diff --git a/Library/Homebrew/services/system/systemctl.rb b/Library/Homebrew/services/system/systemctl.rb
index a7a8d912cb..aa2fc1150b 100644
--- a/Library/Homebrew/services/system/systemctl.rb
+++ b/Library/Homebrew/services/system/systemctl.rb
@@ -29,7 +29,7 @@ module Services
         _run(*args, mode: :read)
       end
 
-      sig { params(args: T.any(String, Pathname), mode: T.nilable(Symbol)).returns(T.untyped) }
+      sig { params(args: T.nilable(T.any(String, Pathname)), mode: T.nilable(Symbol)).returns(T.untyped) }
       private_class_method def self._run(*args, mode:)
         require "system_command"
         result = SystemCommand.run(executable,
diff --git a/Library/Homebrew/test/services/cli_spec.rb b/Library/Homebrew/test/services/cli_spec.rb
index 6d9c002a41..8deb774b3f 100644
--- a/Library/Homebrew/test/services/cli_spec.rb
+++ b/Library/Homebrew/test/services/cli_spec.rb
@@ -177,7 +177,7 @@ RSpec.describe Services::Cli do
 
   describe "#systemd_load", :needs_linux do
     it "checks non-enabling run" do
-      expect(Services::System::Systemctl).to receive(:executable).once.and_return("/bin/systemctl")
+      expect(Services::System::Systemctl).to receive(:executable).once.and_return(Pathname.new("/usr/bin/systemctl"))
       expect(Services::System::Systemctl).to receive(:scope).once.and_return("--user")
       services_cli.systemd_load(
         instance_double(Services::FormulaWrapper, service_name: "name"),
@@ -186,7 +186,7 @@ RSpec.describe Services::Cli do
     end
 
     it "checks enabling run" do
-      expect(Services::System::Systemctl).to receive(:executable).twice.and_return("/bin/systemctl")
+      expect(Services::System::Systemctl).to receive(:executable).once.and_return(Pathname.new("/usr/bin/systemctl"))
       expect(Services::System::Systemctl).to receive(:scope).twice.and_return("--user")
       services_cli.systemd_load(
         instance_double(Services::FormulaWrapper, service_name: "name"),
@@ -198,14 +198,14 @@ RSpec.describe Services::Cli do
   describe "#launchctl_load", :needs_macos do
     it "checks non-enabling run" do
       expect(Services::System).to receive(:domain_target).once.and_return("target")
-      expect(Services::System).to receive(:launchctl).once.and_return("/bin/launchctl")
+      expect(Services::System).to receive(:launchctl).once.and_return(Pathname.new("/bin/launchctl"))
       expect(described_class).to receive(:safe_system).once.and_return(true)
       services_cli.launchctl_load(instance_double(Services::FormulaWrapper), file: "a", enable: false)
     end
 
     it "checks enabling run" do
       expect(Services::System).to receive(:domain_target).twice.and_return("target")
-      expect(Services::System).to receive(:launchctl).twice.and_return("/bin/launchctl")
+      expect(Services::System).to receive(:launchctl).once.and_return(Pathname.new("/bin/launchctl"))
       expect(described_class).to receive(:safe_system).twice.and_return(true)
       services_cli.launchctl_load(instance_double(Services::FormulaWrapper, service_name: "name"), file:   "a",
                                                                                                    enable: true)
diff --git a/Library/Homebrew/test/services/system/systemctl_spec.rb b/Library/Homebrew/test/services/system/systemctl_spec.rb
index 5a17d8632f..6c2a7f6783 100644
--- a/Library/Homebrew/test/services/system/systemctl_spec.rb
+++ b/Library/Homebrew/test/services/system/systemctl_spec.rb
@@ -18,7 +18,7 @@ RSpec.describe Services::System::Systemctl do
 
   describe ".executable" do
     it "outputs systemctl command location", :needs_linux do
-      expect(described_class.executable).to eq("/bin/systemctl")
+      expect(described_class.executable).to eq(Pathname.new("/usr/bin/systemctl"))
     end
   end
 end