diff --git a/mdbx.h b/mdbx.h
index d01bd4f3..867ec5e5 100644
--- a/mdbx.h
+++ b/mdbx.h
@@ -1631,6 +1631,167 @@ LIBMDBX_API int mdbx_is_dirty(const MDBX_txn *txn, const void *ptr);
 LIBMDBX_API int mdbx_dbi_sequence(MDBX_txn *txn, MDBX_dbi dbi, uint64_t *result,
                                   uint64_t increment);
 
+/*----------------------------------------------------------------------------*/
+/* attribute support functions for Nexenta */
+typedef uint64_t mdbx_attr_t;
+
+	/** @brief Store by cursor with attribute.
+	 *
+	 * This function stores key/data pairs into the database.
+	 * The cursor is positioned at the new item, or on failure usually near it.
+	 * @note Internally based on #MDBX_RESERVE feature, therefore doesn't support #MDBX_DUPSORT.
+	 * @note Earlier documentation incorrectly said errors would leave the
+	 * state of the cursor unchanged.
+	 * @param[in] cursor A cursor handle returned by #mdb_cursor_open()
+	 * @param[in] key The key operated on.
+	 * @param[in] data The data operated on.
+	 * @param[in] attr The attribute.
+	 * @param[in] flags Options for this operation. This parameter
+	 * must be set to 0 or one of the values described here.
+	 * <ul>
+	 *	<li>#MDBX_CURRENT - replace the item at the current cursor position.
+	 *		The \b key parameter must still be provided, and must match it.
+	 *		This is intended to be used when the
+	 *		new data is the same size as the old. Otherwise it will simply
+	 *		perform a delete of the old record followed by an insert.
+	 *	<li>#MDBX_NOOVERWRITE - enter the new key/data pair only if the key
+	 *		does not already appear in the database. The function will return
+	 *		#MDBX_KEYEXIST if the key already appears in the database.
+	 *	<li>#MDBX_RESERVE - reserve space for data of the given size, but
+	 *		don't copy the given data. Instead, return a pointer to the
+	 *		reserved space, which the caller can fill in later. This saves
+	 *		an extra memcpy if the data is being generated later.
+	 *	<li>#MDBX_APPEND - append the given key/data pair to the end of the
+	 *		database. No key comparisons are performed. This option allows
+	 *		fast bulk loading when keys are already known to be in the
+	 *		correct order. Loading unsorted keys with this flag will cause
+	 *		data corruption.
+	 * </ul>
+	 * @return A non-zero error value on failure and 0 on success. Some possible
+	 * errors are:
+	 * <ul>
+	 *	<li>#MDBX_MAP_FULL - the database is full, see #mdb_env_set_mapsize().
+	 *	<li>#MDBX_TXN_FULL - the transaction has too many dirty pages.
+	 *	<li>EACCES - an attempt was made to write in a read-only transaction.
+	 *	<li>EINVAL - an invalid parameter was specified.
+	 * </ul>
+	 */
+int mdbx_cursor_put_attr(MDBX_cursor *cursor, MDBX_val *key, MDBX_val *data,
+				mdbx_attr_t attr, unsigned flags);
+
+	/** @brief Store items and attributes into a database.
+	 *
+	 * This function stores key/data pairs in the database. The default behavior
+	 * is to enter the new key/data pair, replacing any previously existing key
+	 * if duplicates are disallowed.
+	 * @note Internally based on #MDBX_RESERVE feature, therefore doesn't support #MDBX_DUPSORT.
+	 * @param[in] txn A transaction handle returned by #mdb_txn_begin()
+	 * @param[in] dbi A database handle returned by #mdb_dbi_open()
+	 * @param[in] key The key to store in the database
+	 * @param[in] attr The attribute to store in the database
+	 * @param[in,out] data The data to store
+	 * @param[in] flags Special options for this operation. This parameter
+	 * must be set to 0 or by bitwise OR'ing together one or more of the
+	 * values described here.
