diff --git a/src/core/BUILD b/src/core/BUILD
index 6b90243d253..68efe9d4737 100644
--- a/src/core/BUILD
+++ b/src/core/BUILD
@@ -1124,6 +1124,10 @@ grpc_cc_library(
     hdrs = [
         "lib/resource_quota/arena.h",
     ],
+    external_deps = [
+        "absl/meta:type_traits",
+        "absl/utility",
+    ],
     visibility = [
         "@grpc:alt_grpc_base_legacy",
     ],
diff --git a/src/core/lib/resource_quota/arena.cc b/src/core/lib/resource_quota/arena.cc
index 332bdc4c85c..d37ef426490 100644
--- a/src/core/lib/resource_quota/arena.cc
+++ b/src/core/lib/resource_quota/arena.cc
@@ -121,7 +121,6 @@ void Arena::ManagedNewObject::Link(std::atomic<ManagedNewObject*>* head) {
   }
 }
 
-#ifndef GRPC_ARENA_POOLED_ALLOCATIONS_USE_MALLOC
 void* Arena::AllocPooled(size_t obj_size, size_t alloc_size,
                          std::atomic<FreePoolNode*>* head) {
   // ABA mitigation:
@@ -178,6 +177,5 @@ void Arena::FreePooled(void* p, std::atomic<FreePoolNode*>* head) {
       node->next, node, std::memory_order_acq_rel, std::memory_order_relaxed)) {
   }
 }
-#endif
 
 }  // namespace grpc_core
diff --git a/src/core/lib/resource_quota/arena.h b/src/core/lib/resource_quota/arena.h
index 9a072458ea0..1dcb530243e 100644
--- a/src/core/lib/resource_quota/arena.h
+++ b/src/core/lib/resource_quota/arena.h
@@ -30,10 +30,14 @@
 #include <stddef.h>
 
 #include <atomic>
-#include <iosfwd>
+#include <limits>
 #include <memory>
+#include <new>
 #include <utility>
 
+#include "absl/meta/type_traits.h"
+#include "absl/utility/utility.h"
+
 #include <grpc/event_engine/memory_allocator.h>
 
 #include "src/core/lib/gpr/alloc.h"
@@ -41,14 +45,13 @@
 #include "src/core/lib/promise/context.h"
 #include "src/core/lib/resource_quota/memory_quota.h"
 
-#define GRPC_ARENA_POOLED_ALLOCATIONS_USE_MALLOC
+// #define GRPC_ARENA_POOLED_ALLOCATIONS_USE_MALLOC
 // #define GRPC_ARENA_TRACE_POOLED_ALLOCATIONS
 
 namespace grpc_core {
 
 namespace arena_detail {
 
-#ifndef GRPC_ARENA_POOLED_ALLOCATIONS_USE_MALLOC
 struct PoolAndSize {
   size_t alloc_size;
   size_t pool_index;
@@ -110,19 +113,16 @@ PoolAndSize ChoosePoolForAllocationSize(
     size_t n, absl::integer_sequence<size_t, kBucketSizes...>) {
   return ChoosePoolForAllocationSizeImpl<0, kBucketSizes...>::Fn(n);
 }
-#endif
 
 }  // namespace arena_detail
 
 class Arena {
-#ifndef GRPC_ARENA_POOLED_ALLOCATIONS_USE_MALLOC
   // Selected pool sizes.
   // How to tune: see tools/codegen/core/optimize_arena_pool_sizes.py
   using PoolSizes = absl::integer_sequence<size_t, 80, 304, 528, 1024>;
   struct FreePoolNode {
     FreePoolNode* next;
   };
-#endif
 
  public:
   // Create an arena, with \a initial_size bytes in the first allocated buffer.
@@ -372,11 +372,9 @@ class Arena {
 
   void* AllocZone(size_t size);
 
-#ifndef GRPC_ARENA_POOLED_ALLOCATIONS_USE_MALLOC
   void* AllocPooled(size_t obj_size, size_t alloc_size,
                     std::atomic<FreePoolNode*>* head);
   static void FreePooled(void* p, std::atomic<FreePoolNode*>* head);
-#endif
 
   void TracePoolAlloc(size_t size, void* ptr) {
     (void)size;
diff --git a/src/core/lib/security/transport/client_auth_filter.cc b/src/core/lib/security/transport/client_auth_filter.cc
index 57d10f9a0b7..8094ff429a5 100644
--- a/src/core/lib/security/transport/client_auth_filter.cc
+++ b/src/core/lib/security/transport/client_auth_filter.cc
@@ -196,13 +196,10 @@ ArenaPromise<ServerMetadataHandle> ClientAuthFilter::MakeCallPromise(
   if (host == nullptr) {
     return next_promise_factory(std::move(call_args));
   }
-  return TrySeq(
-      args_.security_connector->CheckCallHost(host->as_string_view(),
-                                              args_.auth_context.get()),
-      [this, call_args = std::move(call_args)]() mutable {
-        return GetCallCredsMetadata(std::move(call_args));
-      },
-      next_promise_factory);
+  return TrySeq(args_.security_connector->CheckCallHost(
+                    host->as_string_view(), args_.auth_context.get()),
+                GetCallCredsMetadata(std::move(call_args)),
+                next_promise_factory);
 }
 
 absl::StatusOr<ClientAuthFilter> ClientAuthFilter::Create(
diff --git a/test/core/resource_quota/arena_test.cc b/test/core/resource_quota/arena_test.cc
index 1e35a105f6b..665364305f3 100644
--- a/test/core/resource_quota/arena_test.cc
+++ b/test/core/resource_quota/arena_test.cc
@@ -191,7 +191,6 @@ bool IsScribbled(Int* ints, int n, int offset) {
   return true;
 }
 
-#ifndef GRPC_ARENA_POOLED_ALLOCATIONS_USE_MALLOC
 TEST_F(ArenaTest, PooledObjectsArePooled) {
   struct TestObj {
     char a[100];
@@ -209,7 +208,6 @@ TEST_F(ArenaTest, PooledObjectsArePooled) {
   Scribble(obj->a, 100, 2);
   EXPECT_TRUE(IsScribbled(obj->a, 100, 2));
 }
-#endif
 
 TEST_F(ArenaTest, CreateManyObjects) {
   struct TestObj {
@@ -240,11 +238,7 @@ TEST_F(ArenaTest, CreateManyObjectsWithDestructors) {
 TEST_F(ArenaTest, CreatePoolArray) {
   auto arena = MakeScopedArena(1024, &memory_allocator_);
   auto p = arena->MakePooledArray<int>(1024);
-#ifndef GRPC_ARENA_POOLED_ALLOCATIONS_USE_MALLOC
   EXPECT_FALSE(p.get_deleter().has_freelist());
-#else
-  EXPECT_TRUE(p.get_deleter().has_freelist());
-#endif
   p = arena->MakePooledArray<int>(5);
   EXPECT_TRUE(p.get_deleter().has_freelist());
   Scribble(p.get(), 5, 1);