# Preswald

A Python static-site generator for interactive data apps that bundles compute, data access, and UI into a single offline-capable HTML file using Pyodide, DuckDB, Pandas, and Plotly.

Preswald is a static-site generator for building interactive data apps in Python that run entirely in the browser, with no local dependencies, no server, and no internet connection required. Built on a WASM runtime combining Pyodide and DuckDB, it packages compute, data access, and UI into a self-contained, portable, shareable file.

Apps are written in Python rather than in a notebook or a JavaScript framework, using prebuilt UI components such as tables, charts, and forms, and a reactive engine that only re-runs what a change actually affects, powered by a dependency graph. Exporting a project bundles the Python code, data, and DuckDB queries into a static site that preserves the app's UI, logic, and reactive state, so it can run offline in any modern browser, be shared as a folder, or be embedded in a hosting platform, without the recipient needing to install anything.

Website: https://www.preswald.com/