Lightning Design System
Salesforce's CSS framework and design tokens.
The Salesforce Lightning Design System is a CSS framework rather than a component library. It ships class names, design tokens and markup patterns, and leaves the behaviour to whatever framework you are in, which in Salesforce's world is usually Lightning Web Components.
At a glance
| Install | npm install @salesforce-ux/design-system, or a CDN link |
| Delivery | CSS classes and tokens, no JavaScript components |
| Current line | Lightning Design System 2 |
| Licence | BSD-3-Clause |
| MCP server | not published |
| Docs | published on zeroheight rather than as code documentation |
Where it is mandatory
If you build on the Salesforce platform, this is the visual contract. Lightning Web Components consume SLDS classes, and an app that ignores them looks foreign inside the org. That is the entire use case, and within it there is no alternative.
Two things to check before adopting
The documentation has moved to a zeroheight-hosted site, separate from the code repository, so design guidance and implementation reference live in different places and can drift.
The GitHub repository's last tagged release is dated July 2025. Salesforce publishes to npm on its own cadence and the package version is well past 2.264, so the repository timeline is not the whole picture, but it is worth verifying the release channel you depend on.
Choose it if
- You build on Salesforce. There is no real choice to make.
- You want a mature CSS token system under BSD-3-Clause.
Look elsewhere if
- You need interactive components. There are none here, by design.
- You are not in the Salesforce ecosystem. The visual language serves that context and nothing else.
