diff --git a/src/api/environment.cc b/src/api/environment.cc
index 5dfac00647ed..e5d06f27d131 100644
--- a/src/api/environment.cc
+++ b/src/api/environment.cc
@@ -1,4 +1,4 @@
-#include "env.h"
+#include "env-inl.h"
 #include "node.h"
 #include "node_context_data.h"
 #include "node_errors.h"
diff --git a/src/api/utils.cc b/src/api/utils.cc
index da7281a68f3b..3e59932f2f8b 100644
--- a/src/api/utils.cc
+++ b/src/api/utils.cc
@@ -1,3 +1,4 @@
+#include "env-inl.h"
 #include "node.h"
 #include "node_internals.h"
 #include "util-inl.h"
diff --git a/src/base_object.h b/src/base_object.h
index cb83462ff51e..f616108a1d94 100644
--- a/src/base_object.h
+++ b/src/base_object.h
@@ -24,7 +24,7 @@
 
 #if defined(NODE_WANT_INTERNALS) && NODE_WANT_INTERNALS
 
-#include "memory_tracker-inl.h"
+#include "memory_tracker.h"
 #include "v8.h"
 #include <type_traits>  // std::remove_reference
 
diff --git a/src/cares_wrap.cc b/src/cares_wrap.cc
index 07882a4212c6..0be02596f969 100644
--- a/src/cares_wrap.cc
+++ b/src/cares_wrap.cc
@@ -23,6 +23,7 @@
 #include "ares.h"
 #include "async_wrap-inl.h"
 #include "env-inl.h"
+#include "memory_tracker-inl.h"
 #include "node.h"
 #include "req_wrap-inl.h"
 #include "util-inl.h"
diff --git a/src/debug_utils.cc b/src/debug_utils.cc
index b86710fba6e8..a9bfa86b6d2a 100644
--- a/src/debug_utils.cc
+++ b/src/debug_utils.cc
@@ -1,4 +1,5 @@
 #include "debug_utils.h"
+#include "env-inl.h"
 #include "util-inl.h"
 
 #ifdef __POSIX__
diff --git a/src/debug_utils.h b/src/debug_utils.h
index ef5a4c0c4759..db01cacba6a1 100644
--- a/src/debug_utils.h
+++ b/src/debug_utils.h
@@ -4,7 +4,7 @@
 #if defined(NODE_WANT_INTERNALS) && NODE_WANT_INTERNALS
 
 #include "async_wrap.h"
-#include "env-inl.h"
+#include "env.h"
 
 #include <sstream>
 #include <string>
diff --git a/src/env.cc b/src/env.cc
index 5f408f18f146..bc43fac963bb 100644
--- a/src/env.cc
+++ b/src/env.cc
@@ -1,6 +1,7 @@
 #include "env.h"
 
 #include "async_wrap.h"
+#include "memory_tracker-inl.h"
 #include "node_buffer.h"
 #include "node_context_data.h"
 #include "node_errors.h"
diff --git a/src/heap_utils.cc b/src/heap_utils.cc
index ee0665cfe279..acc63fd1d9a1 100644
--- a/src/heap_utils.cc
+++ b/src/heap_utils.cc
@@ -1,4 +1,5 @@
 #include "env-inl.h"
+#include "memory_tracker-inl.h"
 #include "stream_base-inl.h"
 #include "util-inl.h"
 
diff --git a/src/inspector_agent.cc b/src/inspector_agent.cc
index d551c3a7d732..83f7140e93d7 100644
--- a/src/inspector_agent.cc
+++ b/src/inspector_agent.cc
@@ -1,5 +1,6 @@
 #include "inspector_agent.h"
 
