Hacker News Reader

Comment by michelpp | Hacker News Reader

This looks very cool and it's nice to see some finicky details like PG_GETARG abstracted away.

Are there any plans to make pgzx a Trusted Language so that Zig functions could be written with CREATE FUNCTION? Rust recently achieved this milestone and AWS RDS now supports PL/Rust.

Being a trusted language would mean it could be used to create Trusted Language Extensions (TLEs) and could be installed on cloud hosted databases without filesystem access.

View on HN

No TLE support is a not a goal. Languages/extensions in Postgres should only be marked as trusted if you can guarantee that they do not access Postgres internals or even the file filesystem. With Zig and in pgzx in particular we can not guarantee this to be the case.

With pgzx we provide you a number of utilities on top of the C API. But depending on the extension you are working on you might heavily use the Postgres internals and their C APIs as is.

Postgres has support for a number of languages. Some having their own strenghts or weaknesses. One strength of Zig is its closeness to C, while providing a many quality of live improvements over C (optional types instead of null pointer, generic data structures, ...). This makes it a formidable choice for extensions that want to integrate deeply with the Postgres internals.

If I suddenly had unlimited resources and attention, I'd really like to provide infrastructure to write trusted functions by running them via a webassembly runtime, with a small injected safe surface for accessing postgres functionality. That'd make it a lot easier to write trusted PLs in a variety of languages. Still probably needs a bit of per-language sugar on top, but a lot less than doing it from scratch.

Edit: Minor grammar fix

Hehe :)

I also have WASM in mind when thinking about future TLE support :)

I don't know much about it, but I think this has been tried?

https://dylibso.com/blog/pg-extism/

Looking at the repo though it looks like it hasn't been updated in a while.

we're actually working on a new version of this, which _does_ support TLE! if you're interested, please join https://extism.org/discord and we can get you a preview.

Oh wow, that is really cool.

Oracle, IBM and Microsoft have been doing that for decades with JVM, CLR and TIMI, yet another use case where Webassembly is a follower.

It would be amazing if we could could use Zig for TLEs, and we'll look into it, but I worry it might not be possible because Zig can't guarantee memory safety in the same way that Rust can.

If you build it, they'll come. The only limit is yourself!

I understood that reference, zombo :)

Y'all have built something cool. I'm excited to see where it goes from here.

If there's anything the pgrx team can do to help, just let us know.

Reply on news.ycombinator.com