In Amazon Aurora, you can use fast DDL to run an ALTER TABLE operation in place, nearly instantaneously. The operation completes without requiring the table to be copied and without having a material impact on other DML statements. Because the operation doesn’t consume temporary storage for a table copy, it makes DDL statements practical even for large tables on small instance classes.

Important

Currently, Aurora lab mode must be enabled to use fast DDL for Aurora MySQL. We don’t [recommend] using fast DDL for production DB clusters. For information about enabling Aurora lab mode, see Amazon Aurora MySQL lab mode.

Source: Altering tables in Amazon Aurora using fast DDL - Amazon Aurora

Definitely interesting, but I guess I don’t get the point if it’s not production-ready.