diff --git a/Aaru.Images/AaruFormat/DumpHardware.cs b/Aaru.Images/AaruFormat/DumpHardware.cs
index 7a117e0ae..5352ff7ae 100644
--- a/Aaru.Images/AaruFormat/DumpHardware.cs
+++ b/Aaru.Images/AaruFormat/DumpHardware.cs
@@ -143,7 +143,7 @@ public sealed partial class AaruFormat
 
         byte[] blockBytes = blockMs.ToArray();
 
-        Status res = aaruf_set_dumphw(_context, blockBytes, blockBytes.Length);
+        Status res = aaruf_set_dumphw(_context, blockBytes, (nuint)blockBytes.Length);
 
         ErrorMessage = StatusToErrorMessage(res);
 
@@ -299,7 +299,7 @@ public sealed partial class AaruFormat
     // AARU_EXPORT int32_t AARU_CALL aaruf_set_dumphw(void *context, uint8_t *data, size_t length)
     [LibraryImport("libaaruformat", EntryPoint = "aaruf_set_dumphw", SetLastError = true)]
     [UnmanagedCallConv(CallConvs = [typeof(CallConvStdcall)])]
-    private static partial Status aaruf_set_dumphw(IntPtr context, [In] byte[] data, nint length);
+    private static partial Status aaruf_set_dumphw(IntPtr context, [In] byte[] data, nuint length);
 
     // AARU_EXPORT int32_t AARU_CALL aaruf_get_dumphw(void *context, uint8_t *buffer, size_t *length)
     [LibraryImport("libaaruformat", EntryPoint = "aaruf_get_dumphw", SetLastError = true)]
diff --git a/Aaru.Images/AaruFormat/Metadata.cs b/Aaru.Images/AaruFormat/Metadata.cs
index 1dd91b495..4c0879279 100644
--- a/Aaru.Images/AaruFormat/Metadata.cs
+++ b/Aaru.Images/AaruFormat/Metadata.cs
@@ -29,7 +29,7 @@ public sealed partial class AaruFormat
 
         byte[] buffer = jsonMs.ToArray();
 
-        return aaruf_set_aaru_json_metadata(_context, buffer, (ulong)buffer.Length) == Status.Ok;
+        return aaruf_set_aaru_json_metadata(_context, buffer, (nuint)buffer.Length) == Status.Ok;
     }
 
     /// <inheritdoc />
@@ -169,7 +169,7 @@ public sealed partial class AaruFormat
     {
         get
         {
-            ulong  length = 0;
+            nuint  length = 0;
             Status res    = aaruf_get_aaru_json_metadata(_context, null, ref length);
 
             if(res != Status.Ok && res != Status.BufferTooSmall)
@@ -294,7 +294,7 @@ public sealed partial class AaruFormat
     // AARU_EXPORT int32_t AARU_CALL aaruf_set_aaru_json_metadata(void *context, uint8_t *data, size_t length)
     [LibraryImport("libaaruformat", EntryPoint = "aaruf_set_aaru_json_metadata", SetLastError = true)]
     [UnmanagedCallConv(CallConvs = [typeof(CallConvStdcall)])]
-    private static partial Status aaruf_set_aaru_json_metadata(IntPtr context, [In] byte[] data, ulong length);
+    private static partial Status aaruf_set_aaru_json_metadata(IntPtr context, [In] byte[] data, nuint length);
 
     // AARU_EXPORT int32_t AARU_CALL aaruf_set_geometry(void *context, const uint32_t cylinders, const uint32_t heads,
     // const uint32_t sectors_per_track)
@@ -372,7 +372,7 @@ public sealed partial class AaruFormat
     // AARU_EXPORT int32_t AARU_CALL aaruf_get_aaru_json_metadata(const void *context, uint8_t *buffer, size_t *length)
     [LibraryImport("libaaruformat", EntryPoint = "aaruf_get_aaru_json_metadata", SetLastError = true)]
     [UnmanagedCallConv(CallConvs = [typeof(CallConvStdcall)])]
-    private static partial Status aaruf_get_aaru_json_metadata(IntPtr context, byte[] buffer, ref ulong length);
+    private static partial Status aaruf_get_aaru_json_metadata(IntPtr context, byte[] buffer, ref nuint length);
 
