windmill-labs/windmill · error

Build failed with errors

Error message

Build failed with errors

What it means

Post-build guard in createBundle: esbuild returned from build() without throwing, but result.errors is non-empty — esbuild reports some errors (e.g. unresolved imports, syntax errors in imported files) through the result object rather than as a thrown exception. Each error's text is logged to the console before this Error is thrown, so the terminal already shows the specific esbuild diagnostics; this throw converts the soft-failure into a hard stop so no half-built bundle is used.

Source

Thrown at cli/src/commands/app/bundle.ts:446

    // read anyway. Native esbuild supports write:false + outputFiles too.
    write: false as const,
    define: {
      "process.env.NODE_ENV": production ? '"production"' : '"development"',
    },
    plugins: [...frameworkPlugins, wmillPlugin, ...sharedUiPlugins],
  };

  log.info(colors.blue("📦 Building bundle..."));

  try {
    const result = await esbuild.build(buildOptions);

    if (result.errors.length > 0) {
      log.error(colors.red("❌ Build failed:"));
      result.errors.forEach((error: any) => {
        log.error(colors.red(error.text));
      });
      throw new Error("Build failed with errors");
    }

    log.info(colors.green("✅ Bundle created successfully"));

    const outputFiles = result.outputFiles ?? [];
    const jsFile = outputFiles.find((f) => f.path.endsWith(".js"));
    const cssFile = outputFiles.find((f) => f.path.endsWith(".css"));

    if (!jsFile) {
      throw new Error("Expected a JS bundle in esbuild output but none found");
    }

    try {
      fs.rmSync(distDir, { recursive: true });
    } catch {
      //ignore
    }
    return { js: jsFile.text, css: cssFile?.text ?? "" };

View on GitHub (pinned to e474e8803c)

Solutions

1. Scroll up to the '❌ Build failed:' block — each printed line is one esbuild error.text; fix those source/typing issues and re-bundle
2. For unresolved imports, ensure dependencies are in package.json and node_modules exists (the bundler can run npm install via ensureNodeModules)
3. For JSX/TS syntax errors, check the entry file extension matches the framework (tsx for React, ts for Svelte)

When it happens

Trigger: Thrown at cli/src/commands/app/bundle.ts:446 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of windmill-labs/windmill@e474e8803c (2026-09-03). Data as JSON: /api/errors/0ac197dcd4fea7d2. Report an issue: GitHub.