# kriasoft/isomorphic-style-loader

CSS style loader for Webpack that is optimized for isomorphic (universal) web apps.

Repository: https://github.com/kriasoft/isomorphic-style-loader
Canonical: https://ross.abutalabs.com/products/isomorphic-style-loader
Homepage: https://reactstarter.com
Language: JavaScript
License: MIT
License Family: permissive
Last push: 2026-08-11T12:24:05+00:00

## Health v2 (maintenance only)
Score: 83/100 (v2, computed 2026-09-02T17:46:02.011165+00:00)
- activity 97, release rhythm 55, longevity 100
- inputs: {"age_days": 3939, "days_push": 22, "days_rel": 89, "gap_med": 547, "n_releases_24m": 2}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 1272, forks 141 (observed 2026-08-28T04:04:12.153801+00:00)

## What it is
A Webpack CSS loader optimized for isomorphic (universal) web apps, similar to style-loader but supporting critical path CSS rendering. It exposes ._insertCss() to inject CSS into the DOM and ._getCss() to return a CSS string, with a withStyles higher-order component for React.

## Use cases
- inject css into the dom on the server and client for universal react apps
- render critical path css during server-side rendering
- use css modules with webpack in an isomorphic app
- get a css string from imported styles for ssr
- replace style-loader in a server-rendered webpack setup

## When to choose
- you build a server-rendered React app with Webpack 5 and need CSS injected on both server and client
- you want critical path CSS rendering with ._getCss() and ._insertCss() helpers
- you use CSS modules and need class names available server-side

## When to avoid
- you have a purely client-side app where standard style-loader suffices
- you use Vite, esbuild, or a bundler other than Webpack
- you rely on hoisted static properties from withStyles (removed in v6)

## Facets
- artifact type: library
- maturity: active
- function: css-framework, build-tool, ssr
- domain: web-development, frontend
- platform: cross-platform
- tags: webpack-loader, css-in-js, isomorphic, critical-css, react, style-loader, nodejs, web-server

## Member repositories
- kriasoft/isomorphic-style-loader (main) score 83

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:04:12.153801+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 2026-08-30T05:03:18.073160+00:00, confidence not recorded.
  - readme: https://github.com/kriasoft/isomorphic-style-loader (fetched 2026-08-28T04:04:12.153801+00:00, sha 2a92b606af23)
  - homepage: https://reactstarter.com (fetched 2026-08-29T12:14:40.019115+00:00, sha 5878da1e748a)
  - site_page: https://reactstarter.com/getting-started (fetched 2026-08-29T12:14:40.021742+00:00, sha 0811cda9e614)
  - registry_npm: https://registry.npmjs.org/isomorphic-style-loader (fetched 2026-08-29T12:14:40.023854+00:00, sha 141521e8ec8d)
- Data as of 2026-08-30T08:39:29.467469+00:00.