TACTICALSep 6, 2026

The most interesting & ambitious things built on GPT-6 Astra (so far)

GPT-6 Astra shipped, and I hunted it on Product Hunt the same week.

Then the timeline lit up in that familiar way: builders posting demos faster than anyone could bookmark them.

People started making ridiculous things. Playable games. Three.js worlds. Blender houses. Unreal civilizations. PostHog dashboards that assemble themselves across three browser tabs while you watch.

I wrote up the hunt separately (I hunted GPT-6 Astra. It went #1 on Product Hunt.). This post is the other half: a curated compilation of the most interesting and ambitious builds I saw in the first couple of days.

Nothing here is ranked. I grouped them by theme so you can skim for what you care about. Links go to the original posts, plus a couple of official OpenAI showcases.

If you prefer filters, there's a live directory too: built-on-astra-kp.netlify.app

Games

Void Explorer / Sunwake / Hollowflux (OpenAI Developers). Official showcase: Void Explorer (Three.js WebGPU), Sunwake ocean boat, Hollowflux 2D RPG.

Three.js & WebGL

Building games with Astra (Three.js + WebGPU) (OpenAI Developers). TypeScript/Vite, Three.js node materials / TSL, terrain workers.

3D / Blender / Unreal

Architecture & Art

Solace house + HELIOS + Shipyard + Giverny (OpenAI Developers). Official archviz: cinematic Blender house, UE5 walkthrough, Dyson sphere, cruiser, Monet garden.

Agents & Computer Use

Analytics & Dashboards

Apps & Tools

What I'm taking away

We already knew AI can write code. That part stopped being surprising a while ago.

What got me watching these demos on loop is how Astra closes the loop. You play the thing, complain about one detail, get a new build, and play again (sometimes in the same session). Riley Brown's COD-style demo is the clearest version of that. Akarsh's PostHog dashboards are the work version of the same idea: less babysitting, more “fix it while I watch.”

If you're building in public right now and you're not stress-testing Astra on the hardest thing on your plate.. you're leaving free momentum on the table.

Got a wild Astra build I missed? Reply on @thisiskp_ and I'll add it.

Enjoyed this? I write KP's Column weekly for 5,600+ founders. And I genuinely read every reply - say hi at @thisiskp_.