Fabian Hiller (@FabianHiller) / X

Fabian Hiller

3,196 posts

Fabian Hiller

@FabianHiller

TypeScript expert w/ 300M+ monthly npm downloads. Creator of @valibot & @formisch_dev, co-creator of standardschema.dev and prev engineer at @useMotion.

New York, USA

Joined December 2021

Pinned
Fabian Hiller
@FabianHiller
Jun 23
Formisch v1 is finally in RC! 🎉 After a year of long nights, the form library I wish existed when I was building complex forms for my first startup is here. Schema-first. Fully type-safe. Tiny (starts at 2.5 kB). And not just React — it runs on 6 frameworks from one core.
Formisch v1 RC is now available
From formisch.dev
30K
Fabian Hiller
@FabianHiller
Mar 19, 2025
I am excited to announce the release of Valibot v1, a 1 kB alternative to Zod with a type-safe and easy-to-remember API. Check out the announcement post now:
Valibot v1 - The 1 kB schema library
From valibot.dev
63K
Fabian Hiller
@FabianHiller
Jul 25, 2023
As part of my thesis, supervised by @mhevery and @RyanCarniato, I'm releasing a new open source project! Valibot is a schema library like @zodtypes, except that Valibot is modular and can be code split to a few hundred bytes. Read more in the announcement:
Introducing Valibot, a < 1kb Zod Alternative
From builder.io
143K
Fabian Hiller
@FabianHiller
Nov 18, 2024
Hey 👋 I am Fabian, the creator of Valibot, a TypeScript library with almost 2M monthly downloads and more than 6K stars on GitHub. I am looking for a US-based tech job starting in January. Feel free to share this post with your network! 🧩
71K
Fabian Hiller
@FabianHiller
Jul 26, 2023
Valibot, a < 1kB Zod alternative, is at almost 1,000 stars on GitHub one day after the official announcement! Thanks to every single person who supported us yesterday on release day. Your support means a lot to us! 💙
38K
Fabian Hiller
@FabianHiller
Oct 5, 2023
With this post I publish my bachelor thesis. 🧑‍🎓 As part of the research I looked at @zodtypes, @arktypeio and Typia and investigated how the bundle size of JavaScript libraries can be reduced. Thank you @mhevery and @RyanCarniato for your support.
This technique makes Valibot’s bundle size 10x smaller than Zod’s!
From builder.io
42K
Fabian Hiller
@FabianHiller
Jun 10, 2025
Is your React app slow and the code error-prone? Are unnecessary re-renders, `useMemo`, `useContext` and `memo` slowing you down? 😭 At @useMotion, we're investigating an approach that lets you use SolidJS components inside a React app. You can even pass state via props between
25K
Fabian Hiller
@FabianHiller
Jan 13, 2024
Great article by Matthew Kwong about the migration from @zodtypes to Valibot: mwskwong.com/blog/migrating…
33K
Fabian Hiller
@FabianHiller
Jun 6, 2024
After 3 months of hard work I am happy to announce that @valibot v0.31.0 is finally available. This is not a regular release as we have rewritten the whole library from scratch. Read the full announcement post now:
Valibot v0.31.0 is finally available
From valibot.dev
24K
Fabian Hiller
@FabianHiller
Jul 22, 2025
I think there is a misunderstanding. While Zod v4 Mini is much smaller than Zod v3, the bundle size is still ~80% bigger compared to @valibot. Example:
22K
Fabian Hiller
@FabianHiller
Jan 21, 2025
We have reached another big milestone! Valibot passed 1 million weekly downloads yesterday! I am speechless... 🙏
8.5K
Fabian Hiller
@FabianHiller
Jan 16, 2024
If you have been planning to migrate from Zod to Valibot, now might be the time. Our official migration guide will guide you through all the differences. I also promise that most of our API reference will be ready by the end of the month.
Migrate from Zod
From valibot.dev
32K
Fabian Hiller
@FabianHiller
Feb 10, 2025
Valibot v1 RC is out! 🧩 Many of you have been waiting for our first stable release, and with this blog post I am happy to announce that we are very very close.
valibot.dev
Valibot v1 RC is now available
Many of you have been waiting for our first stable release, and with this blog post I am happy to announce that we are very very close.
10K
Fabian Hiller
@FabianHiller
May 9, 2025
Valibot v1.1 introduced a native way to parse and stringify JSON. These new transformation actions automatically catch errors and handle all edge cases, and you can combine them with other schemas and actions for 100% reliable results. 🧩
9.9K