--- a/base/BUILD.gn
+++ b/base/BUILD.gn
@@ -38,8 +38,6 @@
 import("//build/config/sysroot.gni")
 import("//build/config/ui.gni")
 import("//build/nocompile.gni")
-import("//build/rust/rust_bindgen.gni")
-import("//build/rust/rust_static_library.gni")
 import("//build/timestamp.gni")
 import("//build/util/process_version.gni")
 import("//build_overrides/build.gni")
@@ -1022,11 +1020,6 @@
     # Used by metrics/crc32, except on NaCl builds.
     deps += [ "//third_party/zlib" ]
 
-    # NaCl does not support Rust.
-    deps += [
-      ":rust_logger",
-      "//third_party/rust/serde_json_lenient/v0_2/wrapper",
-    ]
   }
 
   # `raw_ptr` cannot be made a component due to CRT symbol issues.
@@ -1063,7 +1056,7 @@
     "//third_party/abseil-cpp:absl",
   ]
 
-  if (!is_nacl) {
+  if (is_nacl) {
     sources += [
       "containers/span_rust.h",
       "strings/string_view_rust.h",
@@ -1543,8 +1536,6 @@
       "files/scoped_temp_file.h",
       "json/json_file_value_serializer.cc",
       "json/json_file_value_serializer.h",
-      "logging/rust_log_integration.cc",
-      "logging/rust_log_integration.h",
       "memory/discardable_memory.cc",
       "memory/discardable_memory.h",
       "memory/discardable_memory_allocator.cc",
@@ -2447,40 +2438,6 @@
   }
 }
 
-rust_bindgen("logging_log_severity_bindgen") {
-  # TODO(danakj): Maybe combine all base bindgen targets, or all base/logging
-  # ones even) into a single GN target? But the GN rule needs to handle multiple
-  # headers then.
-  header = "logging/log_severity.h"
-  cpp = true
-  visibility = [ ":*" ]
-
-  # Transitive generated header dependency.
-  deps = [ ":debugging_buildflags" ]
-}
-
-rust_bindgen("logging_rust_log_integration_bindgen") {
-  header = "logging/rust_log_integration.h"
-  cpp = true
-  visibility = [ ":*" ]
-
-  # Transitive generated header dependency.
-  deps = [ ":debugging_buildflags" ]
-}
-
-rust_static_library("rust_logger") {
-  allow_unsafe = true  # Unsafe needed for FFI.
-  deps = [
-    ":logging_log_severity_bindgen",
-    ":logging_rust_log_integration_bindgen",
-    "//third_party/rust/log/v0_4:lib",
-  ]
-  visibility = [ ":base" ]
-  sources = [ "logging/rust_logger.rs" ]
-  crate_root = "logging/rust_logger.rs"
-
-  cxx_bindings = [ "logging/rust_logger.rs" ]
-}
 
 if (is_linux || is_chromeos) {
   # Split out as a separate target for two reasons:
@@ -3564,7 +3521,7 @@
     sources += [ "location_unittest.cc" ]
   }
 
-  if (!is_nacl) {
+  if (is_nacl) {
     sources += [
       "containers/span_rust_unittest.cc",
       "strings/string_piece_rust_unittest.cc",
@@ -3617,7 +3574,7 @@
     deps += [ "allocator/partition_allocator/src/partition_alloc:unittests" ]
   }
 
-  if (!is_nacl) {
+  if (is_nacl) {
     deps += [ "//build/rust:cxx_cppdeps" ]
   }
 
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -28,7 +28,6 @@
 import("//gpu/vulkan/features.gni")
 import("//media/gpu/args.gni")
 import("//media/media_options.gni")
-import("//mojo/public/rust/rust.gni")
 import("//pdf/features.gni")
 import("//ppapi/buildflags/buildflags.gni")
 import("//printing/buildflags/buildflags.gni")
@@ -888,12 +887,9 @@
 
   deps = [
     ":rust_build_tests",
-    "//base:base_unittests",  # There is rust stuff in here.
-    "//testing/rust_gtest_interop:rust_gtest_interop_unittests",
-    "//third_party/cloud_authenticator/processor",
   ]
 
-  if (enable_rust_mojo) {
+  if (false) {
     deps += [
       "//mojo/public/rust:mojo_rust",
       "//mojo/public/rust:mojo_rust_integration_unittests",
--- a/base/test/BUILD.gn
+++ b/base/test/BUILD.gn
@@ -7,7 +7,6 @@
 import("//build/config/features.gni")
 import("//build/config/nacl/config.gni")
 import("//build/config/ui.gni")
-import("//build/rust/rust_static_library.gni")
 import("//build_overrides/build.gni")
 import("//third_party/protobuf/proto_library.gni")
 
@@ -39,16 +38,6 @@
   ]
 }
 
-rust_static_library("test_rust_logger_consumer") {
-  allow_unsafe = true  # Unsafe needed for FFI
-  testonly = true
-  deps = [ "//third_party/rust/log/v0_4:lib" ]
-  sources = [ "logging/test_rust_logger_consumer.rs" ]
-
-  crate_root = "logging/test_rust_logger_consumer.rs"
-
-  cxx_bindings = [ "logging/test_rust_logger_consumer.rs" ]
-}
 
 static_library("test_support") {
   testonly = true
@@ -189,7 +178,6 @@
 
   public_deps = [
     ":test_config",
-    ":test_rust_logger_consumer",
     "//base",
     "//base:base_static",
     "//base:i18n",
--- a/third_party/blink/common/BUILD.gn
+++ b/third_party/blink/common/BUILD.gn
@@ -341,7 +341,6 @@
     "//services/metrics/public/cpp:ukm_builders",
     "//services/metrics/public/mojom:mojom",
     "//services/network/public/cpp:cpp",
-    "//third_party/blink/common/rust_crash",
     "//third_party/blink/public/common:buildflags",
     "//third_party/re2",
     "//ui/base:base",
--- a/third_party/breakpad/BUILD.gn
+++ b/third_party/breakpad/BUILD.gn
@@ -494,11 +494,6 @@
       # For breakpad/src/common/stabs_reader.h.
       defines = [ "HAVE_MACH_O_NLIST_H" ]
 
