diff --git a/test/wasm-api-tests/wasm-api-test.h b/test/wasm-api-tests/wasm-api-test.h
index d04a731429..f566d398ca 100644
--- a/test/wasm-api-tests/wasm-api-test.h
+++ b/test/wasm-api-tests/wasm-api-test.h
@@ -41,9 +41,10 @@ class WasmCapiTest : public ::testing::Test {
   WasmCapiTest()
       : Test(),
         engine_(Engine::make()),
-        zone_(&allocator_, ZONE_NAME),
-        wire_bytes_(&zone_),
-        builder_(&zone_),
+        allocator_(std::make_unique<AccountingAllocator>()),
+        zone_(std::make_unique<Zone>(allocator_.get(), ZONE_NAME)),
+        wire_bytes_(zone_.get()),
+        builder_(zone_->New<WasmModuleBuilder>(zone_.get())),
         exports_(ownvec<Extern>::make()),
         wasm_i_i_sig_(1, 1, wasm_i_i_sig_types_) {
     store_ = Store::make(engine_.get());
@@ -53,7 +54,7 @@ class WasmCapiTest : public ::testing::Test {
   }
 
   void Compile() {
-    builder_.WriteTo(&wire_bytes_);
+    builder_->WriteTo(&wire_bytes_);
     size_t size = wire_bytes_.end() - wire_bytes_.begin();
     vec<byte_t> binary = vec<byte_t>::make(
         size,
@@ -119,10 +120,13 @@ class WasmCapiTest : public ::testing::Test {
     instance_.reset();
     module_.reset();
     store_.reset();
+    builder_ = nullptr;
+    zone_.reset();
+    allocator_.reset();
     engine_.reset();
   }
 
-  WasmModuleBuilder* builder() { return &builder_; }
+  WasmModuleBuilder* builder() { return builder_; }
   Engine* engine() { return engine_.get(); }
   Store* store() { return store_.get(); }
   Module* module() { return module_.get(); }
@@ -135,10 +139,10 @@ class WasmCapiTest : public ::testing::Test {
 
  private:
   own<Engine> engine_;
-  AccountingAllocator allocator_;
-  Zone zone_;
+  own<AccountingAllocator> allocator_;
+  own<Zone> zone_;
   ZoneBuffer wire_bytes_;
-  WasmModuleBuilder builder_;
+  WasmModuleBuilder* builder_;
   own<Store> store_;
   own<Module> module_;
   own<Instance> instance_;