+#include "env-inl.h"
 #include "inspector/main_thread_interface.h"
 #include "inspector/node_string.h"
 #include "inspector/runtime_agent.h"
diff --git a/src/inspector_js_api.cc b/src/inspector_js_api.cc
index 5caf3fa09a4d..9d6493857061 100644
--- a/src/inspector_js_api.cc
+++ b/src/inspector_js_api.cc
@@ -1,6 +1,7 @@
 #include "base_object-inl.h"
 #include "inspector_agent.h"
 #include "inspector_io.h"
+#include "memory_tracker-inl.h"
 #include "util-inl.h"
 #include "v8.h"
 #include "v8-inspector.h"
diff --git a/src/inspector_profiler.cc b/src/inspector_profiler.cc
index 4604e0a5b441..7e76ad778a0f 100644
--- a/src/inspector_profiler.cc
+++ b/src/inspector_profiler.cc
@@ -2,6 +2,7 @@
 #include <sstream>
 #include "base_object-inl.h"
 #include "debug_utils.h"
+#include "memory_tracker-inl.h"
 #include "node_file.h"
 #include "node_internals.h"
 #include "v8-inspector.h"
diff --git a/src/js_native_api_v8.cc b/src/js_native_api_v8.cc
index 286086ab6af4..da460e6b52b4 100644
--- a/src/js_native_api_v8.cc
+++ b/src/js_native_api_v8.cc
@@ -2,6 +2,7 @@
 #include <cmath>
 #include <algorithm>
 #define NAPI_EXPERIMENTAL
+#include "env-inl.h"
 #include "js_native_api_v8.h"
 #include "js_native_api.h"
 #include "util-inl.h"
diff --git a/src/module_wrap.cc b/src/module_wrap.cc
index a4e81dcc2947..e104afb736c2 100644
--- a/src/module_wrap.cc
+++ b/src/module_wrap.cc
@@ -1,6 +1,7 @@
 #include "module_wrap.h"
 
 #include "env.h"
+#include "memory_tracker-inl.h"
 #include "node_errors.h"
 #include "node_url.h"
 #include "util-inl.h"
diff --git a/src/node.cc b/src/node.cc
index 7dccd7ce5768..e5e9a23730f0 100644
--- a/src/node.cc
+++ b/src/node.cc
@@ -25,6 +25,7 @@
 
 #include "debug_utils.h"
 #include "env-inl.h"
+#include "memory_tracker-inl.h"
 #include "node_binding.h"
 #include "node_internals.h"
 #include "node_main_instance.h"
diff --git a/src/node_api.cc b/src/node_api.cc
index f8b0d8b55039..32393883d7c6 100644
--- a/src/node_api.cc
+++ b/src/node_api.cc
@@ -1,11 +1,12 @@
 #include <node_buffer.h>
-#include "env.h"
+#include "env-inl.h"
 #define NAPI_EXPERIMENTAL
 #include "js_native_api_v8.h"
 #include "node_api.h"
 #include "node_binding.h"
 #include "node_errors.h"
 #include "node_internals.h"
+#include "threadpoolwork-inl.h"
 #include "util-inl.h"
 
 #include <memory>
diff --git a/src/node_config.cc b/src/node_config.cc
index 335ebedc583b..92985dff2f8b 100644
--- a/src/node_config.cc
+++ b/src/node_config.cc
@@ -1,4 +1,5 @@
 #include "env-inl.h"
+#include "memory_tracker.h"
 #include "node.h"
 #include "node_i18n.h"
 #include "node_native_module_env.h"
diff --git a/src/node_constants.cc b/src/node_constants.cc
index aa2afc59d95e..7c9e4ce27611 100644
--- a/src/node_constants.cc
+++ b/src/node_constants.cc
@@ -19,6 +19,7 @@
 // OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
 // USE OR OTHER DEALINGS IN THE SOFTWARE.
 
