Instant Queries by Default
Try Gigabugs, our 1.2 million row bug tracker.
Sync engines enable instant UI by downloading data to the client before it's needed. All read and writes are local and synced with the server in the background.
But there's a catch: almost all realistic apps have way too much data to download ahead of time. There are usually complex permissions too — not all users can read and write all data.
We created Zero to solve these problems and bring the performance of sync to the entire web.
Try it out right now.
Our Gigabugs demo has 1.2 million rows, and loads in less than 2 seconds.
How it Works
Zero has two parts: a client and a server.
The server runs in the cloud and maintains a sync-optimized replica of your Postgres database.
On the client, you get an API that looks like an embedded database, but to which you can issue arbitrary “hybrid queries” that span the entire database, including the server.
Behind the scenes, Zero synchronizes query results continuously to a client-side persistent cache. This cache is used automatically for future queries whenever possible.
function Playlist({id}: {id: string}) {
const [playlist] = useQuery(
zero.query.playlist
.related('tracks', track => track
.related('album')
.related('artist')
.orderBy('playcount', 'asc'))
.where('id', id)
.one()
);
const onStar = (id: string, starred: boolean) => {
zero.mutate.track.update({id, starred});
};
// render playlist...
}Features
Instant Reads
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Instant Writes
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Automatic Reactivity
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Fast Startup
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Server Authority
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Easy Integration
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Our Users Say
Check out what our users have to say about Zero.
Zero completely changed how we think about real-time. The query-driven sync is genius — our app feels instant now.
We tried building our own sync layer. Should've just used Zero from day one. Saved us months of development time.
The permission system is incredibly powerful. We can finally give users real-time collaboration without worrying about data leaks.
Local-first with Zero means our app works offline and syncs seamlessly. Our users don't even notice when their connection drops.
The developer experience is top-notch. Write queries, get reactive updates. It's that simple.
Zero handles the hard parts of sync so we can focus on building features. The performance gains are unreal.
Pricing

Traditional SaaS
- Managed, monitored, and upgraded by Rocicorp
- Runs in our cloud infrastructure
- Zero setup — get started in minutes
BYOC (Bring Your Own Cloud)
- Managed, monitored, and upgraded by Rocicorp
- Runs in your own AWS VPC
- Data stays in your org with revocable access
Get in Touch
Hosting is in private beta. Message us and we'll get you onboarded.