+	 * <ul>
+	 *	<li>#MDBX_NOOVERWRITE - enter the new key/data pair only if the key
+	 *		does not already appear in the database. The function will return
+	 *		#MDBX_KEYEXIST if the key already appears in the database. The \b data
+	 *		parameter will be set to point to the existing item.
+	 *	<li>#MDBX_RESERVE - reserve space for data of the given size, but
+	 *		don't copy the given data. Instead, return a pointer to the
+	 *		reserved space, which the caller can fill in later - before
+	 *		the next update operation or the transaction ends. This saves
+	 *		an extra memcpy if the data is being generated later.
+	 *		LMDB does nothing else with this memory, the caller is expected
+	 *		to modify all of the space requested.
+	 *	<li>#MDBX_APPEND - append the given key/data pair to the end of the
+	 *		database. This option allows fast bulk loading when keys are
+	 *		already known to be in the correct order. Loading unsorted keys
+	 *		with this flag will cause a #MDBX_KEYEXIST error.
+	 * </ul>
+	 * @return A non-zero error value on failure and 0 on success. Some possible
+	 * errors are:
+	 * <ul>
+	 *	<li>#MDBX_MAP_FULL - the database is full, see #mdb_env_set_mapsize().
+	 *	<li>#MDBX_TXN_FULL - the transaction has too many dirty pages.
+	 *	<li>EACCES - an attempt was made to write in a read-only transaction.
+	 *	<li>EINVAL - an invalid parameter was specified.
+	 * </ul>
+	 */
+int mdbx_put_attr(MDBX_txn *txn, MDBX_dbi dbi, MDBX_val *key, MDBX_val *data,
+				mdbx_attr_t attr, unsigned flags);
+
+	/** @brief Set items attribute from a database.
+	 *
+	 * This function stores key/data pairs attribute to the database.
+	 * @note Internally based on #MDBX_RESERVE feature, therefore doesn't support #MDBX_DUPSORT.
+	 *
+	 * @param[in] txn A transaction handle returned by #mdb_txn_begin()
+	 * @param[in] dbi A database handle returned by #mdb_dbi_open()
+	 * @param[in] key The key to search for in the database
+	 * @param[in] data The data to be stored or NULL to save previous value.
+	 * @param[in] attr The attribute to be stored
+	 * @return A non-zero error value on failure and 0 on success. Some possible
+	 * errors are:
+	 * <ul>
+	 *	<li>#MDBX_NOTFOUND - the key-value pair was not in the database.
+	 *	<li>EINVAL - an invalid parameter was specified.
+	 * </ul>
+	 */
+int mdbx_set_attr(MDBX_txn *txn, MDBX_dbi dbi, MDBX_val *key, MDBX_val *data,
+				mdbx_attr_t attr);
+
+	/** @brief Get items attribute from a database cursor.
+	 *
+	 * This function retrieves key/data pairs attribute from the database.
+	 * The attribute of the specified key-value pair is returned in
+	 * uint64_t to which \b attrptr refers.
+	 * If the database supports duplicate keys (#MDBX_DUPSORT) then both
+	 * key and data parameters are required, otherwise data could be NULL.
+	 *
+	 * @note Values returned from the database are valid only until a
+	 * subsequent update operation, or the end of the transaction.
+	 * @param[in] mc A database cursor pointing at the node
+	 * @param[in] key The key to search for in the database
+	 * @param[in,out] data The data for #MDBX_DUPSORT databases
+	 * @param[out] attrptr The pointer to the result
+	 * @param[in] op A cursor operation #MDBX_cursor_op
+	 * @return A non-zero error value on failure and 0 on success. Some possible
+	 * errors are:
+	 * <ul>
+	 *	<li>#MDBX_NOTFOUND - the key-value pair was not in the database.
+	 *	<li>EINVAL - an invalid parameter was specified.
