diff --git a/OpenRA.Game/OpenRA.Game.csproj b/OpenRA.Game/OpenRA.Game.csproj
index 19dacce410..a54198d055 100644
--- a/OpenRA.Game/OpenRA.Game.csproj
+++ b/OpenRA.Game/OpenRA.Game.csproj
@@ -107,11 +107,8 @@
     <Compile Include="Activities\CallFunc.cs" />
     <Compile Include="Actor.cs" />
     <Compile Include="CacheStorage.cs" />
-    <Compile Include="FileSystem\IdxEntry.cs" />
     <Compile Include="FileSystem\IPackage.cs" />
     <Compile Include="LogProxy.cs" />
-    <Compile Include="FileFormats\IdxReader.cs" />
-    <Compile Include="FileSystem\BagFile.cs" />
     <Compile Include="Map\MapGrid.cs" />
     <Compile Include="Map\MapPlayers.cs" />
     <Compile Include="MPos.cs" />
@@ -263,10 +260,7 @@
   <ItemGroup>
     <Compile Include="FileSystem\Folder.cs" />
     <Compile Include="FileSystem\InstallShieldPackage.cs" />
-    <Compile Include="FileSystem\MixFile.cs" />
-    <Compile Include="FileSystem\Pak.cs" />
     <Compile Include="FileSystem\ZipFile.cs" />
-    <Compile Include="FileSystem\BigFile.cs" />
     <Compile Include="Map\PlayerReference.cs" />
     <Compile Include="Map\TileReference.cs" />
     <Compile Include="Map\TileSet.cs" />
@@ -275,11 +269,6 @@
     <Compile Include="Manifest.cs" />
     <Compile Include="Graphics\Vertex.cs" />
     <Compile Include="FileFormats\Blast.cs" />
-    <Compile Include="FileFormats\Blowfish.cs" />
-    <Compile Include="FileFormats\BlowfishKeyProvider.cs" />
-    <Compile Include="FileFormats\CRC32.cs" />
-    <Compile Include="FileFormats\XccGlobalDatabase.cs" />
-    <Compile Include="FileFormats\XccLocalDatabase.cs" />
     <Compile Include="FileFormats\HvaReader.cs" />
     <Compile Include="FileFormats\PngLoader.cs" />
     <Compile Include="FileFormats\VxlReader.cs" />
@@ -303,7 +292,6 @@
     <Compile Include="Map\MapCache.cs" />
     <Compile Include="Map\MapPreview.cs" />
     <Compile Include="Graphics\HSLColor.cs" />
-    <Compile Include="FileSystem\PackageEntry.cs" />
     <Compile Include="CPos.cs" />
     <Compile Include="CVec.cs" />
     <Compile Include="WAngle.cs" />
diff --git a/OpenRA.Game/FileFormats/Blowfish.cs b/OpenRA.Mods.Cnc/FileFormats/Blowfish.cs
similarity index 99%
rename from OpenRA.Game/FileFormats/Blowfish.cs
rename to OpenRA.Mods.Cnc/FileFormats/Blowfish.cs
index 66f274cec0..9607fe66c2 100644
--- a/OpenRA.Game/FileFormats/Blowfish.cs
+++ b/OpenRA.Mods.Cnc/FileFormats/Blowfish.cs
@@ -9,7 +9,7 @@
  */
 #endregion
 
-namespace OpenRA.FileFormats
+namespace OpenRA.Mods.Cnc.FileFormats
 {
 	class Blowfish
 	{
diff --git a/OpenRA.Game/FileFormats/BlowfishKeyProvider.cs b/OpenRA.Mods.Cnc/FileFormats/BlowfishKeyProvider.cs
similarity index 99%
rename from OpenRA.Game/FileFormats/BlowfishKeyProvider.cs
rename to OpenRA.Mods.Cnc/FileFormats/BlowfishKeyProvider.cs
index 9ba511baf8..1806b11a19 100644
--- a/OpenRA.Game/FileFormats/BlowfishKeyProvider.cs
+++ b/OpenRA.Mods.Cnc/FileFormats/BlowfishKeyProvider.cs
@@ -12,7 +12,7 @@
 using System;
 using System.Linq;
 
