Writing Plugins
Extending Tailwind with reusable third-party plugins.
Overview
Plugins let you register new styles for Tailwind to inject into the user’s stylesheet using JavaScript instead of CSS.
To get started with your first plugin, import Tailwind’s plugin
function from tailwindcss/plugin
, and call it with an anonymous function as the first argument in the plugins
list in your config file:
// tailwind.config.js
const plugin = require('tailwindcss/plugin')
module.exports = {
plugins: [
plugin(function({ addUtilities, addComponents, e, prefix, config }) {
// Add your custom styles here
}),
]
}
Plugin functions receive a single object argument that can be destructured into several helper functions:
addUtilities()
, for registering new utility stylesaddComponents()
, for registering new component stylesaddBase()
, for registering new base stylesaddVariant()
, for registering custom variantse()
, for escaping strings meant to be used in class namesprefix()
, for manually applying the user’s configured prefix to parts of a selectortheme()
, for looking up values in the user’s theme configurationvariants()
, for looking up values in the user’s variants configurationconfig()
, for looking up values in the user’s Tailwind configurationpostcss
, for doing low-level manipulation with PostCSS directly
Adding utilities
The addUtilities
function allows you to register new styles to be output (along with the built-in utilities) at the @tailwind utilities
directive.
Plugin utilities are output in the order they are registered, after built-in utilities, so if a plugin targets any of the same properties as a built-in utility, the plugin utility will take precedence.
To add new utilities from a plugin, call addUtilities
, passing in your styles using CSS-in-JS syntax:
// tailwind.config.js
const plugin = require('tailwindcss/plugin')
module.exports = {
plugins: [
plugin(function({ addUtilities }) {
const newUtilities = {
'.skew-10deg': {
transform: 'skewY(-10deg)',
},
'.skew-15deg': {
transform: 'skewY(-15deg)',
},
}
addUtilities(newUtilities)
})
]
}
Prefix and important preferences
By default, plugin utilities automatically respect the user’s prefix
and important
preferences.
That means that given this Tailwind configuration:
// tailwind.config.js
module.exports = {
prefix: 'tw-',
important: true,
// ...
}
…the example plugin above would generate the following CSS:
.tw-skew-10deg {
transform: skewY(-10deg) !important;
}
.tw-skew-15deg {
transform: skewY(-15deg) !important;
}
If necessary, you can opt out of this behavior by passing an options object as a second parameter to addUtilities
:
// tailwind.config.js
const plugin = require('tailwindcss/plugin')
module.exports = {
plugins: [
plugin(function({ addUtilities }) {
const newUtilities = {
// ...
}
addUtilities(newUtilities, {
respectPrefix: false,
respectImportant: false,
})
})
]
}
Responsive and pseudo-class variants
To generate responsive, hover, focus, active, or other variants of your styles, specify the variants you’d like to generate using the variants
option:
// tailwind.config.js
const plugin = require('tailwindcss/plugin')
module.exports = {
plugins: [
plugin(function({ addUtilities }) {
const newUtilities = {
// ...
}
addUtilities(newUtilities, {
variants: ['responsive', 'hover'],
})
})
]
}
If you only need to specify variants and don’t need to opt-out of the default prefix or important options, you can also pass the array of variants as the second parameter directly:
// tailwind.config.js
const plugin = require('tailwindcss/plugin')
module.exports = {
plugins: [
plugin(function({ addUtilities }) {
const newUtilities = {
// ...
}
addUtilities(newUtilities, ['responsive', 'hover'])
})
]
}
If you’d like the user to provide the variants themselves under the variants
section in their tailwind.config.js
file, you can use the variants()
function to get the variants they have configured:
// tailwind.config.js
const plugin = require('tailwindcss/plugin')
module.exports = {
variants: {
customPlugin: ['responsive', 'hover'],
},
plugins: [
plugin(function({ addUtilities, variants }) {
const newUtilities = {
// ...
}
addUtilities(newUtilities, variants('customPlugin'))
})
]
}
Adding components
The addComponents
function allows you to register new styles to be output at the @tailwind components
directive.
Use it to add more opinionated, complex classes like buttons, form controls, alerts, etc; the sort of pre-built components you often see in other frameworks that you might need to override with utility classes.
