diff --git a/testing/fuzzers/BUILD.gn b/testing/fuzzers/BUILD.gn
index b97c08f..0fe1021 100644
--- a/testing/fuzzers/BUILD.gn
+++ b/testing/fuzzers/BUILD.gn
@@ -90,7 +90,10 @@
   testonly = true
   sources = [ "pdf_fuzzer_init_public.cc" ]
   include_dirs = [ "../.." ]
-  deps = [ "../../:pdfium_public_headers" ]
+  deps = [
+    ":fuzzer_utils",
+    "../../:pdfium_public_headers",
+  ]
   if (pdf_enable_v8) {
     configs += [ "//v8:external_startup_data" ]
     deps += [
@@ -98,6 +101,9 @@
       "//v8",
       "//v8:v8_libplatform",
     ]
+    if (pdf_enable_xfa) {
+      deps += [ "../../fxjs:gc" ]
+    }
   }
 }
 
@@ -356,9 +362,12 @@
     pdfium_fuzzer("pdf_formcalc_fuzzer") {
       sources = [ "pdf_formcalc_fuzzer.cc" ]
       deps = [
+        ":fuzzer_utils",
         "../../core/fxcrt",
+        "../../fxjs:gc",
         "../../xfa/fxfa/fm2js",
       ]
+      public_fuzzer = true
     }
 
     pdfium_fuzzer("pdfium_xfa_fuzzer") {
diff --git a/testing/fuzzers/pdf_formcalc_fuzzer.cc b/testing/fuzzers/pdf_formcalc_fuzzer.cc
index 08e22bb..ce502b4 100644
--- a/testing/fuzzers/pdf_formcalc_fuzzer.cc
+++ b/testing/fuzzers/pdf_formcalc_fuzzer.cc
@@ -4,13 +4,17 @@
 
 #include "core/fxcrt/cfx_widetextbuf.h"
 #include "core/fxcrt/fx_string.h"
+#include "testing/fuzzers/pdf_fuzzer_init_public.h"
+#include "testing/fuzzers/pdfium_fuzzer_util.h"
+#include "third_party/base/logging.h"
 #include "xfa/fxfa/fm2js/cxfa_fmparser.h"
 
 extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size) {
+  auto* state = static_cast<PDFFuzzerPublic*>(FPDF_GetFuzzerPerProcessState());
+  CHECK(state);
+  CHECK(state->GetHeap());
   WideString input = WideString::FromUTF8(ByteStringView(data, size));
-
   CXFA_FMParser parser(input.AsStringView());
   parser.Parse();
-
   return 0;
 }
diff --git a/testing/fuzzers/pdf_fuzzer_init_public.cc b/testing/fuzzers/pdf_fuzzer_init_public.cc
index ad39e36..ca4bb39 100644
--- a/testing/fuzzers/pdf_fuzzer_init_public.cc
+++ b/testing/fuzzers/pdf_fuzzer_init_public.cc
@@ -2,18 +2,16 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+#include "testing/fuzzers/pdf_fuzzer_init_public.h"
+
 #include <string.h>
 
-#include <memory>
-
-#include "public/fpdf_ext.h"
+#include "testing/fuzzers/pdfium_fuzzer_util.h"
 
 #ifdef PDF_ENABLE_V8
 #include "testing/free_deleter.h"
 #include "testing/v8_initializer.h"
-#include "v8/include/v8-platform.h"
-#include "v8/include/v8.h"
-#endif
+#endif  // PDF_ENABLE_V8
 
 #ifdef _WIN32
 #include <windows.h>
@@ -26,10 +24,13 @@
 
 namespace {
 
+// pdf_fuzzer_init.cc and pdf_fuzzer_init_public.cc are mutually exclusive
+// and should not be built together.
+PDFFuzzerInitPublic* g_instance = new PDFFuzzerInitPublic();
+
 #ifdef PDF_ENABLE_V8
 std::string ProgramPath() {
   std::string result;
-
 #ifdef _WIN32
   char path[MAX_PATH];
   DWORD len = GetModuleFileNameA(nullptr, path, MAX_PATH);
@@ -56,44 +57,41 @@
 
