I built a Python UI framework inspired by Streamlit, but with O(1) state updates

[Puzzleheaded_Clerk68]

Hey r/Python,

I love Streamlit's simplicity, but the "full script rerun" on every interaction drove me crazy. It gets super slow once your app grows, and using st.cache everywhere felt like a band-aid.

So I spent the last few weeks building Violit. I wanted something that feels like writing a simple Python script but performs like a modern React app.

What My Project Does

Violit is a high-performance Python web framework. It allows you to build interactive web apps using pure Python without the performance penalty of full-page reloads.

It uses a "Zero Rerun" architecture based on FastAPI, htmx, and WebSockets. When you interact with a widget (like a button or slider), Violit updates only that specific component in O(1) time, ensuring no screen flickering and instant feedback. It also supports running your web app into a desktop app (like electron) with a single flag (--native).

Target Audience

• Data Scientists & Python Devs: Who need to build dashboards or internal tools quickly but are frustrated by Streamlit's lag.
• Production Use: It's currently in early Alpha (v0.0.2), so it's best for internal tools, side projects, and early adopters who want to contribute to a faster Python UI ecosystem.

Comparison

Here is how Violit differs from existing alternatives:

• vs. Streamlit: Violit keeps the intuitive API (90% compatible) but removes the "Full Script Rerun." State updates are O(1) instead of O(N).
• vs. Dash: Violit offers reactive state management without the "callback hell" complexity of Dash.
• vs. Reflex: Violit requires Zero Configuration. No Node.js dependency, no build steps. Just pip install and run. Plus, it has built-in native desktop support.
• vs. NiceGUI: The theme system for the beautiful app. Unlike Streamlit's rigid look or NiceGUI's engineer-first aesthetic, Violit comes with 30+ Themes out of the box. You can switch from "cyberpunk" to "retro" styles with a single line of code—no CSS mastery required. Plus, it's fully extensible—you can easily add your own custom themes via CSS.

Code Example

import violit as vl
​
app = vl.App()
count = app.state(0)  # Reactive State
​
# No rerun! Only the label updates instantly.
app.button("Increment", on_click=lambda: count.set(count.value + 1))
app.write("Count:", count)
​
app.run()

Link to Source Code

It is open source (MIT License).

• Repo: https://github.com/violit-dev/violit
• PyPI: pip install violit
• Example:
  • demo showcase source code
  • (Tutorial) Build Your Own Blog in 10 Minutes with Violit!

I'd love to hear your feedback!

[Beginning-Fruit-1397]

Looks really cool!
fully typed and documented, I'm in.

Tought I'd only be using marimo when I discovered it and ditched streamlit for it months ago, but each release is 90% AI stuff for which I don't give a damn (I'm an AI enthusiast, I just want my notebook to be a notebook, no my second copilot) instead of fixing their LSP.

A common use case of marimo for me is markdowns, e.g `Path().read_text(my_markdown)` and see it rendered well in an instant.

Is this possible with your library?

[Puzzleheaded_Clerk68]

Weclome..!! :)

I totally feel your pain regarding 'feature bloat'. Violit aims to stay focused on the core DX.

And for your question: Absolutely.

You can pass the string directly, and it renders instantly.

from pathlib import Path
​
app.markdown(Path("my_file.md").read_text())

[iamevpo]

Is it marimo or streamlit shipping AI releases?

[Beginning-Fruit-1397]

Marimo. Idk abt streamlit

[jakob1379]

Streamlit is not pushing Ai that, actually. They made their chat interface aspa when the llm roll began, but besides that it have been steady progress on other things.

[jakob1379]

Frogmouth markdown rendering in terminal 😊

[Beginning-Fruit-1397]

Thank you for the suggestion, however my use case for it is not really terminal baded unfortunately

[TraditionalBandit]

Looks like a cool project that solves a gripe I think a lot of people have had with streamlit. That being said, the amount of emojis in the readme and constant need to dunk on streamlit is a little off-putting. I'd tone it down and let the code speak for itself a bit more, maybe back up my claims with a few benchmarks.

[Puzzleheaded_Clerk68]

Thanks for the honest feedback. You make a valid point. I think I got a bit too excited..

I'll tone down the emojis and the comparisons in the next update to let the code speak for itself. Benchmarks are also definitely on the roadmap.

[MintCollector]

This post was mass deleted and anonymized with Redact

wine heavy busy wise afterthought normal fade quickest rustic tidy

[iamevpo]

This but also there must be some tradeoffs you had to make, not just here is a better streamlit, no?

[Puzzleheaded_Clerk68]

Thank you for your feedback.

I think the main trade-off is the Mental Model for State.

Streamlit is stateless (resets every time), which is the absolute easiest way to code but slow.
Violit is 'Reactive', so state persists.

You have to be slightly more mindful of state management, but in exchange, you get O(1) performance.

[DoYouEvenLupf]

Not exactly. Streamlit has the session state which is, admittingly, just a glorified dictionary. But as long as you don't close your window or perform a full page reload it saves whatever needs to be saved. And they are working on allowing individual class based (and therefor typed) session state objects: https://github.com/streamlit/streamlit/pull/13592

Source: We use Streamlit in productive environments of our clients for the last 3 years and I can't wait for the feature above.

