I aggree - I'm not understanding the value of the project either if you look at the example here https://github.com/microsoft/pg_durable/blob/main/examples/i...

It's an interesting technical achievement I guess, but it's very bizarre to try and read this

    SELECT df.start(
        @> (
            ($$SELECT ... FROM demo.invoices WHERE status = 'pending'$$ |=> 'inv')
            ~> df.if_rows('inv',
                $$UPDATE ... SET status = 'processing'$$
                ~> (df.http(...) |=> 'resp')
                ~> df.if($$SELECT $r.ok$$,
                    -- classify, branch, wait for signal ...
                ),
                df.sleep(5)
            )
        ),
        'invoice-approval-pipeline'
    );

(pg_durable committer here)

The provider is an extensibility point. We just shipped the simplest version of it. Happy to take contribs if someone sends a pgmq based provider!

It’s sometimes convenient if database is the only ”stateful” component in architecture.

Also if all the "state" is in one database, then you have better chance of getting consistent backups.

You can have well-integrated applicative workflows (eg: progress report on a permalink in your front end app), app-restart-proof resumable workflows, and it avoids adding an extra piece of infrastructure.

We use Postgres for that on https://transport.data.gouv.fr (Elixir app which does a fair bit of processing), and it helps.

Not familiar yet with pg_durable though, but I have used or implemented similar solutions and can relate.