diff --git a/src/LightningDB.Tests/TransactionTests.cs b/src/LightningDB.Tests/TransactionTests.cs
index 5fde364..c66fc72 100644
--- a/src/LightningDB.Tests/TransactionTests.cs
+++ b/src/LightningDB.Tests/TransactionTests.cs
@@ -294,7 +294,7 @@ public void can_get_transaction_id()
 
         env.RunTransactionScenario((tx, _) =>
         {
-            tx.Id.ShouldBeGreaterThan(0);
+            tx.Id.ShouldBeGreaterThan((nuint)0);
         });
     }
 
diff --git a/src/LightningDB/LightningCursor.cs b/src/LightningDB/LightningCursor.cs
index 20cd388..6f8f8d6 100644
--- a/src/LightningDB/LightningCursor.cs
+++ b/src/LightningDB/LightningCursor.cs
@@ -521,9 +521,11 @@ public MDBResultCode Renew(LightningTransaction txn)
     /// </summary>
     /// <param name="value">Output parameter where the duplicate count will be stored.</param>
     /// <returns>Returns <see cref="MDBResultCode"/></returns>
-    public MDBResultCode Count(out int value)
+    public MDBResultCode Count(out long value)
     {
-        return mdb_cursor_count(_handle, out value);
+        var result = mdb_cursor_count(_handle, out var count);
+        value = checked((long)count);
+        return result;
     }
 
     private bool ShouldCloseCursor()
diff --git a/src/LightningDB/LightningTransaction.cs b/src/LightningDB/LightningTransaction.cs
index 20afd6e..09fb122 100644
--- a/src/LightningDB/LightningTransaction.cs
+++ b/src/LightningDB/LightningTransaction.cs
@@ -422,7 +422,7 @@ public Stats GetStats(LightningDatabase db)
     /// <summary>
     /// Gets the transaction ID.
     /// </summary>
-    public int Id => mdb_txn_id(_handle);
+    public nuint Id => mdb_txn_id(_handle);
 
     /// <summary>
     /// Compares two data items according to the database's key comparison function.
diff --git a/src/LightningDB/Native/Lmdb.cs b/src/LightningDB/Native/Lmdb.cs
index 5278a3b..50d5d5a 100644
--- a/src/LightningDB/Native/Lmdb.cs
+++ b/src/LightningDB/Native/Lmdb.cs
@@ -229,7 +229,7 @@ public static partial class Lmdb
     /// <returns>The transaction ID</returns>
     [LibraryImport(MDB_DLL_NAME)]
     [UnmanagedCallConv(CallConvs = [typeof(CallConvCdecl)])]
-    public static partial int mdb_txn_id(nint txn);
+    public static partial nuint mdb_txn_id(nint txn);
 
     /// <summary>
     /// Commits all the operations of a transaction into the database.
@@ -388,7 +388,7 @@ public static partial class Lmdb
     /// <returns>A result code indicating success or failure</returns>
     [LibraryImport(MDB_DLL_NAME)]
     [UnmanagedCallConv(CallConvs = [typeof(CallConvCdecl)])]
-    public static partial MDBResultCode mdb_cursor_count(nint cursor, out int countp);
+    public static partial MDBResultCode mdb_cursor_count(nint cursor, out nuint countp);
 
     /// <summary>
     /// Stores key/data pairs in a database.
@@ -872,7 +872,7 @@ internal static MDBResultCode mdb_env_open(nint env, string path, EnvironmentOpe
         /// <param name="txn">A transaction handle</param>
         /// <returns>The transaction ID</returns>
         [DllImport(MDB_DLL_NAME, CallingConvention = CallingConvention.Cdecl)]
-        public static extern int mdb_txn_id(nint txn);
+        public static extern nuint mdb_txn_id(nint txn);
 
         /// <summary>
         /// Commits all the operations of a transaction into the database.
@@ -1040,7 +1040,7 @@ public static MDBResultCode mdb_env_copy2(nint env, string path, EnvironmentCopy
         /// <param name="countp">Address where the count will be stored</param>
         /// <returns>A result code indicating success or failure</returns>
         [DllImport(MDB_DLL_NAME, CallingConvention = CallingConvention.Cdecl)]
-        public static extern MDBResultCode mdb_cursor_count(nint cursor, out int countp);
+        public static extern MDBResultCode mdb_cursor_count(nint cursor, out nuint countp);
 
         /// <summary>
         /// Stores key/data pairs in a database.