gatsbyjs/gatsby · critical

${err}

Error message

${err}

What it means

This error occurs during standalone engine regeneration -- a dev-only script that re-bundles the GraphQL query engine and page-SSR bundle after a successful gatsby build. The panic propagates any webpack bundling failure from createGraphqlEngineBundle or createPageSSRBundle (e.g. syntax errors, missing modules, webpack config issues). It is fatal: it terminates the regeneration process.

Source

Thrown at packages/gatsby/src/schema/graphql-engine/standalone-regenerate.ts:68

  // recompile
  const buildActivityTimer = reporter.activityTimer(
    `(Re)Building Rendering Engines`
  )
  try {
    buildActivityTimer.start()
    await Promise.all([
      createGraphqlEngineBundle(process.cwd(), reporter, true),
      createPageSSRBundle({
        rootDir: process.cwd(),
        components: store.getState().components,
        staticQueriesByTemplate: state.staticQueriesByTemplate,
        webpackCompilationHash: state.webpackCompilationHash, // we set webpackCompilationHash above
        reporter,
        isVerbose: state.program.verbose,
      }),
    ])
  } catch (err) {
    buildActivityTimer.panic(err)
  } finally {
    buildActivityTimer.end()
  }

  await validateEnginesWithActivity(process.cwd())

  reporter.info(`Rebuilding Rendering Engines finished`)
}

run()

View on GitHub (pinned to 8b06340921)

Solutions

1. Run a full `gatsby clean` then `gatsby build` to regenerate .cache and the initial bundles from scratch before re-running standalone-regenerate.
2. Inspect the inner `err` object in the panic output -- it contains the webpack error (module not found, syntax error, etc.); fix the underlying source issue.
3. Ensure all dependencies are installed (npm install or yarn) and that Node version matches the one used for the original build.
4. Delete .cache/webpack/query-engine and .cache/webpack/page-ssr manually and re-run the script.

// Before running standalone-regenerate, verify a prior build exists
const fs = require('fs-extra')
const hasPriorBuild = await fs.pathExists('.cache/webpack') && await fs.pathExists('public')
if (!hasPriorBuild) {
  console.error('Run `gatsby build` first to warm up the cache')
  process.exit(1)
}

// Wrap the regeneration invocation and surface webpack errors
try {
  await import('gatsby/dist/schema/graphql-engine/standalone-regenerate')
} catch (err) {
  console.error('Engine regeneration failed:', err.message)
  // The inner err has the webpack-specific failure details
  process.exit(1)
}

When it happens

Trigger: Running `node node_modules/gatsby/dist/schema/graphql-engine/standalone-regenerate.js` when the project has a webpack-breaking change in source files, a missing dependency, or a stale/incomplete .cache from a prior build on a different platform/arch.

Common situations: Developer edited a GraphQL plugin or page component with a syntax error then ran standalone-regenerate. Cache corruption after switching Node versions or OS. A required node module was removed from node_modules but is still referenced by the engine bundle entry.

Related errors

• It appears like Gatsby is misconfigured. JSONStore is Gatsby
• something changed in webpack but I don't know what
• Encountered unknown module type: ${module.type}. Please open
• 12200
• Could not find the file specified in the Link header `${head

AI-assisted analysis of gatsbyjs/gatsby@8b06340921 (2026-08-13). Data as JSON: /api/errors/16d6344a3b5832cc. Report an issue: GitHub.