diff --git a/packages/grpc-native-core/binding.gyp b/packages/grpc-native-core/binding.gyp
index 6c0a986d..3e858e18 100644
--- a/packages/grpc-native-core/binding.gyp
+++ b/packages/grpc-native-core/binding.gyp
@@ -91,7 +91,8 @@
       'GPR_BACKWARDS_COMPATIBILITY_MODE',
       'GRPC_ARES=0',
       'GRPC_UV',
-      'GRPC_NODE_VERSION="1.16.0-pre1"'
+      'GRPC_NODE_VERSION="1.16.0-pre1"',
+      '_XOPEN_SOURCE=500'
     ],
     'conditions': [
       ['grpc_gcov=="true"', {
@@ -118,11 +119,6 @@
           'GPR_MUSL_LIBC_COMPAT'
         ]
       }],
-      ['OS!="win" and runtime=="electron"', {
-        "defines": [
-          'OPENSSL_NO_THREADS'
-        ]
-      }],
       # This is the condition for using boringssl
       ['OS=="win" or runtime=="electron"', {
         "include_dirs": [
diff --git a/packages/grpc-native-core/templates/binding.gyp.template b/packages/grpc-native-core/templates/binding.gyp.template
index f9abaa7c..a9ba8507 100644
--- a/packages/grpc-native-core/templates/binding.gyp.template
+++ b/packages/grpc-native-core/templates/binding.gyp.template
@@ -83,7 +83,8 @@
         'GPR_BACKWARDS_COMPATIBILITY_MODE',
         'GRPC_ARES=0',
         'GRPC_UV',
-        'GRPC_NODE_VERSION="${settings.get('node_version', settings.version)}"'
+        'GRPC_NODE_VERSION="${settings.get('node_version', settings.version)}"',
+        '_XOPEN_SOURCE=500'
       ],
       'conditions': [
         ['grpc_gcov=="true"', {
@@ -102,11 +103,6 @@
             'GPR_MUSL_LIBC_COMPAT'
           ]
         }],
-        ['OS!="win" and runtime=="electron"', {
-          "defines": [
-            'OPENSSL_NO_THREADS'
-          ]
-        }],
         # This is the condition for using boringssl
         ['OS=="win" or runtime=="electron"', {
           "include_dirs": [