To add new component styles from a plugin, call addComponents
, passing in your styles using CSS-in-JS syntax:
// tailwind.config.js
const plugin = require('tailwindcss/plugin')
module.exports = {
plugins: [
plugin(function({ addComponents }) {
const buttons = {
'.btn': {
padding: '.5rem 1rem',
borderRadius: '.25rem',
fontWeight: '600',
},
'.btn-blue': {
backgroundColor: '#3490dc',
color: '#fff',
'&:hover': {
backgroundColor: '#2779bd'
},
},
'.btn-red': {
backgroundColor: '#e3342f',
color: '#fff',
'&:hover': {
backgroundColor: '#cc1f1a'
},
},
}
addComponents(buttons)
})
]
}
Prefix and important preferences
By default, component classes automatically respect the user’s prefix
preference, but they are not affected by the user’s important
preference.
That means that given this Tailwind configuration:
// tailwind.config.js
module.exports = {
prefix: 'tw-',
important: true,
// ...
}
…the example plugin above would generate the following CSS:
.tw-btn {
padding: .5rem 1rem;
border-radius: .25rem;
font-weight: 600;
}
.tw-btn-blue {
background-color: #3490dc;
color: #fff;
}
.tw-btn-blue:hover {
background-color: #2779bd;
}
.tw-btn-blue {
background-color: #e3342f;
color: #fff;
}
.tw-btn-blue:hover {
background-color: #cc1f1a;
}
Although there’s rarely a good reason to make component declarations important, if you really need to do it you can always add !important
manually:
// tailwind.config.js
const plugin = require('tailwindcss/plugin')
module.exports = {
plugins: [
plugin(function({ addComponents }) {
const buttons = {
'.btn': {
padding: '.5rem 1rem !important',
borderRadius: '.25rem !important',
fontWeight: '600 !important',
},
// ...
}
addComponents(buttons)
})
]
}
All classes in a selector will be prefixed by default, so if you add a more complex style like:
// tailwind.config.js
const plugin = require('tailwindcss/plugin')
module.exports = {
prefix: 'tw-',
plugins: [
plugin(function({ addComponents }) {
const components = {
// ...
'.navbar-inverse a.nav-link': {
color: '#fff',
}
}
addComponents(components)
})
]
}
…the following CSS would be generated:
.tw-navbar-inverse a.tw-nav-link {
color: #fff;
}
To opt out of prefixing, pass an options object as a second parameter to addComponents
:
// tailwind.config.js
const plugin = require('tailwindcss/plugin')
module.exports = {
prefix: 'tw-',
plugins: [
plugin(function({ addComponents }) {
const components = {
// ...
}
addComponents(components, {
respectPrefix: false
})
})
]
}
Responsive and pseudo-class variants
To generate responsive, hover, focus, active, or other variants of your components, specify the variants you’d like to generate using the variants
option:
// tailwind.config.js
const plugin = require('tailwindcss/plugin')
module.exports = {
plugins: [
plugin(function({ addComponents }) {
const newComponents = {
// ...
}
addComponents(newComponents, {
variants: ['responsive', 'hover'],
})
})
]
}
If you only need to specify variants and don’t need to opt-out of the default prefix or important options, you can also pass the array of variants as the second parameter directly:
// tailwind.config.js
const plugin = require('tailwindcss/plugin')
module.exports = {
plugins: [
plugin(function({ addComponents }) {
const newComponents = {
// ...
}
addComponents(newComponents, ['responsive', 'hover'])
})
]
}
If you’d like the user to provide the variants themselves under the variants
section in their tailwind.config.js
file, you can use the variants()
function to get the variants they have configured:
// tailwind.config.js
const plugin = require('tailwindcss/plugin')
module.exports = {
variants: {
customPlugin: ['responsive', 'hover'],
},
plugins: [
plugin(function({ addComponents, variants }) {
const newComponents = {
// ...
}
addComponents(newComponents, variants('customPlugin'))
})
]
}
Adding base styles
The addBase
function allows you to register new styles to be output at the @tailwind base
directive.
Use it to add things like base typography styles, opinionated global resets, or @font-face
rules.
