diff --git a/tcmalloc/BUILD b/tcmalloc/BUILD
index 87a7fabdd..2af8229b0 100644
--- a/tcmalloc/BUILD
+++ b/tcmalloc/BUILD
@@ -108,6 +108,26 @@ cc_library(
     alwayslink = 1,
 )
 
+cc_library(
+    name = "tcmalloc_internal_methods_only",
+    srcs = [
+        "tcmalloc.cc",
+        "tcmalloc.h",
+    ],
+    copts = TCMALLOC_DEFAULT_COPTS + [
+        "-DTCMALLOC_INTERNAL_METHODS_ONLY",
+    ],
+    linkstatic = 1,
+    visibility = ["//tcmalloc:__subpackages__"],
+    deps = tcmalloc_deps + [
+        ":common_8k_pages",
+        "//tcmalloc/internal:allocation_guard",
+        "//tcmalloc/internal:overflow",
+        "//tcmalloc/internal:page_size",
+    ],
+    alwayslink = 1,
+)
+
 # Provides tcmalloc always; use per-thread mode.
 cc_library(
     name = "tcmalloc_deprecated_perthread",
diff --git a/tcmalloc/tcmalloc.cc b/tcmalloc/tcmalloc.cc
index 6cecd0217..c4f93ed0d 100644
--- a/tcmalloc/tcmalloc.cc
+++ b/tcmalloc/tcmalloc.cc
@@ -1094,7 +1094,12 @@ using tcmalloc::tcmalloc_internal::MallocAlignPolicy;
 using tcmalloc::tcmalloc_internal::MultiplyOverflow;
 
 // depends on TCMALLOC_HAVE_STRUCT_MALLINFO, so needs to come after that.
+#ifndef TCMALLOC_INTERNAL_METHODS_ONLY
 #include "tcmalloc/libc_override.h"
+#else
+#define TCMALLOC_ALIAS(tc_fn) \
+  __attribute__((alias(#tc_fn), visibility("default")))
+#endif  //  !TCMALLOC_INTERNAL_METHODS_ONLY
 
 extern "C" ABSL_CACHELINE_ALIGNED void* TCMallocInternalMalloc(
     size_t size) noexcept {
@@ -1110,6 +1115,7 @@ extern "C" ABSL_CACHELINE_ALIGNED void* TCMallocInternalNewNothrow(
   return fast_alloc(CppPolicy().Nothrow(), size);
 }
 
+#ifndef TCMALLOC_INTERNAL_METHODS_ONLY
 extern "C" ABSL_CACHELINE_ALIGNED ABSL_ATTRIBUTE_SECTION(google_malloc)
     tcmalloc::sized_ptr_t tcmalloc_size_returning_operator_new(size_t size) {
   return fast_alloc(CppPolicy().SizeReturning(), size);
@@ -1146,6 +1152,7 @@ extern "C" ABSL_CACHELINE_ALIGNED ABSL_ATTRIBUTE_SECTION(google_malloc)
                               .SizeReturning(),
                           size);
 }
+#endif  // !TCMALLOC_INTERNAL_METHODS_ONLY
 
 extern "C" ABSL_CACHELINE_ALIGNED void* TCMallocInternalMemalign(
     size_t align, size_t size) noexcept {
@@ -1540,6 +1547,7 @@ static TCMallocGuard module_enter_exit_hook;
 }  // namespace tcmalloc
 GOOGLE_MALLOC_SECTION_END
 
