# basscss/basscss

Low-level CSS Toolkit – the original Functional/Utility/Atomic CSS library

Repository: https://github.com/basscss/basscss
Canonical: https://ross.abutalabs.com/products/basscss
Homepage: https://basscss.com
Language: CSS
License: MIT
License Family: permissive
Topics: basscss, css, atomic-css, utility-css, utility, functional-css, design-system, oocss
Last push: 2022-12-30T17:37:47+00:00

## Health v2 (maintenance only)
Score: 23/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 0, release rhythm 8, longevity 100
- inputs: {"age_days": 4701, "days_push": 1342, "days_rel": null, "gap_med": null, "n_releases_24m": 0}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 5897, forks 294 (observed 2026-08-28T04:09:32.051129+00:00)

## What it is
Basscss is a low-level CSS toolkit and the original functional/atomic CSS library, providing a lightweight collection of immutable utility classes for typography, layout, and color. Version 8 is declared final and stable, with modular packages and addons available on npm.

## Use cases
- style a website with utility classes instead of writing custom CSS
- rapidly prototype designs in the browser
- add a tiny utility CSS layer to an existing project
- build a design system on composable atomic classes
- reduce CSS boilerplate for responsive layouts
- find a lightweight alternative to Bootstrap for styling

## When to choose
- you want a tiny (~2-3 KB) utility CSS library with no side effects
- you prefer immutable, composable atomic classes over component frameworks
- you need stable, unchanging styles for a long-lived project
- you want modular packages you can pick from on npm

## When to avoid
- you need actively developed tooling or modern features like CSS variables and utility generation
- you want a component library with prebuilt UI widgets like Bootstrap or Tailwind's ecosystem
- you prefer JIT-generated utility classes with a build step

## Facets
- artifact type: library
- maturity: maintenance
- function: css-framework, ui-components, templating
- domain: web-development, frontend, web-design
- platform: browser
- tags: atomic-css, utility-css, functional-css, design-system, oocss, lightweight, web-server, nodejs

## Member repositories
- basscss/basscss (main) score 23

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:09:32.051129+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 2026-08-29T17:51:19.752882+00:00, confidence not recorded.
  - readme: https://github.com/basscss/basscss (fetched 2026-08-28T04:09:32.051129+00:00, sha dbb7f27a6645)
  - homepage: https://basscss.com (fetched 2026-08-29T08:46:50.817510+00:00, sha e2cb3c3c1a8f)
  - site_page: https://basscss.com/v7 (fetched 2026-08-29T08:46:50.821570+00:00, sha c5bfcf430bef)
- Data as of 2026-08-30T08:39:29.467469+00:00.