @@ pub mod DafnyLibraries {
         }
     }
 
+    impl<K: ::dafny_runtime::DafnyTypeEq, V: ::dafny_runtime::DafnyTypeEq>
+        ::dafny_runtime::UpcastObject<dyn ::std::any::Any> for MutableMap<K, V>
+    {
+        ::dafny_runtime::UpcastObjectFn!(dyn ::std::any::Any);
+    }
+
     pub mod FileIO {
         use std::fs::File;
         use std::io::Read;
@@ -89,7 +95,12 @@ pub mod DafnyLibraries {
 
             let mut file = match File::open(path) {
                 Err(why) => {
-                    let err_msg = format!("couldn't open {} for reading from {}: {}", path.display(), curr_dir(), why);
+                    let err_msg = format!(
+                        "couldn't open {} for reading from {}: {}",
+                        path.display(),
+                        curr_dir(),
+                        why
+                    );
                     let err_msg = dafny_runtime::dafny_runtime_conversions::unicode_chars_false::string_to_dafny_string(&err_msg);
                     return (true, dafny_runtime::Sequence::default(), err_msg);
                 }
@@ -111,8 +122,7 @@ pub mod DafnyLibraries {
             }
         }
 
-        fn curr_dir() -> String
-        {
+        fn curr_dir() -> String {
             let path = std::env::current_dir();
             match path {
                 Ok(path) => format!("{}", path.display()),
@@ -137,7 +147,12 @@ pub mod DafnyLibraries {
                 .open(path);
             let mut file = match maybe_file {
                 Err(why) => {
-                    let err_msg = format!("couldn't open {} for writing from {}: {}", path.display(), curr_dir(), why);
+                    let err_msg = format!(
+                        "couldn't open {} for writing from {}: {}",
+                        path.display(),
+                        curr_dir(),
+                        why
+                    );
                     let err_msg = dafny_runtime::dafny_runtime_conversions::unicode_chars_false::string_to_dafny_string(&err_msg);
                     return (true, err_msg);
                 }
diff --git a/StandardLibrary/runtimes/java/src/main/java/DafnyLibraries/MutableMap.java b/StandardLibrary/runtimes/java/src/main/java/DafnyLibraries/MutableMap.java
index b9f2f1316..76f0ba5d9 100644
--- a/StandardLibrary/runtimes/java/src/main/java/DafnyLibraries/MutableMap.java
+++ b/StandardLibrary/runtimes/java/src/main/java/DafnyLibraries/MutableMap.java
@@ -8,8 +8,7 @@
 import java.util.Map;
 import java.util.concurrent.*;
 
-public class MutableMap<K, V>
-  extends DafnyLibraries._ExternBase_MutableMap<K, V> {
+public class MutableMap<K, V> implements DafnyLibraries.MutableMapTrait<K, V> {
 
   private ConcurrentHashMap<K, V> m;
 
@@ -17,7 +16,6 @@ public MutableMap(
     dafny.TypeDescriptor<K> _td_K,
     dafny.TypeDescriptor<V> _td_V
   ) {
-    super(_td_K, _td_V);
     m = new ConcurrentHashMap<K, V>();
   }
 
diff --git a/StandardLibrary/runtimes/python/src/smithy_dafny_standard_library/internaldafny/extern/DafnyLibraries.py b/StandardLibrary/runtimes/python/src/smithy_dafny_standard_library/internaldafny/extern/DafnyLibraries.py
index 4c2c4f2e5..3edd73b2f 100644
--- a/StandardLibrary/runtimes/python/src/smithy_dafny_standard_library/internaldafny/extern/DafnyLibraries.py
+++ b/StandardLibrary/runtimes/python/src/smithy_dafny_standard_library/internaldafny/extern/DafnyLibraries.py
@@ -23,7 +23,7 @@ def Unlock(self):
         self.lock.release()
 
 
-class MutableMap(smithy_dafny_standard_library.internaldafny.generated.DafnyLibraries.MutableMap):
+class MutableMap(smithy_dafny_standard_library.internaldafny.generated.DafnyLibraries.MutableMapTrait):
     def ctor__(self):
         pass
         
diff --git a/libraries b/libraries
index fabf44d71..7af1ae1b9 160000
--- a/libraries
+++ b/libraries
@@ -1 +1 @@
-Subproject commit fabf44d71c6d5065b0021cb4e5e96b5128c87d39
+Subproject commit 7af1ae1b99aa893616db42c0ddeb5af6827b1524