-namespace OpenRA.FileFormats
+namespace OpenRA.Mods.Cnc.FileFormats
 {
 	/* TODO: Convert this direct C port into readable code. */
 
diff --git a/OpenRA.Game/FileFormats/CRC32.cs b/OpenRA.Mods.Cnc/FileFormats/CRC32.cs
similarity index 99%
rename from OpenRA.Game/FileFormats/CRC32.cs
rename to OpenRA.Mods.Cnc/FileFormats/CRC32.cs
index 3faa84f7b5..f4e954e2ba 100644
--- a/OpenRA.Game/FileFormats/CRC32.cs
+++ b/OpenRA.Mods.Cnc/FileFormats/CRC32.cs
@@ -9,7 +9,7 @@
  */
 #endregion
 
-namespace OpenRA.FileFormats
+namespace OpenRA.Mods.Cnc.FileFormats
 {
 	/// <summary>
 	/// Static class that uses a lookup table to calculates CRC32
diff --git a/OpenRA.Game/FileSystem/IdxEntry.cs b/OpenRA.Mods.Cnc/FileFormats/IdxEntry.cs
similarity index 94%
rename from OpenRA.Game/FileSystem/IdxEntry.cs
rename to OpenRA.Mods.Cnc/FileFormats/IdxEntry.cs
index bd16a402e4..0b303d6095 100644
--- a/OpenRA.Game/FileSystem/IdxEntry.cs
+++ b/OpenRA.Mods.Cnc/FileFormats/IdxEntry.cs
@@ -9,10 +9,9 @@
  */
 #endregion
 
-using System.Collections.Generic;
 using System.IO;
 
-namespace OpenRA.FileSystem
+namespace OpenRA.Mods.Cnc.FileFormats
 {
 	public class IdxEntry
 	{
diff --git a/OpenRA.Game/FileFormats/IdxReader.cs b/OpenRA.Mods.Cnc/FileFormats/IdxReader.cs
similarity index 95%
rename from OpenRA.Game/FileFormats/IdxReader.cs
rename to OpenRA.Mods.Cnc/FileFormats/IdxReader.cs
index 05c2c89acf..11349fb793 100644
--- a/OpenRA.Game/FileFormats/IdxReader.cs
+++ b/OpenRA.Mods.Cnc/FileFormats/IdxReader.cs
@@ -11,9 +11,8 @@
 
 using System.Collections.Generic;
 using System.IO;
-using OpenRA.FileSystem;
 
-namespace OpenRA.FileFormats
+namespace OpenRA.Mods.Cnc.FileFormats
 {
 	public class IdxReader
 	{
diff --git a/OpenRA.Game/FileFormats/XccGlobalDatabase.cs b/OpenRA.Mods.Cnc/FileFormats/XccGlobalDatabase.cs
similarity index 96%
rename from OpenRA.Game/FileFormats/XccGlobalDatabase.cs
rename to OpenRA.Mods.Cnc/FileFormats/XccGlobalDatabase.cs
index 6028f29ae8..0fc6442b2a 100644
--- a/OpenRA.Game/FileFormats/XccGlobalDatabase.cs
+++ b/OpenRA.Mods.Cnc/FileFormats/XccGlobalDatabase.cs
@@ -13,7 +13,7 @@ using System;
 using System.Collections.Generic;
 using System.IO;
 
-namespace OpenRA.FileFormats
+namespace OpenRA.Mods.Cnc.FileFormats
 {
 	public class XccGlobalDatabase : IDisposable
 	{
diff --git a/OpenRA.Game/FileFormats/XccLocalDatabase.cs b/OpenRA.Mods.Cnc/FileFormats/XccLocalDatabase.cs
similarity index 97%
rename from OpenRA.Game/FileFormats/XccLocalDatabase.cs
rename to OpenRA.Mods.Cnc/FileFormats/XccLocalDatabase.cs
index 802e2b349a..1459c5e5b8 100644
--- a/OpenRA.Game/FileFormats/XccLocalDatabase.cs
+++ b/OpenRA.Mods.Cnc/FileFormats/XccLocalDatabase.cs
@@ -14,7 +14,7 @@ using System.IO;
 using System.Linq;
 using System.Text;
 
