Show HN: Browser based state machine simulator and visualizer

The configuration reminds me a lot of XState, which has a beautiful visualizer/simulator (with a new version on the way I think): https://stately.ai/viz

This is cool too! I love state machines.

Re: Show HN: Browser based state machine simulator and visualizer

#5

Post by davidkpiano » Sun, Feb 08, 2026, 2:53 AM UTC

Really cool! Love the XState-inspired API ;-)

Re: Show HN: Browser based state machine simulator and visualizer

#6

Post by sridhar87 » Mon, Feb 09, 2026, 6:52 PM UTC

steve_adams_86 wrote: post #4

The configuration reminds me a lot of XState, which has a beautiful visualizer/simulator (with a new version on the way I think): https://stately.ai/viz This is cool too! I love state machines.

Thanks for checking out.

Yes, it looks similar to XState. When I built it, I didn't know of XState, but of course, I did use a lot of AI to create this, so the configuration is similar to XState.

But my plan is to see if there is opportunity with this elsewhere, orthogonal to what stately seems to be doing.

Re: Show HN: Browser based state machine simulator and visualizer

#7

Post by sridhar87 » Mon, Feb 09, 2026, 6:53 PM UTC

smusamashah wrote: post #3

You meant this perhaps? https://svylabs.github.io/smacthat/

Yeah, smacthat!

Re: Show HN: Browser based state machine simulator and visualizer

#8

Post by sridhar87 » Mon, Feb 09, 2026, 6:54 PM UTC

smusamashah wrote: post #2

I get a 404 immediately

I got a cool name for the project: smacthat, so renamed the repo. But I couldn't delete this post or edit it. Sorry, but thanks for trying out.

Re: Show HN: Browser based state machine simulator and visualizer

#9

Post by sridhar87 » Mon, Feb 09, 2026, 6:57 PM UTC

davidkpiano wrote: post #5

Really cool! Love the XState-inspired API ;-)

Thanks for checking out.

Actually I didn't know of XState when I built this, I had built this for my own workflow.

I did use AI to build this, so credits to AI for coming up with the right model, inspired by XState.

My plan is to build a slightly orthogonal version of what stately / xstate offers, even though right now it looks similar.

You can check out eigenarc.com for how I'm thinking of this.

Re: Show HN: Browser based state machine simulator and visualizer

#10

Post by steve_adams_86 » Mon, Feb 09, 2026, 9:25 PM UTC

sridhar87 wrote: post #6

steve_adams_86 wrote: post #4

The configuration reminds me a lot of XState, which has a beautiful visualizer/simulator (with a new version on the way I think): https://stately.ai/viz This is cool too! I love state machines.

Thanks for checking out. Yes, it looks similar to XState. When I built it, I didn't know of XState, but of course, I did use a lot of AI to create this, so the configuration is similar to XState. But my plan is to see if there is opportunity with this elsewhere, orthogonal to what stately seems to be doing.

> so the configuration is similar to XState

In my opinion this is a good thing. It's a really well-designed API. It's easily my favourite approach to defining state machines that I've encountered across several languages.

> see if there is opportunity with this elsewhere

Any plans to share yet? This sounds interesting!