Plugin options

Options go in a wombatail: { ... } object passed to createBabelPlugins, or directly to the plugin if you wire Babel up yourself. Explicit options always override wombatail.config.*.

Option	Type	Default	Description
configFile	boolean | string	search upward from the Babel root	false disables config lookup, a string points at an explicit file, true requires one to exist.
breakpoints	string[]	from the config file	Breakpoint names accepted as class prefixes.
mergeFunctions	string[]	['cn', 'clsx', 'cx', 'twMerge']	Compile-time class merge function names.
failOnUnsupported	boolean	true	Throw for unsupported classes instead of dropping them.
allowUnknownThemeColors	boolean	true, or false when a config file supplies tokens	Allow any semantic bg-/text-/border-/tint- token to map to theme.colors.
themeColorTokens	string[]	from the config file	Allow-list of semantic theme color tokens (camelCase). Required when allowUnknownThemeColors is false.
allowJsxSpread	boolean	false	Allow JSX spread on an element that also has className.
evaluateConstBindings	boolean	true	Evaluate const bindings containing statically analyzable class expressions.
debug	boolean	false	Build-time diagnostics.

createBabelPlugins

babel.config.js

const { createBabelPlugins } = require('babel-plugin-wombatail/babel-config')

module.exports = function (api) {
  api.cache(true)
  return {
    presets: ['babel-preset-expo'],
    plugins: createBabelPlugins({
      wombatail: {
        // only to override wombatail.config.ts
        allowJsxSpread: false,
      },
      unistyles: {
        root: 'src',
        // autoProcessPaths / autoProcessImports for monorepos
      },
      // React Compiler / worklets / reanimated, in the order those tools require
      after: [],
    }),
  }
}

The helper guarantees Wombatail runs before the Unistyles plugin. Entries in after are appended, so React Compiler still lands after Unistyles as Unistyles requires.

Production-safe defaults

• failOnUnsupported: true — typos and unimplemented features fail the build.
• allowJsxSpread: false — avoids unknowable precedence from runtime spread objects.
• allowUnknownThemeColors flips to false automatically when a config file supplies theme color tokens.

Programmatic API

The plugin module also exposes helpers used by the compiler and tests:

const wombatail = require('babel-plugin-wombatail')

wombatail.resolveClassName(className, options)
wombatail.resolveUtility(token, options)
wombatail.normalizeOptions(options)
wombatail.withConfigFile(options, { root, filename })