diff --git a/rust/test/cpp/BUILD b/rust/test/cpp/BUILD
index 91782bf48b..86976b077c 100644
--- a/rust/test/cpp/BUILD
+++ b/rust/test/cpp/BUILD
@@ -9,3 +9,19 @@
 # To do that use:
 # * `rust_cc_proto_library` instead of `rust_proto_library`.
 # * `//rust:protobuf_cpp` instead of `//rust:protobuf``.
+
+load("@rules_rust//rust:defs.bzl", "rust_test")
+
+rust_test(
+    name = "accessors_test",
+    srcs = ["accessors_test.rs"],
+    tags = [
+        # TODO(b/270274576): Enable testing on arm once we have a Rust Arm toolchain.
+        "not_build:arm",
+        # TODO(b/243126140): Enable tsan once we support sanitizers with Rust.
+        "notsan",
+        # TODO(b/243126140): Enable msan once we support sanitizers with Rust.
+        "nomsan",
+    ],
+    deps = ["//rust/test:unittest_cc_rust_proto"],
+)
diff --git a/rust/test/cpp/accessors_test.rs b/rust/test/cpp/accessors_test.rs
new file mode 100644
index 0000000000..c43f49a410
--- /dev/null
+++ b/rust/test/cpp/accessors_test.rs
@@ -0,0 +1,55 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2023 Google Inc.  All rights reserved.
+// https://developers.google.com/protocol-buffers/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+/// Tests covering accessors for singular bool and int64 fields.
+
+#[test]
+fn test_optional_int64_accessors() {
+    let mut msg = unittest_proto::TestAllTypes::new();
+    assert_eq!(msg.optional_int64(), None);
+
+    msg.optional_int64_set(Some(42));
+    assert_eq!(msg.optional_int64(), Some(42));
+
+    msg.optional_int64_set(None);
+    assert_eq!(msg.optional_int64(), None);
+}
+
+#[test]
+fn test_optional_bool_accessors() {
+    let mut msg = unittest_proto::TestAllTypes::new();
+    assert_eq!(msg.optional_bool(), None);
+
+    msg.optional_bool_set(Some(true));
+    assert_eq!(msg.optional_bool(), Some(true));
+
+    msg.optional_bool_set(None);
+    assert_eq!(msg.optional_bool(), None);
+}
diff --git a/rust/test/cpp/interop/main.rs b/rust/test/cpp/interop/main.rs
index 618f98ebce..92174ff5b3 100644
--- a/rust/test/cpp/interop/main.rs
+++ b/rust/test/cpp/interop/main.rs
@@ -48,6 +48,13 @@ fn mutate_message_in_cpp() {
     assert_serializes_equally!(msg);
 }
 
+#[test]
+fn mutate_message_in_rust() {
+    let mut msg = unittest_proto::TestAllTypes::new();
+    msg.optional_int64_set(Some(43));
+    assert_serializes_equally!(msg);
+}
+
 #[test]
 fn deserialize_message_in_rust() {
     let serialized = unsafe { SerializeMutatedInstance() };
diff --git a/src/google/protobuf/compiler/rust/generator.cc b/src/google/protobuf/compiler/rust/generator.cc
index fc100a5b81..e5bc5e072d 100644
--- a/src/google/protobuf/compiler/rust/generator.cc
+++ b/src/google/protobuf/compiler/rust/generator.cc
@@ -30,6 +30,7 @@
 
 #include "google/protobuf/compiler/rust/generator.h"
 
+#include <optional>
 #include <string>
 #include <utility>
 #include <vector>
@@ -38,7 +39,9 @@
 #include "absl/strings/str_cat.h"
 #include "absl/strings/str_replace.h"
 #include "absl/strings/string_view.h"
+#include "absl/strings/substitute.h"
 #include "absl/types/optional.h"
+#include "google/protobuf/compiler/cpp/helpers.h"
 #include "google/protobuf/compiler/cpp/names.h"
 #include "google/protobuf/compiler/rust/upb_kernel.h"
 #include "google/protobuf/descriptor.h"
@@ -107,15 +110,166 @@ std::string GetUnderscoreDelimitedFullName(const Descriptor* msg) {
   return result;
 }
 
