diff --git a/AwsEncryptionSDK/dafny/AwsEncryptionSdk/src/AwsEncryptionSdkOperations.dfy b/AwsEncryptionSDK/dafny/AwsEncryptionSdk/src/AwsEncryptionSdkOperations.dfy
index 695b3379d..1a89973e7 100644
--- a/AwsEncryptionSDK/dafny/AwsEncryptionSdk/src/AwsEncryptionSdkOperations.dfy
+++ b/AwsEncryptionSDK/dafny/AwsEncryptionSdk/src/AwsEncryptionSdkOperations.dfy
@@ -17,7 +17,7 @@ include "Serialize/EncryptionContext.dfy"
 
 module AwsEncryptionSdkOperations refines AbstractAwsCryptographyEncryptionSdkOperations {
 
-  import Aws.Cryptography.Primitives
+  import Primitives = AtomicPrimitives
   import MPL = AwsCryptographyMaterialProvidersTypes
   import MaterialProviders
   import EncryptDecryptHelpers
diff --git a/AwsEncryptionSDK/dafny/AwsEncryptionSdk/src/EncryptDecrypt.dfy b/AwsEncryptionSDK/dafny/AwsEncryptionSdk/src/EncryptDecrypt.dfy
index 6a3762abe..5825b02cf 100644
--- a/AwsEncryptionSDK/dafny/AwsEncryptionSdk/src/EncryptDecrypt.dfy
+++ b/AwsEncryptionSDK/dafny/AwsEncryptionSdk/src/EncryptDecrypt.dfy
@@ -15,7 +15,7 @@ module EncryptDecryptHelpers {
   import Types = AwsCryptographyEncryptionSdkTypes
   import MPL = AwsCryptographyMaterialProvidersTypes
   import MaterialProviders
-  import Aws.Cryptography.Primitives
+  import Primitives = AtomicPrimitives
   import MessageBody
   import SerializableTypes
   import opened SerializeFunctions
diff --git a/AwsEncryptionSDK/dafny/AwsEncryptionSdk/src/Index.dfy b/AwsEncryptionSDK/dafny/AwsEncryptionSdk/src/Index.dfy
index cf46c3714..ab851b1a8 100644
--- a/AwsEncryptionSDK/dafny/AwsEncryptionSdk/src/Index.dfy
+++ b/AwsEncryptionSDK/dafny/AwsEncryptionSdk/src/Index.dfy
@@ -7,7 +7,7 @@ module
   {:extern "software.amazon.cryptography.encryptionsdk.internaldafny" }
   EncryptionSdk refines AbstractAwsCryptographyEncryptionSdkService {
   import Operations = AwsEncryptionSdkOperations
-  import Aws.Cryptography.Primitives
+  import Primitives = AtomicPrimitives
   import MaterialProviders
   import AwsCryptographyMaterialProvidersTypes
 
diff --git a/AwsEncryptionSDK/dafny/AwsEncryptionSdk/src/KeyDerivation.dfy b/AwsEncryptionSDK/dafny/AwsEncryptionSdk/src/KeyDerivation.dfy
index 2607f528c..2456f756e 100644
--- a/AwsEncryptionSDK/dafny/AwsEncryptionSdk/src/KeyDerivation.dfy
+++ b/AwsEncryptionSDK/dafny/AwsEncryptionSdk/src/KeyDerivation.dfy
@@ -12,7 +12,7 @@ module KeyDerivation {
   import Types = AwsCryptographyEncryptionSdkTypes
   import MPL = AwsCryptographyMaterialProvidersTypes
   import AwsCryptographyPrimitivesTypes
-  import Aws.Cryptography.Primitives
+  import Primitives = AtomicPrimitives
   import HeaderTypes
   import SerializableTypes
 
diff --git a/AwsEncryptionSDK/dafny/AwsEncryptionSdk/src/MessageBody.dfy b/AwsEncryptionSDK/dafny/AwsEncryptionSdk/src/MessageBody.dfy
index 68315907a..0c0199111 100644
--- a/AwsEncryptionSDK/dafny/AwsEncryptionSdk/src/MessageBody.dfy
+++ b/AwsEncryptionSDK/dafny/AwsEncryptionSdk/src/MessageBody.dfy
@@ -22,7 +22,7 @@ module MessageBody {
   import opened UInt = StandardLibrary.UInt
   import Types = AwsCryptographyEncryptionSdkTypes
   import MPL = AwsCryptographyMaterialProvidersTypes
-  import Aws.Cryptography.Primitives
+  import Primitives = AtomicPrimitives
   import Streams
   import UTF8
   import SerializableTypes
diff --git a/AwsEncryptionSDK/dafny/AwsEncryptionSdk/test/Fixtures.dfy b/AwsEncryptionSDK/dafny/AwsEncryptionSdk/test/Fixtures.dfy
index b7edf42a6..a7d7d5652 100644
--- a/AwsEncryptionSDK/dafny/AwsEncryptionSdk/test/Fixtures.dfy
+++ b/AwsEncryptionSDK/dafny/AwsEncryptionSdk/test/Fixtures.dfy
@@ -9,7 +9,7 @@ module Fixtures {
   import primitivesTypes = AwsCryptographyPrimitivesTypes
   import mplTypes = AwsCryptographyMaterialProvidersTypes
   import opened UInt = StandardLibrary.UInt
-  import Aws.Cryptography.Primitives
+  import Primitives = AtomicPrimitives
   
   // The following are test resources that exist in tests accounts:
 
diff --git a/mpl b/mpl
index ea0fe508d..4f7e715d2 160000
--- a/mpl
+++ b/mpl
@@ -1 +1 @@
-Subproject commit ea0fe508dca214b9c9bdaf0fc21122e83971ef1b
+Subproject commit 4f7e715d29459b0e637067066c0fec321e00cd9b