I often go down rabbit holes like this, trying to collapse and simplify the application stack.
But inevitably, as an application grows in complexity, you start to realize _why_ there's a stack, rather than just a single technology to rule them all. Trying to cram everything into Postgres (or lambdas, or S3, or firebase, or whatever other tech you're trying to consolidate on) starts to get really uncomfortable.
That said, sometimes stretching your existing tech is better than adding another layer to the stack. E.g. using postgres as a message queue has worked very well for me, and is much easier to maintain than having a totally separate message queue.
I think the main takeaway here is that postgres is wildly extensible as databases go, which makes it a really fun technology to build on.
But inevitably, as an application grows in complexity, you start to realize _why_ there's a stack, rather than just a single technology to rule them all. Trying to cram everything into Postgres (or lambdas, or S3, or firebase, or whatever other tech you're trying to consolidate on) starts to get really uncomfortable.
That said, sometimes stretching your existing tech is better than adding another layer to the stack. E.g. using postgres as a message queue has worked very well for me, and is much easier to maintain than having a totally separate message queue.
I think the main takeaway here is that postgres is wildly extensible as databases go, which makes it a really fun technology to build on.