-      # Rust demangle support.
-      deps = [ "//third_party/rust/rustc_demangle_capi/v0_1:lib" ]
-      defines += [ "HAVE_RUSTC_DEMANGLE" ]
-      include_dirs += [ "//third_party/rust/chromium_crates_io/vendor/rustc-demangle-capi-0.1.0/include" ]
-      sources += [ "//third_party/rust/chromium_crates_io/vendor/rustc-demangle-capi-0.1.0/include/rustc_demangle.h" ]
     }
     test("breakpad_unittests") {
       sources = [ "breakpad/src/common/module_unittest.cc" ]
@@ -742,11 +737,6 @@
 
       include_dirs = [ "breakpad/src" ]
 
-      # Rust demangle support.
-      deps = [ "//third_party/rust/rustc_demangle_capi/v0_1:lib" ]
-      defines += [ "HAVE_RUSTC_DEMANGLE" ]
-      include_dirs += [ "//third_party/rust/chromium_crates_io/vendor/rustc-demangle-capi-0.1.0/include" ]
-      sources += [ "//third_party/rust/chromium_crates_io/vendor/rustc-demangle-capi-0.1.0/include/rustc_demangle.h" ]
 
       libs = [ "z" ]
     }
--- a/base/json/json_reader.cc
+++ b/base/json/json_reader.cc
@@ -13,7 +13,7 @@
 #include "base/metrics/histogram_macros.h"
 #include "build/build_config.h"
 
-#if !BUILDFLAG(IS_NACL)
+#if BUILDFLAG(IS_NACL)
 #include "base/strings/string_view_rust.h"
 #include "third_party/rust/serde_json_lenient/v0_2/wrapper/functions.h"
 #include "third_party/rust/serde_json_lenient/v0_2/wrapper/lib.rs.h"
@@ -23,7 +23,7 @@
 
 // TODO(crbug.com/40811643): Move the C++ parser into components/nacl to just
 // run in-process there. Don't compile base::JSONReader on NaCL at all.
-#if !BUILDFLAG(IS_NACL)
+#if BUILDFLAG(IS_NACL)
 
 namespace {
 using serde_json_lenient::ContextPointer;
@@ -140,7 +140,7 @@
 std::optional<Value> JSONReader::Read(std::string_view json,
                                       int options,
                                       size_t max_depth) {
-#if BUILDFLAG(IS_NACL)
+#if !BUILDFLAG(IS_NACL)
   internal::JSONParser parser(options, max_depth);
   return parser.Parse(json);
 #else   // BUILDFLAG(IS_NACL)
@@ -173,7 +173,7 @@
 JSONReader::Result JSONReader::ReadAndReturnValueWithError(
     std::string_view json,
     int options) {
-#if BUILDFLAG(IS_NACL)
+#if !BUILDFLAG(IS_NACL)
   internal::JSONParser parser(options);
   auto value = parser.Parse(json);
   if (!value) {
@@ -213,7 +213,7 @@
   if (!base::FeatureList::GetInstance()) {
     return false;
   }
-#if BUILDFLAG(IS_NACL)
+#if !BUILDFLAG(IS_NACL)
   return false;
 #else
   return base::FeatureList::IsEnabled(base::features::kUseRustJsonParser);
--- a/base/logging.cc
+++ b/base/logging.cc
@@ -126,7 +126,7 @@
 #include "base/fuchsia/scoped_fx_logger.h"
 #endif
 
-#if !BUILDFLAG(IS_NACL)
+#if BUILDFLAG(IS_NACL)
 #include "base/logging/rust_logger.rs.h"
 #endif
 
@@ -526,7 +526,7 @@
   }
 #endif
 
-#if !BUILDFLAG(IS_NACL)
+#if BUILDFLAG(IS_NACL)
   // Connects Rust logging with the //base logging functionality.
   internal::init_rust_log_crate();
 #endif
--- a/third_party/blink/common/chrome_debug_urls.cc
+++ b/third_party/blink/common/chrome_debug_urls.cc
@@ -11,7 +11,6 @@
 #include "base/threading/platform_thread.h"
 #include "build/build_config.h"
 #include "third_party/blink/common/crash_helpers.h"
-#include "third_party/blink/common/rust_crash/src/lib.rs.h"
 #include "url/gurl.h"
 
 #if BUILDFLAG(IS_WIN)
@@ -117,7 +116,7 @@
     // Ensure that ASAN works even in Rust code.
     LOG(ERROR) << "Intentionally causing ASAN heap overflow in Rust"
                << " because user navigated to " << url.spec();
-    crash_in_rust_with_overflow();
+    //crash_in_rust_with_overflow();
   }
 }
 #endif  // ADDRESS_SANITIZER
@@ -137,7 +136,7 @@
   } else if (url == kChromeUICrashRustURL) {
     // Cause a typical crash in Rust code, so we can test that call stack
     // collection and symbol mangling work across the language boundary.
-    crash_in_rust();
+    //crash_in_rust();
   } else if (url == kChromeUIDumpURL) {
     // This URL will only correctly create a crash dump file if content is
     // hosted in a process that has correctly called