What new in Convex November 2025 - Zod4 - Validators - Codegen - React Query

Despite being less than a dozen people

or so, the engineering team at Convex

has been absolutely ripping through new

features lately, up to the point where

it's actually really quite hard to keep

up with it all. So today, I thought I

would share a few of my favorite updates

in rapid fire fashion so you can get

back to pushing your AI model around.

All right, so first up, there's been a

bunch of work lately to add a few more

helper functions to the convex

validators. So before this latest

update, which is v 1.29, 29. You had to

manually redefine validators whenever

you needed slight variations like you

can see here. Or a way that I often do

it is I extract out common fields into

an object that you then spread into

other validators. Um I've done this many

times on various projects. But now I

don't need to because we can reuse and

transform these validators with these

handydandy pick and omit functions. And

then there's also this new

partial.parial partial function that

allows us to make a specific validator

entirely optional. And you can use this

extend to extend an existing validator

without doing that spread trick. Very

cool, super useful.

But that's not all for validators. So,

previously you would have to manually

write out the pageionation result

validator. Something like this. Kind of

ugly and annoying if you ask me. Well,

now you don't need to because you can

use this built-in pageionating result

validator helper. Much nicer. Well, by

the way, if you like this kind of

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Oh, one last thing from validators, we

have this new nullable helper. So if you

are like me and you have written this

kind of thing frequently where your code

you do a union to produce a nullable

string well you don't need to do it

anymore because you can now use this

nullable on a string and it's now a

nullable string.

So this is an interesting one. So

previously u generated files in the

/convex generated folder would be added

with a td.ts ts and ajs file. But now

you can configure it so that you can

either get it to generate uh as as it

was before or you can get it generate

with a ts extension without those.js and

DTS files. This is really nice for IDE

tooling um and it keeps things nice and

consistent with components uh which

always used thet extension anyway.

So, this is one I wanted to cover, not

just because I personally worked on it,

but because I think it's actually really

cool. Um, if you're using our React

query library, you might have noticed a

little annoyance where you had to pass

in an empty object even if the function

didn't actually require any arcs. And I

knew there must be a way that this to

remove this requirement because uh our

just regular React use query hook

doesn't require it. Well, as of the next

version of React Query, Convex React

Query, you no longer have to provide it

just like with use query. And the same

goes for situations where you supply an

arc that doesn't actually need to be

there. So, um, for example, in this case

here, we're providing something, but the

function list doesn't take a something.

So, what this would do is would create a

runtime error in your validator because

the function would run and it would say,

"Ah, you've provided something that

doesn't need to be there." But

Typescript should catch us here.

Previously, our React query

implementation didn't uh error here, but

it now does. Much nicer.

All right, so this one definitely

deserves special mention because it was

a long time coming and honestly more

work than we expected. For those of you

that weren't aware, Zod released version

4 um a fair time ago, but only recently

became stable. and it came with a bunch

of pretty significant changes, but some

awesome new features. The ComX team knew

that we needed to update the the helper

support, but we thought it would be

relatively straightforward, but it ended

up turning into multiple PRs and this

massive 180 commit monster that took

weeks to get right. One of the main

challenges that we wanted to support

both Zod 3 and Zod 4 at the same time

and give everybody a smooth migration

path. And so this basically meant

implementing everything twice, not to

mention all the extra support that we

needed around Zod's four schemas, etc.

So what did we end up with? Well, first

up, the helpers can now work with both

Zod 3 and Zod 4 out of the box. If

you're using Zod 3, you can import from

convex helpers/server/zod

3. And if you're using ZOD 4, you can

import from convexhelpers/server/zod

4. But the really cool new thing is zod

4 codecs. One really nice thing we can

do with codecs is it allows us to

convert from one type to another. So for

example, here we have a codec that

allows us to convert from an ISO date

string and a to a JavaScript date object

and back again. Then in our convex code,

we can use it like so. Notice here how

the uh date argument is automatically

decoded into a JavaScript date object

which we can then work with as we

normally would. And then when we return

it, the codec automatically encodes it

back into a string. Then on the front

end, we can use that codec again to

encode it back to a date. Super clean. I

do want to just give a quick massive

shout out to Karen Single and Nate Dunn

who were instrumental with helping with

this uh upgrade from Zod 3 to Zod 4. So,

thanks guys. All right. Well, there you

have it. Just a quick rapid fire tour

through some of the latest convex that I

think are the most important ones, but

there's so much more that I didn't

cover. Like I said, the team is

absolutely ripping through new features

at the moment and it's just genuinely

hard to keep up. So, if there's anything

I covered here today that you'd like me

to dive into a bit deeper, then don't

forget to drop me a comment down below.

I love reading them and I try and

respond to most of them. Anyway, that's

it for me for today. Until next time,

thanks for watching. Cheerio.