+#include "env-inl.h"
 #include "node_constants.h"
 #include "node_internals.h"
 #include "util-inl.h"
diff --git a/src/node_contextify.cc b/src/node_contextify.cc
index 77622f8cbd6d..ee5a9db574f0 100644
--- a/src/node_contextify.cc
+++ b/src/node_contextify.cc
@@ -21,6 +21,7 @@
 
 #include "node_contextify.h"
 
+#include "memory_tracker-inl.h"
 #include "node_internals.h"
 #include "node_watchdog.h"
 #include "base_object-inl.h"
diff --git a/src/node_credentials.cc b/src/node_credentials.cc
index d384504f2ac9..6f99cf6641ee 100644
--- a/src/node_credentials.cc
+++ b/src/node_credentials.cc
@@ -1,3 +1,4 @@
+#include "env-inl.h"
 #include "node_internals.h"
 #include "util-inl.h"
 
diff --git a/src/node_crypto.cc b/src/node_crypto.cc
index bbb07e5b48b4..76a8cc8a193f 100644
--- a/src/node_crypto.cc
+++ b/src/node_crypto.cc
@@ -32,7 +32,9 @@
 #include "async_wrap-inl.h"
 #include "base_object-inl.h"
 #include "env-inl.h"
+#include "memory_tracker-inl.h"
 #include "string_bytes.h"
+#include "threadpoolwork-inl.h"
 #include "util-inl.h"
 #include "v8.h"
 
diff --git a/src/node_crypto_bio.cc b/src/node_crypto_bio.cc
index fcbe30ca9c07..9f06801c3ae2 100644
--- a/src/node_crypto_bio.cc
+++ b/src/node_crypto_bio.cc
@@ -20,6 +20,7 @@
 // USE OR OTHER DEALINGS IN THE SOFTWARE.
 
 #include "base_object-inl.h"
+#include "memory_tracker-inl.h"
 #include "node_crypto_bio.h"
 #include "openssl/bio.h"
 #include "util-inl.h"
diff --git a/src/node_file.cc b/src/node_file.cc
index 4da2a4f53cb5..8f82d639d6d0 100644
--- a/src/node_file.cc
+++ b/src/node_file.cc
@@ -21,6 +21,7 @@
 
 #include "node_file.h"
 #include "aliased_buffer.h"
+#include "memory_tracker-inl.h"
 #include "node_buffer.h"
 #include "node_process.h"
 #include "node_stat_watcher.h"
diff --git a/src/node_http2.cc b/src/node_http2.cc
index 0c650290c2b7..d9b886284ddd 100644
--- a/src/node_http2.cc
+++ b/src/node_http2.cc
@@ -1,5 +1,6 @@
 #include "aliased_buffer.h"
 #include "debug_utils.h"
+#include "memory_tracker-inl.h"
 #include "node.h"
 #include "node_buffer.h"
 #include "node_http2.h"
diff --git a/src/node_http_parser_llhttp.cc b/src/node_http_parser_llhttp.cc
index d2063873f17e..6e1d18d3af94 100644
--- a/src/node_http_parser_llhttp.cc
+++ b/src/node_http_parser_llhttp.cc
@@ -1,6 +1,7 @@
 #define NODE_EXPERIMENTAL_HTTP 1
 
 #include "node_http_parser_impl.h"
+#include "memory_tracker-inl.h"
 #include "node_metadata.h"
 #include "util-inl.h"
 
diff --git a/src/node_http_parser_traditional.cc b/src/node_http_parser_traditional.cc
index 7b413af8b6ce..11aa387f1098 100644
--- a/src/node_http_parser_traditional.cc
+++ b/src/node_http_parser_traditional.cc
@@ -2,6 +2,7 @@
 #undef NODE_EXPERIMENTAL_HTTP
 #endif
 
+#include "memory_tracker-inl.h"
 #include "node_http_parser_impl.h"
 #include "node_metadata.h"
 #include "util-inl.h"
diff --git a/src/node_internals.h b/src/node_internals.h
index cb039f297b19..f74e67ce6f07 100644
--- a/src/node_internals.h
+++ b/src/node_internals.h
@@ -24,7 +24,7 @@
 