-namespace OpenRA.FileFormats
+namespace OpenRA.Mods.Cnc.FileFormats
 {
 	public class XccLocalDatabase
 	{
diff --git a/OpenRA.Game/FileSystem/BagFile.cs b/OpenRA.Mods.Cnc/FileSystem/BagFile.cs
similarity index 95%
rename from OpenRA.Game/FileSystem/BagFile.cs
rename to OpenRA.Mods.Cnc/FileSystem/BagFile.cs
index 0f6e9dfe94..63199bf12c 100644
--- a/OpenRA.Game/FileSystem/BagFile.cs
+++ b/OpenRA.Mods.Cnc/FileSystem/BagFile.cs
@@ -13,10 +13,12 @@ using System;
 using System.Collections.Generic;
 using System.IO;
 using System.Text;
-using OpenRA.FileFormats;
+using OpenRA.FileSystem;
+using OpenRA.Mods.Cnc.FileFormats;
 using OpenRA.Primitives;
+using FS = OpenRA.FileSystem.FileSystem;
 
-namespace OpenRA.FileSystem
+namespace OpenRA.Mods.Cnc.FileSystem
 {
 	public class AudioBagLoader : IPackageLoader
 	{
@@ -109,7 +111,7 @@ namespace OpenRA.FileSystem
 				return index.ContainsKey(filename);
 			}
 
-			public IReadOnlyPackage OpenPackage(string filename, FileSystem context)
+			public IReadOnlyPackage OpenPackage(string filename, FS context)
 			{
 				// Not implemented
 				return null;
@@ -121,7 +123,7 @@ namespace OpenRA.FileSystem
 			}
 		}
 
-		bool IPackageLoader.TryParsePackage(Stream s, string filename, FileSystem context, out IReadOnlyPackage package)
+		bool IPackageLoader.TryParsePackage(Stream s, string filename, FS context, out IReadOnlyPackage package)
 		{
 			if (!filename.EndsWith(".bag", StringComparison.InvariantCultureIgnoreCase))
 			{
diff --git a/OpenRA.Game/FileSystem/BigFile.cs b/OpenRA.Mods.Cnc/FileSystem/BigFile.cs
similarity index 92%
rename from OpenRA.Game/FileSystem/BigFile.cs
rename to OpenRA.Mods.Cnc/FileSystem/BigFile.cs
index f5e6ac7016..cd6883e439 100644
--- a/OpenRA.Game/FileSystem/BigFile.cs
+++ b/OpenRA.Mods.Cnc/FileSystem/BigFile.cs
@@ -12,8 +12,10 @@
 using System;
 using System.Collections.Generic;
 using System.IO;
+using OpenRA.FileSystem;
+using FS = OpenRA.FileSystem.FileSystem;
 
-namespace OpenRA.FileSystem
+namespace OpenRA.Mods.Cnc.FileSystem
 {
 	public class BigLoader : IPackageLoader
 	{
@@ -97,7 +99,7 @@ namespace OpenRA.FileSystem
 				return index.ContainsKey(filename);
 			}
 
-			public IReadOnlyPackage OpenPackage(string filename, FileSystem context)
+			public IReadOnlyPackage OpenPackage(string filename, FS context)
 			{
 				// Not implemented
 				return null;
@@ -109,7 +111,7 @@ namespace OpenRA.FileSystem
 			}
 		}
 
-		bool IPackageLoader.TryParsePackage(Stream s, string filename, FileSystem context, out IReadOnlyPackage package)
+		bool IPackageLoader.TryParsePackage(Stream s, string filename, FS context, out IReadOnlyPackage package)
 		{
 			// Take a peek at the file signature
 			var signature = s.ReadASCII(4);
diff --git a/OpenRA.Game/FileSystem/MixFile.cs b/OpenRA.Mods.Cnc/FileSystem/MixFile.cs
similarity index 96%
rename from OpenRA.Game/FileSystem/MixFile.cs
rename to OpenRA.Mods.Cnc/FileSystem/MixFile.cs
index 7585b6f9ec..d8ed30bd3f 100644
--- a/OpenRA.Game/FileSystem/MixFile.cs
+++ b/OpenRA.Mods.Cnc/FileSystem/MixFile.cs
@@ -14,9 +14,12 @@ using System.Collections.Generic;
 using System.IO;
 using System.Linq;
 using OpenRA.FileFormats;
+using OpenRA.FileSystem;
+using OpenRA.Mods.Cnc.FileFormats;
 using OpenRA.Primitives;
+using FS = OpenRA.FileSystem.FileSystem;
 