     // AARU_EXPORT int32_t AARU_CALL aaruf_clear_media_sequence(void *context)
     [LibraryImport("libaaruformat", EntryPoint = "aaruf_clear_media_sequence", SetLastError = true)]
diff --git a/Aaru.Images/AaruFormat/Optical.cs b/Aaru.Images/AaruFormat/Optical.cs
index d95b615ee..ecf31bc4e 100644
--- a/Aaru.Images/AaruFormat/Optical.cs
+++ b/Aaru.Images/AaruFormat/Optical.cs
@@ -25,10 +25,9 @@ public sealed partial class AaruFormat
         {
             if(_tracks is not null) return _tracks;
 
-            byte[] buffer = null;
-            ulong  length = 0;
+            nuint length = 0;
 
-            Status res = aaruf_get_tracks(_context, buffer, ref length);
+            Status res = aaruf_get_tracks(_context, null, ref length);
 
             if(res != Status.BufferTooSmall)
             {
@@ -37,8 +36,8 @@ public sealed partial class AaruFormat
                 return null;
             }
 
-            buffer = new byte[length];
-            res    = aaruf_get_tracks(_context, buffer, ref length);
+            var buffer = new byte[length];
+            res = aaruf_get_tracks(_context, buffer, ref length);
 
             if(res != Status.Ok)
             {
@@ -197,7 +196,7 @@ public sealed partial class AaruFormat
     // AARU_EXPORT int32_t AARU_CALL aaruf_get_tracks(const void *context, uint8_t *buffer, size_t *length)
     [LibraryImport("libaaruformat", EntryPoint = "aaruf_get_tracks", SetLastError = true)]
     [UnmanagedCallConv(CallConvs = [typeof(CallConvStdcall)])]
-    private static partial Status aaruf_get_tracks(IntPtr context, byte[] buffer, ref ulong length);
+    private static partial Status aaruf_get_tracks(IntPtr context, byte[] buffer, ref nuint length);
 
     // AARU_EXPORT int32_t AARU_CALL aaruf_set_tracks(void *context, TrackEntry *tracks, const int count)
     [LibraryImport("libaaruformat", EntryPoint = "aaruf_set_tracks", SetLastError = true)]
diff --git a/Aaru.Images/AaruFormat/Write.cs b/Aaru.Images/AaruFormat/Write.cs
index 79b643bd2..7be41cc8d 100644
--- a/Aaru.Images/AaruFormat/Write.cs
+++ b/Aaru.Images/AaruFormat/Write.cs
@@ -52,7 +52,7 @@ public sealed partial class AaruFormat
     /// <inheritdoc />
     public bool WriteSectorTag(byte[] data, ulong sectorAddress, SectorTagType tag)
     {
-        Status res = aaruf_write_sector_tag(_context, sectorAddress, false, data, (ulong)data.Length, tag);
+        Status res = aaruf_write_sector_tag(_context, sectorAddress, false, data, (nuint)data.Length, tag);
 
         if(res == Status.Ok) return true;
 
@@ -179,7 +179,7 @@ public sealed partial class AaruFormat
     [UnmanagedCallConv(CallConvs = [typeof(CallConvStdcall)])]
     private static partial Status aaruf_write_sector_tag(IntPtr context, ulong sectorAddress,
                                                          [MarshalAs(UnmanagedType.I4)] bool negative, [In] byte[] data,
-                                                         ulong length, SectorTagType tag);
+                                                         nuint length, SectorTagType tag);
 
     // AARU_EXPORT void AARU_CALL *aaruf_create(const char *filepath, const uint32_t media_type, const uint32_t sector_size,
     // const uint64_t user_sectors, const uint64_t negative_sectors,