Use an interface instead of method reflection to call the API

src/main/java/dan200/computercraft/ComputerCraft.java

@@ -422,11 +422,6 @@ public void onServerStopped( FMLServerStoppedEvent event )
         }
     }
 
-    public static String getVersion()
-    {
-        return "${version}";
-    }
-
     public static boolean isClient()
     {
         return proxy.isClient();
@@ -665,15 +660,6 @@ public static IPeripheral getPeripheralAt( World world, BlockPos pos, EnumFacing
         return null;
     }
 
-    public static int getDefaultBundledRedstoneOutput( World world, BlockPos pos, EnumFacing side )
-    {
-        if( WorldUtil.isBlockInWorld( world, pos ) )
-        {
-            return DefaultBundledRedstoneProvider.getDefaultBundledRedstoneOutput( world, pos, side );
-        }
-        return -1;
-    }
-
     public static int getBundledRedstoneOutput( World world, BlockPos pos, EnumFacing side )
     {
         int y = pos.getY();
@@ -766,11 +752,6 @@ public static Iterable<IPocketUpgrade> getVanillaPocketUpgrades() {
         return upgrades;
     }
 
-    public static IPacketNetwork getWirelessNetwork()
-    {
-        return WirelessNetwork.getUniversal();
-    }
-
     public static int createUniqueNumberedSaveDir( World world, String parentSubPath )
     {
         return IDAssigner.getNextIDFromDirectory(new File(getWorldDir(world), parentSubPath));

src/main/java/dan200/computercraft/ComputerCraftAPIImpl.java

@@ -0,0 +1,109 @@
+package dan200.computercraft;
+
+import dan200.computercraft.api.ComputerCraftAPI.IComputerCraftAPI;
+import dan200.computercraft.api.filesystem.IMount;
+import dan200.computercraft.api.filesystem.IWritableMount;
+import dan200.computercraft.api.media.IMediaProvider;
+import dan200.computercraft.api.network.IPacketNetwork;
+import dan200.computercraft.api.peripheral.IPeripheralProvider;
+import dan200.computercraft.api.permissions.ITurtlePermissionProvider;
+import dan200.computercraft.api.pocket.IPocketUpgrade;
+import dan200.computercraft.api.redstone.IBundledRedstoneProvider;
+import dan200.computercraft.api.turtle.ITurtleUpgrade;
+import dan200.computercraft.shared.common.DefaultBundledRedstoneProvider;
+import dan200.computercraft.shared.peripheral.modem.WirelessNetwork;
+import dan200.computercraft.shared.util.WorldUtil;
+import net.minecraft.util.EnumFacing;
+import net.minecraft.util.math.BlockPos;
+import net.minecraft.world.World;
+
+import javax.annotation.Nonnull;
+import javax.annotation.Nullable;
+
+public final class ComputerCraftAPIImpl implements IComputerCraftAPI
+{
+    public static final IComputerCraftAPI INSTANCE = new ComputerCraftAPIImpl();
+
+    private ComputerCraftAPIImpl()
+    {
+    }
+
+    @Nonnull
+    @Override
+    public String getInstalledVersion()
+    {
+        return "${version}";
+    }
+
+    @Override
+    public int createUniqueNumberedSaveDir( @Nonnull World world, @Nonnull String parentSubPath )
+    {
+        return ComputerCraft.createUniqueNumberedSaveDir( world, parentSubPath );
+    }
+
+    @Nullable
+    @Override
+    public IWritableMount createSaveDirMount( @Nonnull World world, @Nonnull String subPath, long capacity )
+    {
+        return ComputerCraft.createSaveDirMount( world, subPath, capacity );
+    }
+
+    @Nullable
+    @Override
+    public IMount createResourceMount( @Nonnull Class<?> modClass, @Nonnull String domain, @Nonnull String subPath )
+    {
+        return ComputerCraft.createResourceMount( modClass, domain, subPath );
+    }
+
+    @Override
+    public void registerPeripheralProvider( @Nonnull IPeripheralProvider handler )
+    {
+        ComputerCraft.registerPeripheralProvider( handler );
+    }
+
+    @Override
+    public void registerTurtleUpgrade( @Nonnull ITurtleUpgrade upgrade )
+    {
+        ComputerCraft.registerTurtleUpgrade( upgrade );
+    }
+
+    @Override
+    public void registerBundledRedstoneProvider( @Nonnull IBundledRedstoneProvider handler )
+    {
+        ComputerCraft.registerBundledRedstoneProvider( handler );
+    }
+
+    @Override
+    public int getBundledRedstoneOutput( @Nonnull World world, @Nonnull BlockPos pos, @Nonnull EnumFacing side )
+    {
+        if( WorldUtil.isBlockInWorld( world, pos ) )
+        {
+            return DefaultBundledRedstoneProvider.getDefaultBundledRedstoneOutput( world, pos, side );
+        }
+        return -1;
+    }
+
+    @Override
+    public void registerMediaProvider( @Nonnull IMediaProvider handler )
+    {
+        ComputerCraft.registerMediaProvider( handler );
+    }
+
+    @Override
+    public void registerPermissionProvider( @Nonnull ITurtlePermissionProvider handler )
+    {
+        ComputerCraft.registerPermissionProvider( handler );
+    }
+
+    @Override
+    public void registerPocketUpgrade( @Nonnull IPocketUpgrade upgrade )
+    {
+        ComputerCraft.registerPocketUpgrade( upgrade );
+    }
+
+    @Override
+    public IPacketNetwork getWirelessNetwork()
+    {
+        return WirelessNetwork.getUniversal();
+    }
+}