# Ultra-fast PostHog analytics with Jev, AI SDK + json-render

> PostHog analytics in a chat - powered by Jev How we read PostHog data without opening PostHog Fast, cheap PostHog analytics with Jev + Vercel Labs JSON rendering Generative analytics UI on top of P…

**Published:** 2026-09-24 | **Updated:** 2026-09-25 | **Categories:** Shorts

Watch: https://www.youtube.com/watch?v=xjCFbXXcS3s

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## Transcript

So, Roboto has always been hell-bent on moving fast as a team. We do love PostHog, by the way, but we hate using it to read the data.

If you haven't heard about Javelin, which is the new kid on the block, it is one of the fastest models out there right now that you can use. It is cheap, fast, and just does the job. So, if you haven't checked Javelin, check it out. In this demo, what we're using behind the scenes is Javelin, the model. We're also using Vercel Labs JSON rendering, and we're using GPT Luma for the chat.

This is for our own use case. We've created this. It pulls data directly from PostHog, and all I'll have to do is click the button: "How many people visited the home page today?" Did you see how fast that was? Take a moment to appreciate that, first of all. The only bit where it took longer was the data coming from PostHog, but did you see how the decision was made from Javelin showing "Oh, it was 42 visitors." Simple as. There is no bells and whistles. The data was fast, the model is cheap, and it just does the job.

You can use it for a number of use cases. The main selling point here is it's cheap and it's fast and it just does the job. Also, worth mentioning that Vercel Labs JSON rendering is amazing for doing these kind of things. All the UI that you're seeing here is rendering its dynamic data, and you can see how fast it is, how easy it is to read, and you don't have to hire a data analyst. I mean, do if you want to, but just saying.

## Frequently asked questions

### What is Javelin and why does Roboto use it?

Javelin is one of the fastest AI models available right now, and it's cheap too. We use it because it does the job without unnecessary complexity. The speed and cost efficiency let us focus on what matters: getting accurate answers from our data quickly.

### How fast is the demo you showed with PostHog data?

When I asked how many people visited the home page today, Javelin answered almost instantly with the correct number, 42 visitors. The only delay was pulling the data from PostHog itself, not the model processing it. That's the kind of performance we're talking about.

### What other tools are you using besides Javelin?

We're using Vercel Labs JSON rendering for the UI and GPT Luma for the chat component. The combination of these tools lets us build fast, readable interfaces that pull live data from PostHog and display results instantly without any bloat.

### Do you need a data analyst to use this setup?

Not necessarily. The interface makes it easy enough for anyone to ask questions about the data and get clear answers back. Of course, you can hire a data analyst if you want to, but this setup eliminates that requirement for basic queries.

### Why does Vercel Labs JSON rendering matter for this?

Vercel Labs JSON rendering is amazing because it handles dynamic data rendering efficiently. You can see how fast the UI updates, how easy it is to read the results, and it scales well without requiring heavy engineering on the frontend.

### What makes Javelin different from other AI models?

Javelin is cheap and fast, and it just works. There's no unnecessary processing or overhead. It makes decisions clearly and gets you the answer you need without any bells and whistles, which is exactly what we need when we're moving fast as a team.

### Can you use this approach for other use cases beyond analytics?

Yes, the setup is flexible enough for various use cases where you need to query data and get fast, clear answers. The main selling point is the combination of speed and cost, so any scenario where those matter is a good fit for this approach.