+	 * </ul>
+	 */
+int mdbx_cursor_get_attr(MDBX_cursor *mc, MDBX_val *key, MDBX_val *data,
+				mdbx_attr_t *attrptr, MDBX_cursor_op op);
+
+	/** @brief Get items attribute from a database.
+	 *
+	 * This function retrieves key/data pairs attribute from the database.
+	 * The attribute of the specified key-value pair is returned in
+	 * uint64_t to which \b attrptr refers.
+	 * If the database supports duplicate keys (#MDBX_DUPSORT) then both
+	 * key and data parameters are required, otherwise data is ignored.
+	 *
+	 * @note Values returned from the database are valid only until a
+	 * subsequent update operation, or the end of the transaction.
+	 * @param[in] txn A transaction handle returned by #mdb_txn_begin()
+	 * @param[in] dbi A database handle returned by #mdb_dbi_open()
+	 * @param[in] key The key to search for in the database
+	 * @param[in] data The data for #MDBX_DUPSORT databases
+	 * @param[out] attrptr The pointer to the result
+	 * @return A non-zero error value on failure and 0 on success. Some possible
+	 * errors are:
+	 * <ul>
+	 *	<li>#MDBX_NOTFOUND - the key-value pair was not in the database.
+	 *	<li>EINVAL - an invalid parameter was specified.
+	 * </ul>
+	 */
+int mdbx_get_attr(MDBX_txn *txn, MDBX_dbi dbi, MDBX_val *key, MDBX_val *data,
+				mdbx_attr_t *attrptr);
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/src/mdbx.c b/src/mdbx.c
index ae1a71ff..57ebe42d 100644
--- a/src/mdbx.c
+++ b/src/mdbx.c
@@ -11097,3 +11097,141 @@ int mdbx_dbi_sequence(MDBX_txn *txn, MDBX_dbi dbi, uint64_t *result,
 
   return MDBX_SUCCESS;
 }
+
+/*----------------------------------------------------------------------------*/
+/* attribute support functions for Nexenta */
+
+static __inline int
+mdbx_attr_peek(MDBX_val *data, mdbx_attr_t *attrptr)
+{
+	if (unlikely(data->iov_len < sizeof(mdbx_attr_t)))
+		return MDBX_INCOMPATIBLE;
+
+	if (likely(attrptr != NULL))
+		*attrptr = *(mdbx_attr_t*) data->iov_base;
+	data->iov_len -= sizeof(mdbx_attr_t);
+	data->iov_base = likely(data->iov_len > 0)
+		? ((mdbx_attr_t*) data->iov_base) + 1 : NULL;
+
+	return MDBX_SUCCESS;
+}
+
+static __inline int
+mdbx_attr_poke(MDBX_val *reserved, MDBX_val *data, mdbx_attr_t attr, unsigned flags)
+{
+	mdbx_attr_t *space = reserved->iov_base;
+	if (flags & MDBX_RESERVE) {
+		if (likely(data != NULL)) {
+			data->iov_base = data->iov_len ? space + 1 : NULL;
+		}
+	} else {
+		*space = attr;
+		if (likely(data != NULL)) {
+			memcpy(space + 1, data->iov_base, data->iov_len );
+		}
+	}
+
+	return MDBX_SUCCESS;
+}
+
+int
+mdbx_cursor_get_attr(MDBX_cursor *mc, MDBX_val *key, MDBX_val *data,
+	mdbx_attr_t *attrptr, MDBX_cursor_op op)