 }  // namespace
 
-// Initialize the library once for all runs of the fuzzer.
-struct TestCase {
-  TestCase() {
+PDFFuzzerPublic::PDFFuzzerPublic() {
 #ifdef PDF_ENABLE_V8
 #ifdef V8_USE_EXTERNAL_STARTUP_DATA
-    platform = InitializeV8ForPDFiumWithStartupData(
-        ProgramPath(), std::string(), std::string(), &snapshot_blob);
-#else
-    platform = InitializeV8ForPDFium(ProgramPath(), std::string());
+  platform_ = InitializeV8ForPDFiumWithStartupData(
+      ProgramPath(), std::string(), std::string(), &snapshot_blob_);
+#else   // V8_USE_EXTERNAL_STARTUP_DATA
+  platform_ = InitializeV8ForPDFium(ProgramPath(), std::string());
 #endif  // V8_USE_EXTERNAL_STARTUP_DATA
+#ifdef PDF_ENABLE_XFA
+  FXGC_Initialize(platform_.get(), nullptr);
+  heap_ = FXGC_CreateHeap();
+#endif  // PDF_ENABLE_XFA
 #endif  // PDF_ENABLE_V8
 
-    memset(&config, '\0', sizeof(config));
-    config.version = 3;
-    config.m_pUserFontPaths = nullptr;
-    config.m_pIsolate = nullptr;
-    config.m_v8EmbedderSlot = 0;
+  memset(&config_, '\0', sizeof(config_));
+  config_.version = 3;
+  config_.m_pUserFontPaths = nullptr;
+  config_.m_pIsolate = nullptr;
+  config_.m_v8EmbedderSlot = 0;
 #ifdef PDF_ENABLE_V8
-    config.m_pPlatform = platform.get();
+  config_.m_pPlatform = platform_.get();
 #endif  // PDF_ENABLE_V8
-    FPDF_InitLibraryWithConfig(&config);
+  FPDF_InitLibraryWithConfig(&config_);
 
-    memset(&unsupport_info, '\0', sizeof(unsupport_info));
-    unsupport_info.version = 1;
-    unsupport_info.FSDK_UnSupport_Handler = [](UNSUPPORT_INFO*, int) {};
-    FSDK_SetUnSpObjProcessHandler(&unsupport_info);
-  }
+  memset(&unsupport_info_, '\0', sizeof(unsupport_info_));
+  unsupport_info_.version = 1;
+  unsupport_info_.FSDK_UnSupport_Handler = [](UNSUPPORT_INFO*, int) {};
+  FSDK_SetUnSpObjProcessHandler(&unsupport_info_);
+}
 
-#ifdef PDF_ENABLE_V8
-  std::unique_ptr<v8::Platform> platform;
-  v8::StartupData snapshot_blob;
-#endif
+PDFFuzzerPublic::~PDFFuzzerPublic() = default;
 
-  FPDF_LIBRARY_CONFIG config;
-  UNSUPPORT_INFO unsupport_info;
-};
+PDFFuzzerInitPublic::PDFFuzzerInitPublic()
+    : context_(std::make_unique<PDFFuzzerPublic>()) {
+  FPDF_SetFuzzerPerProcessState(context_.get());
+}
 