To add new base styles from a plugin, call addBase
, passing in your styles using CSS-in-JS syntax:
// tailwind.config.js
const plugin = require('tailwindcss/plugin')
module.exports = {
plugins: [
plugin(function({ addBase, config }) {
addBase({
'h1': { fontSize: config('theme.fontSize.2xl') },
'h2': { fontSize: config('theme.fontSize.xl') },
'h3': { fontSize: config('theme.fontSize.lg') },
})
})
]
}
Since base styles are meant to target bare selectors like div
, h1
, etc., they do not respect the user’s prefix
or important
configuration.
Escaping class names
If your plugin generates classes that contain user-provided strings, you can use the e
function to escape those class names to make sure non-standard characters are handled properly automatically.
For example, this plugin generates a set of .rotate-{angle}
utilities where {angle}
is a user provided string. The e
function is used to escape the concatenated class name to make sure classes like .rotate-1/4
work as expected:
// tailwind.config.js
const _ = require('lodash')
const plugin = require('tailwindcss/plugin')
module.exports = {
theme: {
rotate: {
'1/4': '90deg',
'1/2': '180deg',
'3/4': '270deg',
}
},
plugins: [
plugin(function({ addUtilities, config, e }) {
const rotateUtilities = _.map(config('theme.rotate'), (value, key) => {
return {
[`.${e(`rotate-${key}`)}`]: {
transform: `rotate(${value})`
}
}
})
addUtilities(rotateUtilities)
})
]
}
This plugin would generate the following CSS:
.rotate-1\/4 {
transform: rotate(90deg);
}
.rotate-1\/2 {
transform: rotate(180deg);
}
.rotate-3\/4 {
transform: rotate(270deg);
}
Be careful to only escape content you actually want to escape; don’t pass the leading .
in a class name or the :
at the beginning pseudo-classes like :hover
or :focus
or those characters will be escaped.
Additionally, because CSS has rules about the characters a class name can start with (a class can’t start with a number, but it can contain one), it’s a good idea to escape your complete class name (not just the user-provided portion) or you may end up with unnecessary escape sequences:
// Will unnecessarily escape `1`
`.rotate-${e('1/4')}`
// => '.rotate-\31 \/4'
// Won't escape `1` because it's not the first character
`.${e('rotate-1/4')}`
// => '.rotate-1\/4'
Manually prefixing selectors
If you’re writing something complex where you only want to prefix certain classes, you can use the prefix
function to have fine-grained control of when the user’s configured prefix is applied.
For example, if you’re creating a plugin to be reused across a set of internal projects that includes existing classes in its selectors, you might only want to prefix the new classes:
// tailwind.config.js
const plugin = require('tailwindcss/plugin')
module.exports = {
prefix: 'tw-',
plugins: [
plugin(function({ addComponents, prefix }) {
addComponents({
[`.existing-class > ${prefix('.new-class')}`]: {
backgroundColor: '#fff',
}
})
})
]
}
This would generate the following CSS:
.existing-class > .tw-new-class {
background-color: #fff;
}
The prefix
function will prefix all classes in a selector and ignore non-classes, so it’s totally safe to pass complex selectors like this one:
prefix('.btn-blue .w-1\/4 > h1.text-xl + a .bar')
// => '.tw-btn-blue .tw-w-1\/4 > h1.tw-text-xl + a .tw-bar'
Referencing the user’s config
The config
, theme
, and variants
functions allow you to ask for a value from the user’s Tailwind configuration using dot notation, providing a default value if that path doesn’t exist.
For example, this simplified version of the built-in container plugin uses the theme
function to get the user’s configured breakpoints:
// tailwind.config.js
const _ = require('lodash')
const plugin = require('tailwindcss/plugin')
module.exports = {
plugins: [
plugin(function({ addComponents, theme }) {
const screens = theme('screens', {})
const mediaQueries = _.map(screens, width => {
return {
[`@media (min-width: ${width})`]: {
'.container': {
'max-width': width,
},
},
}
})
addComponents([
{ '.container': { width: '100%' } },
...mediaQueries,
])
})
]
}
Note that the theme
function is really just a shortcut for using the config
function to access the theme section of the user’s config:
// These are equivalent
config('theme.screens')
theme('screens')
If you’d like to reference the user’s variants
configuration, it’s recommended that you use the variants()
function instead of the config function.
