# StructuredLabs/preswald

Preswald is a WASM packager for Python-based interactive data apps: bundle full complex data workflows, particularly visualizations, into single files, runnable completely in-browser, using Pyodide, DuckDB, Pandas, and Plotly, Matplotlib, etc. Build dashboards, reports, and notebooks that run offline, load fast, and share like a document.

Repository: https://github.com/StructuredLabs/preswald
Canonical: https://ross.abutalabs.com/products/preswald
Homepage: https://www.preswald.com/
Language: Python
License: Apache-2.0
License Family: permissive
Topics: ai, analytics, data, analytics-engineering, copilot, data-applications, data-infrastructure, data-pipelines, data-sdk, data-visualization, gpt, llm, open-source, python, schema-management, vscode
Last push: 2026-06-11T23:01:11+00:00

## Health v2 (maintenance only)
Score: 62/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 87, release rhythm 40, longevity 44
- inputs: {"age_days": 627, "days_push": 83, "days_rel": 454, "gap_med": 4, "n_releases_24m": 26}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 4279, forks 648 (observed 2026-08-28T04:08:41.161069+00:00)

## What it is
Preswald is a Python framework and static-site generator for building interactive data apps that bundle compute, data access, and UI into a single self-contained HTML file. It runs entirely in the browser via a WASM runtime (Pyodide, DuckDB), requiring no server or local dependencies and working offline.

## Use cases
- build interactive dashboards in python
- share a data report as a single html file
- run data analysis offline in the browser
- package a pandas/duckdb workflow for a stakeholder
- create a self-contained data notebook
- prototype data apps without a backend server
- keep sensitive data analysis fully local

## When to choose
- you need to distribute a data app as one shareable file
- recipients shouldn't install anything or run a server
- data privacy requires fully local, offline execution
- you want reactive python dashboards with built-in UI components

## When to avoid
- you need a multi-user server-backed web application
- your datasets are too large for in-browser WASM memory
- you need heavy server-side compute or database connections
- you require fine-grained control over frontend JS frameworks

## Facets
- artifact type: framework
- maturity: active
- function: data-visualization, static-site-generator, web-framework, charts, wasm, analytics
- domain: data-visualization, data-science, web-development, analytics, developer-tools
- platform: python, browser, wasm, cross-platform
- tags: pyodide, duckdb, single-file-apps, offline-apps, dashboards, data-apps, reactive-ui

## Member repositories
- StructuredLabs/preswald (main) score 62

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:08:41.161069+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-29T18:21:58.683382+00:00, confidence not recorded.
  - readme: https://github.com/StructuredLabs/preswald (fetched 2026-08-28T04:08:41.161069+00:00, sha 29ea9a0d446f)
  - homepage: https://www.preswald.com/ (fetched 2026-08-29T09:11:20.179819+00:00, sha 600086e7f8a5)
- Data as of 2026-08-30T08:39:29.467469+00:00.