diff --git a/tools/mac/on_demand_service_tool.mm b/tools/mac/on_demand_service_tool.mm
index 70de1b5..7b3e104 100644
--- a/tools/mac/on_demand_service_tool.mm
+++ b/tools/mac/on_demand_service_tool.mm
@@ -152,13 +152,12 @@
               dictionaryWithCapacity:options.mach_services.size()];
           for (std::string mach_service : options.mach_services) {
             NSString* mach_service_ns = base::SysUTF8ToNSString(mach_service);
-            [mach_services setObject:@YES forKey:mach_service_ns];
+            mach_services[mach_service_ns] = @YES;
           }
 
           NSMutableDictionary* mutable_job_dictionary =
               [[job_dictionary mutableCopy] autorelease];
-          [mutable_job_dictionary setObject:mach_services
-                                     forKey:@LAUNCH_JOBKEY_MACHSERVICES];
+          mutable_job_dictionary[@LAUNCH_JOBKEY_MACHSERVICES] = mach_services;
           job_dictionary = mutable_job_dictionary;
         }
 
diff --git a/util/mac/launchd.mm b/util/mac/launchd.mm
index ef5a606..37748ee 100644
--- a/util/mac/launchd.mm
+++ b/util/mac/launchd.mm
@@ -45,7 +45,7 @@
         }
 
         CFPropertyListRef value_cf =
-            implicit_cast<CFPropertyListRef>([dictionary_ns objectForKey:key]);
+            implicit_cast<CFPropertyListRef>(dictionary_ns[key]);
         launch_data_t value_launch = CFPropertyToLaunchData(value_cf);
         if (!value_launch) {
           return nullptr;
diff --git a/util/mac/launchd_test.mm b/util/mac/launchd_test.mm
index b793a9b..6b51ee2 100644
--- a/util/mac/launchd_test.mm
+++ b/util/mac/launchd_test.mm
@@ -78,14 +78,14 @@
       @0.0,
       @1.0,
       @-1.0,
-      [NSNumber numberWithFloat:std::numeric_limits<float>::min()],
-      [NSNumber numberWithFloat:std::numeric_limits<float>::max()],
-      [NSNumber numberWithDouble:std::numeric_limits<double>::min()],
-      [NSNumber numberWithDouble:std::numeric_limits<double>::max()],
+      @(std::numeric_limits<float>::min()),
+      @(std::numeric_limits<float>::max()),
+      @(std::numeric_limits<double>::min()),
+      @(std::numeric_limits<double>::max()),
       @3.1415926535897932,
-      [NSNumber numberWithDouble:std::numeric_limits<double>::infinity()],
-      [NSNumber numberWithDouble:std::numeric_limits<double>::quiet_NaN()],
-      [NSNumber numberWithDouble:std::numeric_limits<double>::signaling_NaN()],
+      @(std::numeric_limits<double>::infinity()),
+      @(std::numeric_limits<double>::quiet_NaN()),
+      @(std::numeric_limits<double>::signaling_NaN()),
     };
 
     for (size_t index = 0; index < base::size(double_nses); ++index) {
diff --git a/util/net/http_transport_mac.mm b/util/net/http_transport_mac.mm
index 8faa1b8..b9be11c 100644
--- a/util/net/http_transport_mac.mm
+++ b/util/net/http_transport_mac.mm
@@ -52,13 +52,11 @@
 
   // CFNetwork would use the main bundle’s CFBundleName, or the main
   // executable’s filename if none.
-  user_agent = AppendEscapedFormat(
-      user_agent, @"%@", [NSString stringWithUTF8String:PACKAGE_NAME]);
+  user_agent = AppendEscapedFormat(user_agent, @"%@", @PACKAGE_NAME);
 
   // CFNetwork would use the main bundle’s CFBundleVersion, or the string
   // “(unknown version)” if none.
-  user_agent = AppendEscapedFormat(
-      user_agent, @"/%@", [NSString stringWithUTF8String:PACKAGE_VERSION]);
+  user_agent = AppendEscapedFormat(user_agent, @"/%@", @PACKAGE_VERSION);
 
   // Expected to be CFNetwork.
   NSBundle* nsurl_bundle = [NSBundle bundleForClass:[NSURLRequest class]];
@@ -78,10 +76,8 @@
   if (uname(&os) != 0) {
     PLOG(WARNING) << "uname";
   } else {
-    user_agent = AppendEscapedFormat(
-        user_agent, @" %@", [NSString stringWithUTF8String:os.sysname]);
-    user_agent = AppendEscapedFormat(
-        user_agent, @"/%@", [NSString stringWithUTF8String:os.release]);
+    user_agent = AppendEscapedFormat(user_agent, @" %@", @(os.sysname));
+    user_agent = AppendEscapedFormat(user_agent, @"/%@", @(os.release));
 
     // CFNetwork just uses the equivalent of os.machine to obtain the native
     // (kernel) architecture. Here, give the process’ architecture as well as
@@ -98,7 +94,7 @@
 #endif
     user_agent = AppendEscapedFormat(user_agent, @" (%@", arch);
 
-    NSString* machine = [NSString stringWithUTF8String:os.machine];
+    NSString* machine = @(os.machine);
     if (![machine isEqualToString:arch]) {
       user_agent = AppendEscapedFormat(user_agent, @"; %@", machine);
     }