Rio – Open Source Web Apps in Pure Python, No JS/HTML/CSS Needed
Hey HN, Over the past 10 months, my friends and I created an open source project called Rio to help Python developers build modern web apps without needing HTML, CSS, or JavaScript. Whether you're working on a simple internal tool or a complex multi-page app, Rio lets you stay in the Python ecosystem without needing to learn frontend frameworks. With Rio, the UI is defined using Python components, inspired by React and Flutter. Instead of writing HTML/CSS, you compose reusable UI elements in Python and let Rio handle rendering and state updates. The backend and frontend stay seamlessly…
What it does
In the maker’s words, at launch
Hey HN, Over the past 10 months, my friends and I created an open source project called Rio to help Python developers build modern web apps without needing HTML, CSS, or JavaScript. Whether you're working on a simple internal tool or a complex multi-page app, Rio lets you stay in the Python ecosystem without needing to learn frontend frameworks. With Rio, the UI is defined using Python components, inspired by React and Flutter. Instead of writing HTML/CSS, you compose reusable UI elements in Python and let Rio handle rendering and state updates. The backend and frontend stay seamlessly connected using WebSockets, so data syncs automatically without manual API calls. Since Rio is fully Python-native, you can integrate it with any Python library, from data science tools to AI models. Many Python projects rely on popular libraries like React internally, but the core benefits and elegance of these libraries are often diluted in the process. Unlike wrapper frameworks, Rio is built from scratch, offering a cleaner, faster, and more efficient development experience specifically for Python. We’ve seen users build everything from CRM tools to dashboards, LLM interfaces, and interactive reports using Rio. If you’re a Python developer who has wanted a better way to build web apps without learning JavaScript, we’d love to hear your thoughts! [Github] https://github.com/rio-labs/rio [Website] https://rio.dev
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