+{
+	int rc = mdbx_cursor_get(mc, key, data, op);
+	if (unlikely(rc != MDBX_SUCCESS))
+		return rc;
+
+	return mdbx_attr_peek(data, attrptr);
+}
+
+int
+mdbx_get_attr(MDBX_txn *txn, MDBX_dbi dbi,
+	MDBX_val *key, MDBX_val *data, uint64_t *attrptr)
+{
+	int rc = mdbx_get(txn, dbi, key, data);
+	if (unlikely(rc != MDBX_SUCCESS))
+		return rc;
+
+	return mdbx_attr_peek(data, attrptr);
+}
+
+int
+mdbx_put_attr(MDBX_txn *txn, MDBX_dbi dbi,
+	MDBX_val *key, MDBX_val *data, mdbx_attr_t attr, unsigned flags)
+{
+	MDBX_val reserve = {
+		.iov_base = NULL,
+		.iov_len = (data ? data->iov_len : 0) + sizeof(mdbx_attr_t)
+	};
+
+	int rc = mdbx_put(txn, dbi, key, &reserve, flags | MDBX_RESERVE);
+	if (unlikely(rc != MDBX_SUCCESS))
+		return rc;
+
+	return mdbx_attr_poke(&reserve, data, attr, flags);
+}
+
+int mdbx_cursor_put_attr(MDBX_cursor *cursor, MDBX_val *key, MDBX_val *data,
+	mdbx_attr_t attr, unsigned flags)
+{
+	MDBX_val reserve = {
+		.iov_base = NULL,
+		.iov_len = (data ? data->iov_len : 0) + sizeof(mdbx_attr_t)
+	};
+
+	int rc = mdbx_cursor_put(cursor, key, &reserve, flags | MDBX_RESERVE);
+	if (unlikely(rc != MDBX_SUCCESS))
+		return rc;
+
+	return mdbx_attr_poke(&reserve, data, attr, flags);
+}
+
+int mdbx_set_attr(MDBX_txn *txn, MDBX_dbi dbi,
+	MDBX_val *key, MDBX_val *data, mdbx_attr_t attr)
+{
+	MDBX_cursor      mc;
+	MDBX_xcursor     mx;
+	MDBX_val         old_data;
+	mdbx_attr_t		old_attr;
+	int             rc;
+
+	if (unlikely(!key || !txn))
+		return EINVAL;
+
+	if (unlikely(txn->mt_signature != MDBX_MT_SIGNATURE))
+		return MDBX_VERSION_MISMATCH;
+
+	if (unlikely(!TXN_DBI_EXIST(txn, dbi, DB_USRVALID)))
+		return EINVAL;
+
+	if (unlikely(txn->mt_flags & (MDBX_TXN_RDONLY|MDBX_TXN_BLOCKED)))
+		return (txn->mt_flags & MDBX_TXN_RDONLY) ? EACCES : MDBX_BAD_TXN;
+
+	mdbx_cursor_init(&mc, txn, dbi, &mx);
+	rc = mdbx_cursor_set(&mc, key, &old_data, MDBX_SET, NULL);
+	if (unlikely(rc != MDBX_SUCCESS)) {
+		if (rc == MDBX_NOTFOUND && data) {
+			mc.mc_next = txn->mt_cursors[dbi];
+			txn->mt_cursors[dbi] = &mc;
+			rc = mdbx_cursor_put_attr(&mc, key, data, attr, 0);
+			txn->mt_cursors[dbi] = mc.mc_next;
+		}
+		return rc;
+	}
+
+	rc = mdbx_attr_peek(&old_data, &old_attr);
+	if (unlikely(rc != MDBX_SUCCESS))
+		return rc;
+
+	if (old_attr == attr && (!data ||
+			(data->iov_len == old_data.iov_len
+				&& memcpy(data->iov_base, old_data.iov_base, old_data.iov_len) == 0)))
+		return MDBX_SUCCESS;
+
+	mc.mc_next = txn->mt_cursors[dbi];
+	txn->mt_cursors[dbi] = &mc;
+	rc = mdbx_cursor_put_attr(&mc, key, data ? data : &old_data, attr, MDBX_CURRENT);
+	txn->mt_cursors[dbi] = mc.mc_next;
+	return rc;
+}