 #if defined(NODE_WANT_INTERNALS) && NODE_WANT_INTERNALS
 
-#include "env-inl.h"
+#include "env.h"
 #include "node.h"
 #include "node_binding.h"
 #include "node_mutex.h"
@@ -252,27 +252,6 @@ class ThreadPoolWork {
   uv_work_t work_req_;
 };
 
-void ThreadPoolWork::ScheduleWork() {
-  env_->IncreaseWaitingRequestCounter();
-  int status = uv_queue_work(
-      env_->event_loop(),
-      &work_req_,
-      [](uv_work_t* req) {
-        ThreadPoolWork* self = ContainerOf(&ThreadPoolWork::work_req_, req);
-        self->DoThreadPoolWork();
-      },
-      [](uv_work_t* req, int status) {
-        ThreadPoolWork* self = ContainerOf(&ThreadPoolWork::work_req_, req);
-        self->env_->DecreaseWaitingRequestCounter();
-        self->AfterThreadPoolWork(status);
-      });
-  CHECK_EQ(status, 0);
-}
-
-int ThreadPoolWork::CancelWork() {
-  return uv_cancel(reinterpret_cast<uv_req_t*>(&work_req_));
-}
-
 #define TRACING_CATEGORY_NODE "node"
 #define TRACING_CATEGORY_NODE1(one)                                           \
     TRACING_CATEGORY_NODE ","                                                 \
diff --git a/src/node_messaging.cc b/src/node_messaging.cc
index ea7b48779ca1..fa583a257031 100644
--- a/src/node_messaging.cc
+++ b/src/node_messaging.cc
@@ -2,6 +2,7 @@
 
 #include "async_wrap-inl.h"
 #include "debug_utils.h"
+#include "memory_tracker-inl.h"
 #include "node_contextify.h"
 #include "node_buffer.h"
 #include "node_errors.h"
diff --git a/src/node_perf.cc b/src/node_perf.cc
index 086320203000..f43c10213624 100644
--- a/src/node_perf.cc
+++ b/src/node_perf.cc
@@ -1,4 +1,5 @@
 #include "aliased_buffer.h"
+#include "memory_tracker-inl.h"
 #include "node_internals.h"
 #include "node_perf.h"
 #include "node_buffer.h"
diff --git a/src/node_report.cc b/src/node_report.cc
index 578da4376e07..2f668b546307 100644
--- a/src/node_report.cc
+++ b/src/node_report.cc
@@ -1,3 +1,4 @@
+#include "env-inl.h"
 #include "node_report.h"
 #include "debug_utils.h"
 #include "node_internals.h"
diff --git a/src/node_report_utils.cc b/src/node_report_utils.cc
index 33d7c52b34f7..2581af06fac6 100644
--- a/src/node_report_utils.cc
+++ b/src/node_report_utils.cc
@@ -1,3 +1,4 @@
+#include "env-inl.h"
 #include "node_internals.h"
 #include "node_report.h"
 #include "util-inl.h"
diff --git a/src/node_stat_watcher.cc b/src/node_stat_watcher.cc
index b7fb45900f9b..ae30825cbbdb 100644
--- a/src/node_stat_watcher.cc
+++ b/src/node_stat_watcher.cc
@@ -19,6 +19,7 @@
 // OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
 // USE OR OTHER DEALINGS IN THE SOFTWARE.
 