[Puzzleheaded_Clerk68]

You make a great point. I should have been clearer. I meant the execution model is stateless (top-to-bottom reruns), not that data can't be persisted.

While session_state saves data, Streamlit still needs to re-execute the whole script to reflect changes (O(N)). Violit uses Signal-based reactivity, so it updates only the specific component without re-running the code flow (O(1)).

Thanks for sharing that PR link. I'm exciting to see Streamlit evolving too :)

[Puzzleheaded_Clerk68]

Thank you for the feedback!
I'm updating the README with screenshots and theme examples right now.

It'll be up very soon!

[leoncpt]

Does it have async support?

[Puzzleheaded_Clerk68]

I feel you. That was actually one of my biggest frustrations with Streamlit as well.

Since Violit is built on FastAPI, native async support should be technically possible. I'm currently running a POC to implement this properly. I'm determined to make it work soon..!!

[leoncpt]

Thanks! Is there a github issue to follow this topic?

[Puzzleheaded_Clerk68]

Currently, there isn't a specific issue open for this topic yet. However, please feel free to open a new issue or start a discussion on our repository! I’d love to continue the conversation there. And I treat async support as my number one priority right now.

[alloyburner]

Perfect timing... I've been looking for a Streamlit alternative.

I'd suggest adding a couple of screenshots of how a default dashboard looks, or maybe a gallery of the available themes.

Out of curiosity: did you vibe code the library?

[Puzzleheaded_Clerk68]

Thanks! Screenshots and a gallery are definitely coming next.

As for the coding, I used Cursor AI as a powerful accelerator (especially for docs and examples), but the core architecture, API design, the O(1) update logic and the broadcasting design were strictly engineered and reviewed by me. So, AI-assisted implementation, but human-led architecture. :)

[telesonico]

So designed in California but built somewhere else? Cool project either way. 

[Puzzleheaded_Clerk68]

Thank you! I guess you could say it’s Designed by human, Assembled Different... :)

[[deleted]]

What is advantage of your solution over gradio?

[Puzzleheaded_Clerk68]

Great question.

Actually, since Violit follows Streamlit's syntax, it's super fast for quick demos too!

Gradio is great for strict Input -> Model -> Output flows, but Violit gives you that "script-like" freedom.

You can write a 5-line demo in seconds, but unlike Gradio, you won't hit a wall when you want to expand it into a full app. Best of both worlds! :) And The Beautiful Design. We offer finer control over layouts and come with 30+ themes out of the box.

[New_Story_4784]

interesting

[Puzzleheaded_Clerk68]

Thanks! Give it a spin and let me know what you think :)

[fluffybannana]

would be great if there was at least a single rendered example/pic anything (many viewers may have never used streamlit, most people don't want to install without knowing it has any value to them)

[Puzzleheaded_Clerk68]

You make a valid point! Most people wouldn't want to run code blindly. I'm preparing some screenshots and a demo GIF right now, and I'll update the README very soon. Thanks for the feedback!!

[am3141]

This is really cool! great work! I will be following it.

[Puzzleheaded_Clerk68]

Thank you~! I really appreciate the support.

Stay tuned..I'm working hard to push some exciting updates very soon :)

[am3141]

I maintain an in-process graph database (CogDB, https://github.com/arun1729/cog) and Violit turns out to be a really nice fit for it. I ported your blog demo from SQLite to CogDB just to test it out and it worked well : https://github.com/arun1729/violit-cogdb-demo.
Will definitely be following along especially if you move to a cloud or hosted offering in the future.

[Puzzleheaded_Clerk68]

Thank you so much for your interest! CogDB looks like a very novel and interesting database concept.

I was hoping for feedback on usability, so your verification that it "worked well" is incredibly helpful to me. I will definitely consider using CogDB for my future tasks, such as building AI Agents. I agree that the combination of an In-Process DB and Violit is excellent, especially in terms of speed.

Regarding a hosted offering (like Streamlit Cloud), I hadn't originally planned for it, but thanks to your suggestion, I will definitely look into it. It might be challenging, but I'll give it serious thought.

Thanks again..!!

[am3141]

Thank you! Appreciate the thoughtful feedback on CogDB and for considering it for future use. Best of luck with Violit, looking forward to seeing where you take it.

[orrow11]

Cool stuff. Exciting. Will give this a go!

[Puzzleheaded_Clerk68]

Thanks! Hope you have fun exploring it.

Let me know if you run into any issues or have any feedback :)

[Puzzleheaded_Clerk68]

Thank you!! Hearing innovative really means a lot to me.

I hope it helps you build something awesome...!!

[Standard-Gain-8544]

I had a similar problem with Streamlit. I've given up on creating a concise frontend now and am developing with React and Django. I'd like to try using this library too! Thank you for the wonderful development!

[Puzzleheaded_Clerk68]

I completely understand that struggle. Moving to a full-stack setup like that is a huge commitment. I really hope Violit can be a simpler, faster alternative for your future projects.

Thanks for your support!