angular/angular-cli · error

The "dev-server" builder requires a target to be specified.

Error message

The "dev-server" builder requires a target to be specified.

What it means

The dev-server builder needs a target (project) to know which application to serve. If context.target is missing (no project name), it logs this error and returns EMPTY, so the dev server never starts. Unlike other paths this is an explicit error log rather than a thrown exception.

Source

Thrown at packages/angular_devkit/build_angular/src/builders/dev-server/builder.ts:60

  extensions?: {
    buildPlugins?: Plugin[];
    middleware?: ((
      req: http.IncomingMessage,
      res: http.ServerResponse,
      next: (err?: unknown) => void,
    ) => void)[];
    builderSelector?: (info: BuilderSelectorInfo, logger: BuilderContext['logger']) => string;
  },
): Observable<DevServerBuilderOutput> {
  // Determine project name from builder context target
  const projectName = context.target?.project;
  if (!projectName) {
    context.logger.error(`The "dev-server" builder requires a target to be specified.`);

    return EMPTY;
  }

  context.logger.warn(
    'The "@angular-devkit/build-angular:dev-server" builder is deprecated as part of Angular\'s Webpack support deprecation. ' +
      'Use "@angular/build:dev-server" instead. For more information, see https://angular.dev/tools/cli/build-system-migration.',
  );

  return defer(() => initialize(options, projectName, context, extensions?.builderSelector)).pipe(
    switchMap(({ builderName, normalizedOptions }) => {
      // Use vite-based development server for esbuild-based builds
      if (isEsbuildBased(builderName)) {
        if (transforms?.logging || transforms?.webpackConfiguration) {
          throw new Error(
            `The "application" and "browser-esbuild" builders do not support Webpack transforms.`,
          );
        }

        if (options.publicHost) {
          context.logger.warn(
            `The "publicHost" option will not be used because it is not supported by the "${builderName}" builder.`,
          );

View on GitHub (pinned to bb72145f9a)

Solutions

1. Run `ng serve <project-name>` explicitly naming the project.
2. Set `defaultProject`/`cli.defaultProject`-equivalent or ensure angular.json defines the project correctly.
3. When calling scheduleTarget programmatically, include a valid target: `{ project: 'app', target: 'serve' }`.

Example fix

// before
ng serve
// after
ng serve my-app

const projectName = context.target?.project;
if (!projectName) {
  throw new Error('dev-server requires a target: pass a project, e.g. ng serve <project>');
}

function hasTarget(c: { target?: { project?: string } }): c is { target: { project: string } } {
  return typeof c.target?.project === 'string' && c.target.project.length > 0;
}

When it happens

Trigger: Scheduling the dev-server builder without a target (e.g. architect.scheduleTarget({ target: ... } omitted or builder context lacking context.target.project), or `ng serve` run where the target cannot be resolved.

Common situations: Running `ng serve` outside a properly configured workspace; custom tooling calling the builder programmatically without specifying the project; corrupted angular.json missing the default project.

Related errors

• Unsupported package manager: "${name}"
• The configured package manager, '${this.descriptor.binary}',
• Project "${project}" does not exist.
• Project target does not exist.
• A builder is not set for target '${target}' in project '${pr

AI-assisted analysis of angular/angular-cli@bb72145f9a (2026-08-30). Data as JSON: /api/errors/35f7189537c0d857. Report an issue: GitHub.