-namespace OpenRA.FileSystem
+namespace OpenRA.Mods.Cnc.FileSystem
 {
 	public class MixLoader : IPackageLoader
 	{
@@ -222,7 +225,7 @@ namespace OpenRA.FileSystem
 				return index.ContainsKey(filename);
 			}
 
-			public IReadOnlyPackage OpenPackage(string filename, FileSystem context)
+			public IReadOnlyPackage OpenPackage(string filename, FS context)
 			{
 				IReadOnlyPackage package;
 				var childStream = GetStream(filename);
@@ -242,7 +245,7 @@ namespace OpenRA.FileSystem
 			}
 		}
 
-		bool IPackageLoader.TryParsePackage(Stream s, string filename, FileSystem context, out IReadOnlyPackage package)
+		bool IPackageLoader.TryParsePackage(Stream s, string filename, FS context, out IReadOnlyPackage package)
 		{
 			if (!filename.EndsWith(".mix", StringComparison.InvariantCultureIgnoreCase))
 			{
diff --git a/OpenRA.Game/FileSystem/PackageEntry.cs b/OpenRA.Mods.Cnc/FileSystem/PackageEntry.cs
similarity index 97%
rename from OpenRA.Game/FileSystem/PackageEntry.cs
rename to OpenRA.Mods.Cnc/FileSystem/PackageEntry.cs
index 27cb7e3ac7..b24240e137 100644
--- a/OpenRA.Game/FileSystem/PackageEntry.cs
+++ b/OpenRA.Mods.Cnc/FileSystem/PackageEntry.cs
@@ -13,9 +13,9 @@ using System;
 using System.Collections.Generic;
 using System.IO;
 using System.Text;
-using OpenRA.FileFormats;
+using OpenRA.Mods.Cnc.FileFormats;
 
-namespace OpenRA.FileSystem
+namespace OpenRA.Mods.Cnc.FileSystem
 {
 	public enum PackageHashType { Classic, CRC32 }
 
diff --git a/OpenRA.Game/FileSystem/Pak.cs b/OpenRA.Mods.Cnc/FileSystem/Pak.cs
similarity index 91%
rename from OpenRA.Game/FileSystem/Pak.cs
rename to OpenRA.Mods.Cnc/FileSystem/Pak.cs
index 76692c61ac..65ce6eb777 100644
--- a/OpenRA.Game/FileSystem/Pak.cs
+++ b/OpenRA.Mods.Cnc/FileSystem/Pak.cs
@@ -12,8 +12,10 @@
 using System;
 using System.Collections.Generic;
 using System.IO;
+using OpenRA.FileSystem;
+using FS = OpenRA.FileSystem.FileSystem;
 
-namespace OpenRA.FileSystem
+namespace OpenRA.Mods.Cnc.FileSystem
 {
 	public class PakFileLoader : IPackageLoader
 	{
@@ -77,7 +79,7 @@ namespace OpenRA.FileSystem
 				return index.ContainsKey(filename);
 			}
 
-			public IReadOnlyPackage OpenPackage(string filename, FileSystem context)
+			public IReadOnlyPackage OpenPackage(string filename, FS context)
 			{
 				// Not implemented
 				return null;
@@ -89,7 +91,7 @@ namespace OpenRA.FileSystem
 			}
 		}
 
