diff --git a/build.sc b/build.sc
index 47076900..45b093ec 100644
--- a/build.sc
+++ b/build.sc
@@ -225,7 +225,7 @@ object docs extends BasePublishModule {
 
 object Deps {
   val smithy = new {
-    val smithyVersion = "1.63.0"
+    val smithyVersion = "1.66.0"
     val model = ivy"software.amazon.smithy:smithy-model:$smithyVersion"
     val awsTraits = ivy"software.amazon.smithy:smithy-aws-traits:$smithyVersion"
     val awsProtocolTestTraits =
diff --git a/modules/core/test/src/alloy/validation/SimpleRestJsonTimestampFormatValidatorSpec.scala b/modules/core/test/src/alloy/validation/SimpleRestJsonTimestampFormatValidatorSpec.scala
index 9d8e1375..2cb9025d 100644
--- a/modules/core/test/src/alloy/validation/SimpleRestJsonTimestampFormatValidatorSpec.scala
+++ b/modules/core/test/src/alloy/validation/SimpleRestJsonTimestampFormatValidatorSpec.scala
@@ -94,7 +94,7 @@ final class SimpleRestJsonTimestampFormatValidatorSpec extends munit.FunSuite {
         )
         .build()
     )
-    assertEquals(result, expected)
+    assertEquals(result.sortBy(_.toString), expected.sortBy(_.toString))
   }
 
   test(