react/create-react-app · critical · Error

Using `babel-preset-react-app` requires that you specify `NO

Error message

Using `babel-preset-react-app` requires that you specify `NODE_ENV` or `BABEL_ENV` environment variables. Valid values are "development", "test", and "production". Instead, received: ${JSON.stringify(env)}.

What it means

create.js derives isEnvDevelopment/isEnvProduction/isEnvTest by comparing the active Babel environment to the literal strings. If none match, the preset cannot decide which transforms to apply and aborts. The environment comes from BABEL_ENV, falling back to NODE_ENV, surfaced here as the `env` argument.

Source

Thrown at packages/babel-preset-react-app/create.js:58

    opts.typescript,
    true
  );
  var areHelpersEnabled = validateBoolOption('helpers', opts.helpers, true);
  var useAbsoluteRuntime = validateBoolOption(
    'absoluteRuntime',
    opts.absoluteRuntime,
    true
  );

  var absoluteRuntimePath = undefined;
  if (useAbsoluteRuntime) {
    absoluteRuntimePath = path.dirname(
      require.resolve('@babel/runtime/package.json')
    );
  }

  if (!isEnvDevelopment && !isEnvProduction && !isEnvTest) {
    throw new Error(
      'Using `babel-preset-react-app` requires that you specify `NODE_ENV` or ' +
        '`BABEL_ENV` environment variables. Valid values are "development", ' +
        '"test", and "production". Instead, received: ' +
        JSON.stringify(env) +
        '.'
    );
  }

  return {
    presets: [
      isEnvTest && [
        // ES features necessary for user's Node version
        require('@babel/preset-env').default,
        {
          targets: {
            node: 'current',
          },
        },

View on GitHub (pinned to 6254386531)

Solutions

1. Export NODE_ENV to one of development/test/production before invoking the toolchain: `NODE_ENV=development npm run <script>`.
2. Set BABEL_ENV explicitly if NODE_ENV must stay different: `BABEL_ENV=test`.
3. Add `cross-env NODE_ENV=development` (or test/production) to the relevant script in package.json for OS-portable behavior.
4. If running under Jest, ensure the test script or jest config sets NODE_ENV=test (react-scripts does this in scripts/test.js).

Example fix

// before
// package.json
"scripts": { "build:lib": "babel src --out-dir lib" }
// after
"scripts": { "build:lib": "cross-env NODE_ENV=production babel src --out-dir lib" }

// Validate the environment before Babel ever loads the preset.
const VALID_ENVS = ['development', 'test', 'production'];
function ensureBabelEnv() {
  const env = process.env.BABEL_ENV || process.env.NODE_ENV;
  if (!VALID_ENVS.includes(env)) {
    throw new Error(
      `Set NODE_ENV/BABEL_ENV to one of ${VALID_ENVS.join(', ')} (got: ${String(env)})`
    );
  }
  return env;
}
ensureBabelEnv();

const isKnownEnv = (e) =>
  e === 'development' || e === 'test' || e === 'production';

try {
  babel.transformFileSync(file, { presets: ['react-app'] });
} catch (e) {
  if (/NODE_ENV|BABEL_ENV/.test(e.message)) {
    console.error('Missing env. Run with NODE_ENV=development|test|production');
    process.exit(1);
  }
  throw e;
}

When it happens

Trigger: Loading babel-preset-react-app when BABEL_ENV/NODE_ENV is unset, empty string, or set to any value other than 'development', 'test', or 'production' (e.g. 'staging', 'ci'). The branch `!isEnvDevelopment && !isEnvProduction && !isEnvTest` is true and throws.

Common situations: Running Jest/Babel directly in a fresh shell without NODE_ENV. CI images that don't export NODE_ENV. Setting NODE_ENV to a custom stage name. Using the preset outside react-scripts (e.g. in a custom build) without replicating react-scripts' env setup.

Related errors

• Using `babel-preset-react-app` requires that you specify `NO
• Preset react-app: '${name}' option must be a boolean.
• Preset react-app: '${name}' option must be a boolean.
• The NODE_ENV environment variable is required but was not sp

AI-assisted analysis of react/create-react-app@6254386531 (2026-08-12). Data as JSON: /api/errors/d410c066e7d796c2. Report an issue: GitHub.