+#include "memory_tracker-inl.h"
 #include "node_stat_watcher.h"
 #include "async_wrap-inl.h"
 #include "env.h"
diff --git a/src/node_trace_events.cc b/src/node_trace_events.cc
index 13072a3340ce..24e1d66fb7e7 100644
--- a/src/node_trace_events.cc
+++ b/src/node_trace_events.cc
@@ -1,5 +1,6 @@
 #include "base_object-inl.h"
 #include "env.h"
+#include "memory_tracker-inl.h"
 #include "node.h"
 #include "node_internals.h"
 #include "node_v8_platform-inl.h"
diff --git a/src/node_url.h b/src/node_url.h
index e85b14e2bdf3..e85ca6e7129f 100644
--- a/src/node_url.h
+++ b/src/node_url.h
@@ -4,7 +4,7 @@
 #if defined(NODE_WANT_INTERNALS) && NODE_WANT_INTERNALS
 
 #include "node.h"
-#include "env-inl.h"
+#include "env.h"
 
 #include <string>
 
diff --git a/src/node_watchdog.cc b/src/node_watchdog.cc
index 28df2fb44983..63fa88702499 100644
--- a/src/node_watchdog.cc
+++ b/src/node_watchdog.cc
@@ -19,11 +19,13 @@
 // OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
 // USE OR OTHER DEALINGS IN THE SOFTWARE.
 
-#include "node_watchdog.h"
 #include <algorithm>
+
 #include "debug_utils.h"
+#include "env-inl.h"
 #include "node_errors.h"
 #include "node_internals.h"
+#include "node_watchdog.h"
 #include "util-inl.h"
 
 namespace node {
diff --git a/src/node_worker.cc b/src/node_worker.cc
index 20b883664da2..e84b36f132ae 100644
--- a/src/node_worker.cc
+++ b/src/node_worker.cc
@@ -1,5 +1,6 @@
 #include "node_worker.h"
 #include "debug_utils.h"
+#include "memory_tracker-inl.h"
 #include "node_errors.h"
 #include "node_buffer.h"
 #include "node_options-inl.h"
diff --git a/src/node_zlib.cc b/src/node_zlib.cc
index f38925788221..30fef0ff1d4d 100644
--- a/src/node_zlib.cc
+++ b/src/node_zlib.cc
@@ -19,11 +19,13 @@
 // OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
 // USE OR OTHER DEALINGS IN THE SOFTWARE.
 
+#include "memory_tracker-inl.h"
 #include "node.h"
 #include "node_buffer.h"
 
 #include "async_wrap-inl.h"
 #include "env-inl.h"
+#include "threadpoolwork-inl.h"
 #include "util-inl.h"
 
 #include "v8.h"
diff --git a/src/threadpoolwork-inl.h b/src/threadpoolwork-inl.h
new file mode 100644
index 000000000000..8bba988b18db
--- /dev/null
+++ b/src/threadpoolwork-inl.h
@@ -0,0 +1,57 @@
+// Copyright Joyent, Inc. and other Node contributors.
+//
+// Permission is hereby granted, free of charge, to any person obtaining a
+// copy of this software and associated documentation files (the
+// "Software"), to deal in the Software without restriction, including
+// without limitation the rights to use, copy, modify, merge, publish,
+// distribute, sublicense, and/or sell copies of the Software, and to permit
+// persons to whom the Software is furnished to do so, subject to the
+// following conditions:
+//
+// The above copyright notice and this permission notice shall be included
+// in all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
+// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
+// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
+// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
+// USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+#ifndef SRC_THREADPOOLWORK_INL_H_
+#define SRC_THREADPOOLWORK_INL_H_
+
+#if defined(NODE_WANT_INTERNALS) && NODE_WANT_INTERNALS
+
+#include "util-inl.h"
+#include "node_internals.h"
+
+namespace node {
+
+void ThreadPoolWork::ScheduleWork() {
+  env_->IncreaseWaitingRequestCounter();
+  int status = uv_queue_work(
+      env_->event_loop(),
+      &work_req_,
+      [](uv_work_t* req) {
+        ThreadPoolWork* self = ContainerOf(&ThreadPoolWork::work_req_, req);
+        self->DoThreadPoolWork();
+      },
+      [](uv_work_t* req, int status) {
+        ThreadPoolWork* self = ContainerOf(&ThreadPoolWork::work_req_, req);
+        self->env_->DecreaseWaitingRequestCounter();
+        self->AfterThreadPoolWork(status);
+      });
+  CHECK_EQ(status, 0);
+}
+
+int ThreadPoolWork::CancelWork() {
+  return uv_cancel(reinterpret_cast<uv_req_t*>(&work_req_));
+}
+
+}  // namespace node
+
+#endif  // defined(NODE_WANT_INTERNALS) && NODE_WANT_INTERNALS
+
+#endif  // SRC_THREADPOOLWORK_INL_H_
diff --git a/src/tls_wrap.cc b/src/tls_wrap.cc
index cd6321b9693c..22996f9bcffa 100644
--- a/src/tls_wrap.cc
+++ b/src/tls_wrap.cc
@@ -22,6 +22,7 @@
 #include "tls_wrap.h"
 #include "async_wrap-inl.h"
 #include "debug_utils.h"
+#include "memory_tracker-inl.h"
 #include "node_buffer.h"  // Buffer
 #include "node_crypto.h"  // SecureContext
 #include "node_crypto_bio.h"  // NodeBIO
diff --git a/src/util.cc b/src/util.cc
index 51f11b45396f..26dbfe844995 100644
--- a/src/util.cc
+++ b/src/util.cc
@@ -22,6 +22,7 @@
 #include "util.h"  // NOLINT(build/include_inline)
 #include "util-inl.h"
 
