Ask HN: Zero-downtime migration from MongoBD to PostgresSQL

Hey,

we are looking for an efficient way to migrate away from MongoDB to Postgres. Were hosted on Mongo Cloud ATM but i dont think theyll provide us a solution.

Key thing is were running a system which can not go down, and looking online i could not find anything that seems reliable and would help us to achieve that. Developing an in house solution for a one-off job also seems to be not the best one.

Maybe someone has experience regarding that, and could at least point in a good way? Would be really helpful. Thanks!