+#ifndef TCMALLOC_INTERNAL_METHODS_ONLY
 ABSL_CACHELINE_ALIGNED void* operator new(
     size_t size, tcmalloc::hot_cold_t hot_cold) noexcept(false) {
   if (hot_cold >= Parameters::min_hot_access_hint()) {
@@ -1623,3 +1631,4 @@ ABSL_CACHELINE_ALIGNED void* operator new[](
                       size);
   }
 }
+#endif  // !TCMALLOC_INTERNAL_METHODS_ONLY
diff --git a/tcmalloc/testing/BUILD b/tcmalloc/testing/BUILD
index cac898c3f..f5f5d1940 100644
--- a/tcmalloc/testing/BUILD
+++ b/tcmalloc/testing/BUILD
@@ -903,3 +903,18 @@ create_tcmalloc_testsuite(
         "@com_google_googletest//:gtest_main",
     ],
 )
+
+cc_test(
+    name = "parallel_test",
+    srcs = ["parallel_test.cc"],
+    copts = TCMALLOC_DEFAULT_COPTS,
+    malloc = "//tcmalloc/internal:system_malloc",
+    tags = ["nomsan"],
+    deps = [
+        "//tcmalloc:tcmalloc_internal_methods_only",  # buildcleaner: keep
+        "@com_google_absl//absl/base:config",
+        "@com_google_absl//absl/random",
+        "@com_google_absl//absl/time",
+        "@com_google_googletest//:gtest_main",
+    ],
+)
diff --git a/tcmalloc/testing/parallel_test.cc b/tcmalloc/testing/parallel_test.cc
new file mode 100644
index 000000000..d4e3a0a5c
--- /dev/null
+++ b/tcmalloc/testing/parallel_test.cc
@@ -0,0 +1,94 @@
+// Copyright 2023 The TCMalloc Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include <atomic>
+#include <cstddef>
+#include <thread>
+#include <vector>
+
+#include "gtest/gtest.h"
+#include "absl/base/config.h"
+#include "absl/random/random.h"
+#include "absl/time/clock.h"
+#include "absl/time/time.h"
+
+extern "C" {
+
+void* TCMallocInternalNew(size_t);
+void TCMallocInternalDelete(void*);
+void TCMallocInternalDeleteSized(void*, size_t);
+
+}  // extern "C"
+
+namespace tcmalloc {
+namespace {
+
+struct Allocator {
+  Allocator(std::atomic<bool>& stop, bool do_sized_delete)
+      : stop(stop), do_sized_delete(do_sized_delete) {}
+
+  void operator()() {
+    const int kNumAllocations = 65536;
+    std::vector<void*> v;
+    v.reserve(kNumAllocations);
+
+    absl::BitGen rng;
+
+    while (!stop.load(std::memory_order_acquire)) {
+      const size_t size = 1u << absl::LogUniform(rng, 1, 12);
+      for (int i = 0; i < kNumAllocations; ++i) {
+        v.push_back(TCMallocInternalNew(size));
+      }
+
+      for (void* ptr : v) {
+        if (do_sized_delete) {
+          TCMallocInternalDeleteSized(ptr, size);
+        } else {
+          TCMallocInternalDelete(ptr);
+        }
+      }
+      v.clear();
+    }
+  }
+
+  std::atomic<bool>& stop;
+  bool do_sized_delete;
+};
+
+TEST(ParallelTest, Stable) {
+#ifdef ABSL_HAVE_MEMORY_SANITIZER
+  // TODO(b/148986845):  Enable this.
+  GTEST_SKIP() << "Skipping under msan.";
+#endif
+#ifdef ABSL_HAVE_THREAD_SANITIZER
+  // TODO(b/274996721):  Enable this when Span::nonempty_index_ does not
+  // conflict with other bitfields.
+  GTEST_SKIP() << "Skipping under tsan.";
+#endif
+  std::atomic<bool> stop{false};
+  Allocator a1(stop, /*do_sized_delete=*/true),
+      a2(stop, /*do_sized_delete=*/true), a3(stop, /*do_sized_delete=*/false);
+
+  std::thread t1(a1), t2(a2), t3(a3);
+
+  absl::SleepFor(absl::Seconds(1));
+
+  stop.store(true, std::memory_order_release);
+  t1.join();
+  t2.join();
+  t3.join();
+}
+
+}  // namespace
+}  // namespace tcmalloc