Don’t use the config function to look up variants
addUtilities(newUtilities, config('variants.customPlugin'))
Use the variants function instead
addUtilities(newUtilities, variants('customPlugin'))
Since variants
could simply be a global list of variants to configure for every plugin in the whole project, using the variants()
function lets you easily respect the user’s configuration without reimplementing that logic yourself.
// tailwind.config.js
const plugin = require('tailwindcss/plugin')
module.exports = {
variants: ['responsive', 'hover', 'focus'],
plugins: [
plugin(function ({ config, variants }) {
config('variants.customPlugin')
// => undefined
variants('customPlugin')
// => ['reponsive', 'hover', 'focus']
})
]
}
Exposing options
It often makes sense for a plugin to expose its own options that the user can configure to customize the plugin’s behavior.
The best way to accomplish this is to claim your own key in the user’s theme
and variants
configuration and ask them to provide any options there so you can access them with the theme
and variants
functions.
For example, here’s a plugin (extracted to its own module) for creating simple gradient utilities that accepts the gradients and variants to generate as options:
// ./plugins/gradients.js
const _ = require('lodash')
const plugin = require('tailwindcss/plugin')
module.exports = plugin(function({ addUtilities, e, theme, variants }) {
const gradients = theme('gradients', {})
const gradientVariants = variants('gradients', [])
const utilities = _.map(gradients, ([start, end], name) => ({
[`.${e(`bg-gradient-${name}`)}`]: {
backgroundImage: `linear-gradient(to right, ${start}, ${end})`
}
}))
addUtilities(utilities, gradientVariants)
})
To use it, you’d require
it in your plugins list, specifying your configuration under the gradients
key in both theme
and variants
:
// tailwind.config.js
module.exports = {
theme: {
gradients: theme => ({
'blue-green': [theme('colors.blue.500'), theme('colors.green.500')],
'purple-blue': [theme('colors.purple.500'), theme('colors.blue.500')],
// ...
})
},
variants: {
gradients: ['responsive', 'hover'],
},
plugins: [
require('./plugins/gradients')
],
}
Providing default options
To provide default theme
and variants
options for your plugin, pass a second argument to Tailwind’s plugin
function that includes your defaults:
// ./plugins/gradients.js
const _ = require('lodash')
const plugin = require('tailwindcss/plugin')
module.exports = plugin(function({ addUtilities, e, theme, variants }) {
// ...
}, {
theme: {
gradients: theme => ({
'blue-green': [theme('colors.blue.500'), theme('colors.green.500')],
'purple-blue': [theme('colors.purple.500'), theme('colors.blue.500')],
// ...
})
},
variants: {
gradients: ['responsive', 'hover'],
}
})
This object is just another Tailwind configuration object and has all of the same properties and features as the config object you’re used to working with in tailwind.config.js
.
By providing your defaults this way, end users will be able to override and extend your defaults the same way they can with Tailwind’s built-in styles.
CSS-in-JS syntax
Each of addUtilities
, addComponents
, and addBase
expect CSS rules written as JavaScript objects. Tailwind uses the same sort of syntax you might recognize from CSS-in-JS libraries like Emotion, and is powered by postcss-js under the hood.
Consider this simple CSS rule:
.card {
background-color: #fff;
border-radius: .25rem;
box-shadow: 0 2px 4px rgba(0,0,0,0.2);
}
Translating this to a CSS-in-JS object would look like this:
addComponents({
'.card': {
'background-color': '#fff',
'border-radius': '.25rem',
'box-shadow': '0 2px 4px rgba(0,0,0,0.2)',
}
})
For convenience, property names can also be written in camelCase and will be automatically translated to dash-case:
addComponents({
'.card': {
backgroundColor: '#fff',
borderRadius: '.25rem',
boxShadow: '0 2px 4px rgba(0,0,0,0.2)',
}
})
Nesting is also supported (powered by postcss-nested), using the same syntax you might be familiar with from Sass or Less:
addComponents({
'.card': {
backgroundColor: '#fff',
borderRadius: '.25rem',
boxShadow: '0 2px 4px rgba(0,0,0,0.2)',
'&:hover': {
boxShadow: '0 10px 15px rgba(0,0,0,0.2)',
},
'@media (min-width: 500px)': {
borderRadius: '.5rem',
}
}
})
Multiple rules can be defined in the same object:
addComponents({
'.btn': {
padding: '.5rem 1rem',
borderRadius: '.25rem',
fontWeight: '600',
},
'.btn-blue': {
backgroundColor: '#3490dc',
color: '#fff',
'&:hover': {
backgroundColor: '#2779bd'
},
},
'.btn-red': {
backgroundColor: '#e3342f',
color: '#fff',
'&:hover': {
backgroundColor: '#cc1f1a'
},
},
})
…or as an array of objects in case you need to repeat the same key:
addComponents([
{
'@media (min-width: 500px)': {
// ...