-		bool IPackageLoader.TryParsePackage(Stream s, string filename, FileSystem context, out IReadOnlyPackage package)
+		bool IPackageLoader.TryParsePackage(Stream s, string filename, FS context, out IReadOnlyPackage package)
 		{
 			if (!filename.EndsWith(".pak", StringComparison.InvariantCultureIgnoreCase))
 			{
diff --git a/OpenRA.Mods.Cnc/OpenRA.Mods.Cnc.csproj b/OpenRA.Mods.Cnc/OpenRA.Mods.Cnc.csproj
index b648538d9d..fa3b968095 100644
--- a/OpenRA.Mods.Cnc/OpenRA.Mods.Cnc.csproj
+++ b/OpenRA.Mods.Cnc/OpenRA.Mods.Cnc.csproj
@@ -134,6 +134,19 @@
     <Compile Include="UtilityCommands\ImportRedAlertLegacyMapCommand.cs" />
     <Compile Include="Traits\Infiltration\InfiltrateForDecoration.cs" />
     <Compile Include="TraitsInterfaces.cs" />
+    <Compile Include="FileSystem\BagFile.cs" />
+    <Compile Include="FileSystem\BigFile.cs" />
+    <Compile Include="FileSystem\MixFile.cs" />
+    <Compile Include="FileSystem\PackageEntry.cs" />
+    <Compile Include="FileSystem\Pak.cs" />
+    <Compile Include="UtilityCommands\ListMixContentsCommand.cs" />
+    <Compile Include="FileFormats\Blowfish.cs" />
+    <Compile Include="FileFormats\BlowfishKeyProvider.cs" />
+    <Compile Include="FileFormats\IdxEntry.cs" />
+    <Compile Include="FileFormats\IdxReader.cs" />
+    <Compile Include="FileFormats\XccGlobalDatabase.cs" />
+    <Compile Include="FileFormats\XccLocalDatabase.cs" />
+    <Compile Include="FileFormats\CRC32.cs" />
   </ItemGroup>
   <ItemGroup>
     <ProjectReference Include="..\OpenRA.Game\OpenRA.Game.csproj">
diff --git a/OpenRA.Mods.Common/UtilityCommands/ListMixContentsCommand.cs b/OpenRA.Mods.Cnc/UtilityCommands/ListMixContentsCommand.cs
similarity index 92%
rename from OpenRA.Mods.Common/UtilityCommands/ListMixContentsCommand.cs
rename to OpenRA.Mods.Cnc/UtilityCommands/ListMixContentsCommand.cs
index 2821ee5c4b..875664e1e7 100644
--- a/OpenRA.Mods.Common/UtilityCommands/ListMixContentsCommand.cs
+++ b/OpenRA.Mods.Cnc/UtilityCommands/ListMixContentsCommand.cs
@@ -13,10 +13,10 @@ using System;
 using System.Collections.Generic;
 using System.IO;
 using System.Linq;
-using OpenRA.FileFormats;
-using OpenRA.FileSystem;
+using OpenRA.Mods.Cnc.FileFormats;
+using OpenRA.Mods.Cnc.FileSystem;
 
-namespace OpenRA.Mods.Common.UtilityCommands
+namespace OpenRA.Mods.Cnc.UtilityCommands
 {
 	class ListMixContents : IUtilityCommand
 	{
diff --git a/OpenRA.Mods.Common/OpenRA.Mods.Common.csproj b/OpenRA.Mods.Common/OpenRA.Mods.Common.csproj
index cdc9bc4c18..39d0d7652a 100644
--- a/OpenRA.Mods.Common/OpenRA.Mods.Common.csproj
+++ b/OpenRA.Mods.Common/OpenRA.Mods.Common.csproj
@@ -760,7 +760,6 @@
     <Compile Include="Widgets\Logic\Installation\ModContentDiscTooltipLogic.cs" />
     <Compile Include="Widgets\Logic\Installation\InstallFromDiscLogic.cs" />
     <Compile Include="Widgets\Logic\Installation\ModContentPromptLogic.cs" />
-    <Compile Include="UtilityCommands\ListMixContentsCommand.cs" />
     <Compile Include="UtilityCommands\ListMSCabContentsCommand.cs" />
     <Compile Include="FileFormats\MSCabCompression.cs" />
     <Compile Include="Traits\World\ScriptLobbyDropdown.cs" />