+#include "env-inl.h"
 #include "node_buffer.h"
 #include "node_errors.h"
 #include "node_internals.h"
diff --git a/test/cctest/node_test_fixture.h b/test/cctest/node_test_fixture.h
index f5740e5ce927..a396f14d18c6 100644
--- a/test/cctest/node_test_fixture.h
+++ b/test/cctest/node_test_fixture.h
@@ -7,7 +7,7 @@
 #include "node.h"
 #include "node_platform.h"
 #include "node_internals.h"
-#include "env.h"
+#include "env-inl.h"
 #include "util-inl.h"
 #include "v8.h"
 #include "libplatform/libplatform.h"
diff --git a/test/cctest/test_aliased_buffer.cc b/test/cctest/test_aliased_buffer.cc
index 5421dd6d1458..ba947700c1bf 100644
--- a/test/cctest/test_aliased_buffer.cc
+++ b/test/cctest/test_aliased_buffer.cc
@@ -1,4 +1,3 @@
-
 #include "v8.h"
 #include "aliased_buffer.h"
 #include "node_test_fixture.h"
diff --git a/test/cctest/test_url.cc b/test/cctest/test_url.cc
index ddef534b5748..96f974138636 100644
--- a/test/cctest/test_url.cc
+++ b/test/cctest/test_url.cc
@@ -1,5 +1,6 @@
 #include "node_url.h"
 #include "node_i18n.h"
+#include "util-inl.h"
 
 #include "gtest/gtest.h"
 
diff --git a/tools/js2c.py b/tools/js2c.py
index 9c5130a91630..413158765551 100755
--- a/tools/js2c.py
+++ b/tools/js2c.py
@@ -177,6 +177,7 @@ def ReadMacros(macro_files):
 
 
 TEMPLATE = """
+#include "env-inl.h"
 #include "node_native_module.h"
 #include "node_internals.h"
 
diff --git a/tools/snapshot/node_mksnapshot.cc b/tools/snapshot/node_mksnapshot.cc
index c273ba20b610..5cf24f32b49e 100644
--- a/tools/snapshot/node_mksnapshot.cc
+++ b/tools/snapshot/node_mksnapshot.cc
@@ -5,9 +5,11 @@
 #include <string>
 #include <vector>
 
+#include "env-inl.h"
 #include "libplatform/libplatform.h"
 #include "node_internals.h"
 #include "snapshot_builder.h"
+#include "util-inl.h"
 #include "v8.h"
 
 #ifdef _WIN32