}
},
{
'@media (min-width: 500px)': {
// ...
}
},
{
'@media (min-width: 500px)': {
// ...
}
},
])
Adding variants
The addVariant
function allows you to register your own custom variants that can be used just like the built-in hover, focus, active, etc. variants.
To add a new variant, call the addVariant
function, passing in the name of your custom variant, and a callback that modifies the affected CSS rules as needed.
const plugin = require('tailwindcss/plugin')
module.exports = {
plugins: [
plugin(function({ addVariant, e }) {
addVariant('disabled', ({ modifySelectors, separator }) => {
modifySelectors(({ className }) => {
return `.${e(`disabled${separator}${className}`)}:disabled`
})
})
})
]
}
The callback receives an object that can be destructured into the following parts:
modifySelectors
, a helper function to simplify adding basic variantsseparator
, the user’s configured separator stringcontainer
, a PostCSS Container containing all of the rules the variant is being applied to, for creating complex variants
Basic variants
If you want to add a simple variant that only needs to change the selector, use the modifySelectors
helper.
The modifySelectors
helper accepts a function that receives an object that can be destructured into the following parts:
selector
, the complete unmodified selector for the current ruleclassName
, the class name of the current rule with the leading dot removed
The function you pass to modifySelectors
should simply return the modified selector.
For example, a first-child
variant plugin could be written like this:
// tailwind.config.js
const plugin = require('tailwindcss/plugin')
module.exports = {
plugins: [
plugin(function({ addVariant, e }) {
addVariant('first-child', ({ modifySelectors, separator }) => {
modifySelectors(({ className }) => {
return `.${e(`first-child${separator}${className}`)}:first-child`
})
})
})
]
}
Complex variants
If you need to do anything beyond simply modifying selectors (like changing the actual rule declarations, or wrapping the rules in another at-rule), you’ll need to use the container
instance.
Using the container
instance, you can traverse all of the rules within a given module or @variants
block and manipulate them however you like using the standard PostCSS API.
For example, this plugin creates an important
version of each affected utility by prepending the class with an exclamation mark and modifying each declaration to be important
:
// tailwind.config.js
const plugin = require('tailwindcss/plugin')
module.exports = {
plugins: [
plugin(function({ addVariant }) {
addVariant('important', ({ container }) => {
container.walkRules(rule => {
rule.selector = `.\\!${rule.selector.slice(1)}`
rule.walkDecls(decl => {
decl.important = true
})
})
})
})
]
}
This plugin takes all of the rules inside the container, wraps them in a @supports (display: grid)
at-rule, and prefixes each rule with supports-grid
:
// tailwind.config.js
const plugin = require('tailwindcss/plugin')
module.exports = {
plugins: [
plugin(function({ addVariant, e, postcss }) {
addVariant('supports-grid', ({ container, separator }) => {
const supportsRule = postcss.atRule({ name: 'supports', params: '(display: grid)' })
supportsRule.append(container.nodes)
container.append(supportsRule)
supportsRule.walkRules(rule => {
rule.selector = `.${e(`supports-grid${separator}${rule.selector.slice(1)}`)}`
})
})
})
]
}
To learn more about working with PostCSS directly, check out the PostCSS API documentation.
Using custom variants
Using custom variants is no different than using Tailwind’s built-in variants.
To use custom variants with Tailwind’s core plugins, add them to the variants
section of your config file:
// tailwind.config.js
modules.exports = {
variants: {
borderWidths: ['responsive', 'hover', 'focus', 'first-child', 'disabled'],
}
}
To use custom variants with custom utilities in your own CSS, use the variants at-rule:
@variants hover, first-child {
.bg-cover-image {
background-image: url('/path/to/image.jpg');
}
}