-// pdf_fuzzer_init.cc and pdfium_fuzzer_init_public.cc are mutually exclusive
-// and should not be built together. They deliberately have the same global
-// variable.
-static TestCase* g_test_case = new TestCase();
+PDFFuzzerInitPublic::~PDFFuzzerInitPublic() = default;
diff --git a/testing/fuzzers/pdf_fuzzer_init_public.h b/testing/fuzzers/pdf_fuzzer_init_public.h
new file mode 100644
index 0000000..a66c2ff
--- /dev/null
+++ b/testing/fuzzers/pdf_fuzzer_init_public.h
@@ -0,0 +1,55 @@
+// Copyright 2020 The PDFium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef TESTING_FUZZERS_PDF_FUZZER_INIT_PUBLIC_H_
+#define TESTING_FUZZERS_PDF_FUZZER_INIT_PUBLIC_H_
+
+#include <memory>
+
+#include "public/fpdf_ext.h"
+#include "public/fpdfview.h"
+
+#ifdef PDF_ENABLE_V8
+#include "v8/include/v8-platform.h"
+#include "v8/include/v8.h"
+#ifdef PDF_ENABLE_XFA
+#include "fxjs/gc/heap.h"
+#endif  // PDF_ENABLE_XFA
+#endif  // PDF_ENABLE_V8
+
+// Context for all runs of the fuzzer.
+class PDFFuzzerPublic {
+ public:
+  PDFFuzzerPublic();
+  ~PDFFuzzerPublic();
+
+#ifdef PDF_ENABLE_V8
+#ifdef PDF_ENABLE_XFA
+  cppgc::Heap* GetHeap() { return heap_.get(); }
+#endif  // PDF_ENABLE_XFA
+#endif  // PDF_ENABLE_V8
+
+ private:
+  FPDF_LIBRARY_CONFIG config_;
+  UNSUPPORT_INFO unsupport_info_;
+#ifdef PDF_ENABLE_V8
+  std::unique_ptr<v8::Platform> platform_;
+  v8::StartupData snapshot_blob_;
+#ifdef PDF_ENABLE_XFA
+  FXGCScopedHeap heap_;
+#endif  // PDF_ENABLE_XFA
+#endif  // PDF_ENABLE_V8
+};
+
+// Initializes the library once for all runs of the fuzzer.
+class PDFFuzzerInitPublic {
+ public:
+  PDFFuzzerInitPublic();
+  ~PDFFuzzerInitPublic();
+
+ private:
+  std::unique_ptr<PDFFuzzerPublic> context_;
+};
+
+#endif  // TESTING_FUZZERS_PDF_FUZZER_INIT_PUBLIC_H_
diff --git a/testing/fuzzers/pdfium_fuzzer_util.cc b/testing/fuzzers/pdfium_fuzzer_util.cc
index 9238f0e..836244b 100644
--- a/testing/fuzzers/pdfium_fuzzer_util.cc
+++ b/testing/fuzzers/pdfium_fuzzer_util.cc
@@ -4,6 +4,18 @@
 
 #include "testing/fuzzers/pdfium_fuzzer_util.h"
 
+namespace {
+void* g_fuzzer_init_per_process_state = nullptr;
+}  // namespace
+
 int GetInteger(const uint8_t* data) {
   return data[0] | (data[1] << 8) | (data[2] << 16) | (data[3] << 24);
 }
+
+FPDF_EXPORT void FPDF_CALLCONV FPDF_SetFuzzerPerProcessState(void* state) {
+  g_fuzzer_init_per_process_state = state;
+}
+
+FPDF_EXPORT void* FPDF_CALLCONV FPDF_GetFuzzerPerProcessState() {
+  return g_fuzzer_init_per_process_state;
+}
diff --git a/testing/fuzzers/pdfium_fuzzer_util.h b/testing/fuzzers/pdfium_fuzzer_util.h
index d82f44b..a8ddeee 100644
--- a/testing/fuzzers/pdfium_fuzzer_util.h
+++ b/testing/fuzzers/pdfium_fuzzer_util.h
@@ -7,7 +7,19 @@
 
 #include <stdint.h>
 
+#include "public/fpdfview.h"
+
 // Returns an integer from the first 4 bytes of |data|.
 int GetInteger(const uint8_t* data);
 
+// Plumb access to any context created by fuzzer initialization into
+// the LLVMFuzzerTestOneInput() function, as that function does not
+// allow for additional parameters, nor can it reach back up to the
+// top-level fuzzer shim during a component build (see the comment
+// in BUILD.gn about splitting fuzzers into _impl and _src targets).
+extern "C" {
+FPDF_EXPORT void FPDF_CALLCONV FPDF_SetFuzzerPerProcessState(void* state);
+FPDF_EXPORT void* FPDF_CALLCONV FPDF_GetFuzzerPerProcessState();
+}  // extern "C"
+
 #endif  // TESTING_FUZZERS_PDFIUM_FUZZER_UTIL_H_