+std::string GetAccessorThunkName(
+    const FieldDescriptor* field, absl::string_view op,
+    absl::string_view underscore_delimited_full_name) {
+  return absl::Substitute("__rust_proto_thunk__$0_$1_$2",
+                          underscore_delimited_full_name, op, field->name());
+}
+
+bool IsSupportedFieldType(const FieldDescriptor* field) {
+  return !field->is_repeated() &&
+         (field->cpp_type() == FieldDescriptor::CPPTYPE_BOOL ||
+          field->cpp_type() == FieldDescriptor::CPPTYPE_INT64);
+}
+
+std::string PrimitiveRsTypeName(const FieldDescriptor* field) {
+  switch (field->cpp_type()) {
+    case FieldDescriptor::CPPTYPE_INT64:
+      return "i64";
+    case FieldDescriptor::CPPTYPE_BOOL:
+      return "bool";
+    default:
+      break;
+  }
+  ABSL_LOG(FATAL) << "Unsupported field type: " << field->type_name();
+  return "";
+}
+
+void GenerateAccessorFns(const Descriptor* msg, google::protobuf::io::Printer& p,
+                         absl::string_view underscore_delimited_full_name) {
+  for (int i = 0; i < msg->field_count(); ++i) {
+    const FieldDescriptor* field = msg->field(i);
+    if (!IsSupportedFieldType(field)) {
+      continue;
+    }
+    p.Emit(
+        {
+            {"field_name", field->name()},
+            {"FieldType", PrimitiveRsTypeName(field)},
+            {"hazzer_thunk_name",
+             GetAccessorThunkName(field, "has",
+                                  underscore_delimited_full_name)},
+            {"getter_thunk_name",
+             GetAccessorThunkName(field, "", underscore_delimited_full_name)},
+            {"setter_thunk_name",
+             GetAccessorThunkName(field, "set",
+                                  underscore_delimited_full_name)},
+            {"clearer_thunk_name",
+             GetAccessorThunkName(field, "clear",
+                                  underscore_delimited_full_name)},
+        },
+        R"rs(
+             pub fn $field_name$(&self) -> Option<$FieldType$> {
+               if !unsafe { $hazzer_thunk_name$(self.msg) } {
+                return None;
+               }
+               Some(unsafe { $getter_thunk_name$(self.msg) })
+             }
+             pub fn $field_name$_set(&mut self, val: Option<$FieldType$>) {
+               match val {
+                 Some(val) => unsafe { $setter_thunk_name$(self.msg, val) },
+                 None => unsafe { $clearer_thunk_name$(self.msg) },
+               }
+             }
+           )rs");
+  }
+}
+
+void GenerateAccessorThunkRsDeclarations(
+    const Descriptor* msg, google::protobuf::io::Printer& p,
+    std::string underscore_delimited_full_name) {
+  for (int i = 0; i < msg->field_count(); ++i) {
+    const FieldDescriptor* field = msg->field(i);
+    if (!IsSupportedFieldType(field)) {
+      continue;
+    }
+    p.Emit(
+        {
+            {"FieldType", PrimitiveRsTypeName(field)},
+            {"hazzer_thunk_name",
+             GetAccessorThunkName(field, "has",
+                                  underscore_delimited_full_name)},
+            {"getter_thunk_name",
+             GetAccessorThunkName(field, "", underscore_delimited_full_name)},
+            {"setter_thunk_name",
+             GetAccessorThunkName(field, "set",
+                                  underscore_delimited_full_name)},
+            {"clearer_thunk_name",
+             GetAccessorThunkName(field, "clear",
+                                  underscore_delimited_full_name)},
+        },
+        R"rs(
+            fn $hazzer_thunk_name$(raw_msg: ::__std::ptr::NonNull<u8>) -> bool;
+            fn $getter_thunk_name$(raw_msg: ::__std::ptr::NonNull<u8>) -> $FieldType$;
+            fn $setter_thunk_name$(raw_msg: ::__std::ptr::NonNull<u8>, val: $FieldType$);
+            fn $clearer_thunk_name$(raw_msg: ::__std::ptr::NonNull<u8>);
+           )rs");
+  }
+}
+
+void GenerateAccessorThunksCcDefinitions(
+    const Descriptor* msg, google::protobuf::io::Printer& p,
+    absl::string_view underscore_delimited_full_name) {
+  for (int i = 0; i < msg->field_count(); ++i) {
+    const FieldDescriptor* field = msg->field(i);
+    if (!IsSupportedFieldType(field)) {
+      continue;
+    }
+    p.Emit(
+        {{"field_name", field->name()},
+         {"FieldType", cpp::PrimitiveTypeName(field->cpp_type())},
+         {"namespace", cpp::Namespace(msg)},
+         {"hazzer_thunk_name",
+          GetAccessorThunkName(field, "has", underscore_delimited_full_name)},
+         {"getter_thunk_name",
+          GetAccessorThunkName(field, "", underscore_delimited_full_name)},
+         {"setter_thunk_name",
+          GetAccessorThunkName(field, "set", underscore_delimited_full_name)},
+         {"clearer_thunk_name",
+          GetAccessorThunkName(field, "clear",
+                               underscore_delimited_full_name)}},
+        R"cc(
+          extern "C" {
+          bool $hazzer_thunk_name$($namespace$::$Msg$* msg) {
+            return msg->has_$field_name$();
+          }
+          $FieldType$ $getter_thunk_name$($namespace$::$Msg$* msg) {
+            return msg->$field_name$();
+          }
+          void $setter_thunk_name$($namespace$::$Msg$* msg, $FieldType$ val) {
+            msg->set_$field_name$(val);
+          }
+          void $clearer_thunk_name$($namespace$::$Msg$* msg) {
+            msg->clear_$field_name$();
+          }
+          }
+        )cc");
+  }
+}
+
 void GenerateForCpp(const FileDescriptor* file, google::protobuf::io::Printer& p) {
   for (int i = 0; i < file->message_type_count(); ++i) {
     const Descriptor* msg = file->message_type(i);
+    std::string underscore_delimited_full_name =
+        GetUnderscoreDelimitedFullName(msg);
     p.Emit(
         {
             {"Msg", msg->name()},
-            {"pkg_Msg", GetUnderscoreDelimitedFullName(msg)},
+            {"pkg_Msg", underscore_delimited_full_name},
+            {"accessor_fns",
+             [&] {
+               GenerateAccessorFns(file->message_type(i), p,
+                                   underscore_delimited_full_name);
+             }},
+            {"accessor_thunks",
+             [&] {
+               GenerateAccessorThunkRsDeclarations(
+                   file->message_type(i), p, underscore_delimited_full_name);
+             }},
         },
         R"rs(
+          #[allow(non_camel_case_types)]
           pub struct $Msg$ {
             msg: ::__std::ptr::NonNull<u8>,
           }
@@ -141,12 +295,15 @@ void GenerateForCpp(const FileDescriptor* file, google::protobuf::io::Printer& p
               };
               success.then_some(()).ok_or(::__pb::ParseError)
             }
+            $accessor_fns$
           }
 
