diff --git a/src/BizHawk.Client.Common/Api/Interfaces/IEmuClientApi.cs b/src/BizHawk.Client.Common/Api/Interfaces/IEmuClientApi.cs
index d401eafa43..fe25565484 100644
--- a/src/BizHawk.Client.Common/Api/Interfaces/IEmuClientApi.cs
+++ b/src/BizHawk.Client.Common/Api/Interfaces/IEmuClientApi.cs
@@ -46,9 +46,7 @@ namespace BizHawk.Client.Common
 
 		void ClearAutohold();
 
-		void CloseEmulator();
-
-		void CloseEmulatorWithCode(int exitCode);
+		void CloseEmulator(int? exitCode = null);
 
 		void CloseRom();
 
diff --git a/src/BizHawk.Client.EmuHawk/Api/ClientApi.cs b/src/BizHawk.Client.EmuHawk/Api/ClientApi.cs
index cbe0799f08..d68e4e221f 100644
--- a/src/BizHawk.Client.EmuHawk/Api/ClientApi.cs
+++ b/src/BizHawk.Client.EmuHawk/Api/ClientApi.cs
@@ -64,8 +64,8 @@ namespace BizHawk.Client.EmuHawk
 		/// <inheritdoc cref="IEmuClientApi.CloseEmulator"/>
 		public static void CloseEmulator() => GlobalWin.ClientApi.CloseEmulator();
 
-		/// <inheritdoc cref="IEmuClientApi.CloseEmulatorWithCode"/>
-		public static void CloseEmulatorWithCode(int exitCode) => GlobalWin.ClientApi.CloseEmulatorWithCode(exitCode);
+		/// <inheritdoc cref="IEmuClientApi.CloseEmulator"/>
+		public static void CloseEmulatorWithCode(int exitCode) => GlobalWin.ClientApi.CloseEmulator(exitCode);
 
 		/// <inheritdoc cref="IEmuClientApi.CloseRom"/>
 		public static void CloseRom() => GlobalWin.ClientApi.CloseRom();
diff --git a/src/BizHawk.Client.EmuHawk/Api/Libraries/EmuClientApi.cs b/src/BizHawk.Client.EmuHawk/Api/Libraries/EmuClientApi.cs
index 9d922d9c2e..d5859c5073 100644
--- a/src/BizHawk.Client.EmuHawk/Api/Libraries/EmuClientApi.cs
+++ b/src/BizHawk.Client.EmuHawk/Api/Libraries/EmuClientApi.cs
@@ -15,7 +15,7 @@ using BizHawk.Emulation.Cores.Sega.MasterSystem;
 
 namespace BizHawk.Client.EmuHawk
 {
-	public class EmuClientApi : IEmuClientApi
+	public sealed class EmuClientApi : IEmuClientApi
 	{
 		private List<Joypad> _allJoyPads;
 
@@ -106,9 +106,7 @@ namespace BizHawk.Client.EmuHawk
 
 		public void ClearAutohold() => _mainForm.ClearHolds();
 
-		public void CloseEmulator() => _mainForm.CloseEmulator();
-
-		public void CloseEmulatorWithCode(int exitCode) => _mainForm.CloseEmulator(exitCode);
+		public void CloseEmulator(int? exitCode = null) => _mainForm.CloseEmulator(exitCode);
 
 		public void CloseRom() => _mainForm.CloseRom();
 
diff --git a/src/BizHawk.Client.EmuHawk/tools/Lua/Libraries/ClientLuaLibrary.cs b/src/BizHawk.Client.EmuHawk/tools/Lua/Libraries/ClientLuaLibrary.cs
index 7ded3fbca4..3904386107 100644
--- a/src/BizHawk.Client.EmuHawk/tools/Lua/Libraries/ClientLuaLibrary.cs
+++ b/src/BizHawk.Client.EmuHawk/tools/Lua/Libraries/ClientLuaLibrary.cs
@@ -40,7 +40,7 @@ namespace BizHawk.Client.EmuHawk
 
 		[LuaMethodExample("client.exitCode( 0 );")]
 		[LuaMethod("exitCode", "Closes the emulator and returns the provided code")]
-		public void CloseEmulatorWithCode(int exitCode) => APIs.EmuClient.CloseEmulatorWithCode(exitCode);
+		public void CloseEmulatorWithCode(int exitCode) => APIs.EmuClient.CloseEmulator(exitCode);
 
 		[LuaMethodExample("local inclibor = client.borderheight( );")]
 		[LuaMethod("borderheight", "Gets the current height in pixels of the letter/pillarbox area (top side only) around the emu display surface, excluding the gameExtraPadding you've set. This function (the whole lot of them) should be renamed or refactored since the padding areas have got more complex.")]