           extern "C" {
             fn __rust_proto_thunk__$pkg_Msg$__new() -> ::__std::ptr::NonNull<u8>;
             fn __rust_proto_thunk__$pkg_Msg$__serialize(raw_msg: ::__std::ptr::NonNull<u8>) -> ::__pb::SerializedData;
             fn __rust_proto_thunk__$pkg_Msg$__deserialize(raw_msg: ::__std::ptr::NonNull<u8>, data: ::__pb::SerializedData) -> bool;
+
+            $accessor_thunks$
           }
         )rs");
   }
@@ -155,11 +312,18 @@ void GenerateForCpp(const FileDescriptor* file, google::protobuf::io::Printer& p
 void GenerateThunksForCpp(const FileDescriptor* file, google::protobuf::io::Printer& p) {
   for (int i = 0; i < file->message_type_count(); ++i) {
     const Descriptor* msg = file->message_type(i);
+    std::string underscore_delimited_full_name =
+        GetUnderscoreDelimitedFullName(msg);
     p.Emit(
         {
             {"Msg", msg->name()},
             {"pkg_Msg", GetUnderscoreDelimitedFullName(msg)},
             {"namespace", cpp::Namespace(msg)},
+            {"accessor_thunks",
+             [&] {
+               GenerateAccessorThunksCcDefinitions(
+                   file->message_type(i), p, underscore_delimited_full_name);
+             }},
         },
         R"cc(
           extern "C" {
@@ -175,6 +339,8 @@ void GenerateThunksForCpp(const FileDescriptor* file, google::protobuf::io::Prin
               google::protobuf::rust_internal::SerializedData data) {
             return msg->ParseFromArray(data.data, data.len);
           }
+
+          $accessor_thunks$
           }
         )cc");
   }
diff --git a/src/google/protobuf/compiler/rust/upb_kernel.cc b/src/google/protobuf/compiler/rust/upb_kernel.cc
index 18fb0efdbd..69104b9f68 100644
--- a/src/google/protobuf/compiler/rust/upb_kernel.cc
+++ b/src/google/protobuf/compiler/rust/upb_kernel.cc
@@ -30,6 +30,7 @@
 
 #include "google/protobuf/compiler/rust/upb_kernel.h"
 
+#include <optional>
 #include <string>
 #include <utility>
 #include <vector>