Build Runner Helper

Build Runner Helper runs build_runner for your Flutter and Dart projects from one click in the status bar — no copying long terminal commands, no guessing flags.

Perfect when you use Freezed, Riverpod, json_serializable, Retrofit, go_router, or any package that needs code generation.

Works in Visual Studio Code, Cursor, VSCodium, and other editors that support VS Code extensions.

Install

Open Extensions, search Build Runner Helper, and install.

What problem does it solve?

build_runner commands are long and easy to get wrong, for example:

fvm flutter pub run build_runner build --delete-conflicting-outputs

You run them many times a day after editing models, providers, or routes. This extension:

• Puts every common action in the status bar
• Runs commands in a dedicated Build Runner terminal
• Can target only the files that have errors in the Problems panel (faster than a full rebuild)
• Shows a spinning icon while a build or watch is active
• Lets you choose FVM, flutter pub run, or dart run in settings

How to use it

1. Open your project root folder (the one that contains pubspec.yaml).
2. Find Build Runner on the bottom status bar (left side by default).
3. Click it to open the menu.
4. Choose what you want to run.

While a command is running, the status bar icon spins. For a one-time build, it stops when the terminal command finishes. For watch, it keeps spinning until you stop it with Ctrl+C in the terminal.

Hover the status bar item to see status (Idle / Running) and your last command.

Everything the extension can do

Full project build

Runs a one-time codegen for the entire project.

Use when:

• You changed pubspec.yaml or build.yaml
• Many areas of the app changed
• A scoped build did not generate everything you need
• You want a clean full regeneration

Runs with --delete-conflicting-outputs by default (can be turned off in settings).

Full project watch

Runs continuous codegen for the entire project. Stays active until you stop it.

Use when:

• You are actively developing and want .g.dart / .freezed.dart files updated as you save

You may be asked to confirm before watch starts (setting: Confirm full watch).

To stop: open the Build Runner terminal and press Ctrl+C.

Build for error files

Looks at the Problems panel, finds Dart files with Errors under lib/ (and optionally test/), groups them by folder, and runs one scoped build with the right --build-filter paths — so only those areas are rebuilt.

Use when:

• You see red errors on generated files (.g.dart, .freezed.dart, etc.)
• You fixed source files and only need codegen for files that still show errors
• You want a faster build than full project

Example: errors in lib/features/shop/models/ → build_runner runs with a filter like lib/features/shop/models/**.

If there are no Dart errors under lib/, the extension tells you and does not run a command.

Watch for error files

Same idea as Build for error files, but in watch mode for those scoped folders only.

Use when:

• You are fixing errors in one feature and want codegen to update automatically for that scope only

You may be asked to confirm before watch starts. Stop with Ctrl+C in the Build Runner terminal.

Help

Opens a short in-editor guide (commands, settings, how to stop watch).

About

Shows the extension version, developer, and compatibility note.

Status bar

You can move the item to the right side of the status bar or hide the text label in settings.

If build_runner is already running

Before starting another job, the extension may warn you that build_runner is already running. You can:

• Show terminal — jump to the running session
• Run anyway — start another command
• Cancel — do nothing

Requirements

• A Flutter or Dart project with pubspec.yaml in the workspace
• build_runner (and your generators) added to the project
• fvm, flutter, or dart working in the integrated terminal

The extension only appears when your workspace contains pubspec.yaml.

Settings

Open Settings (Ctrl+,) and search Build Runner Helper.

Custom error filter mappings (advanced)

Only needed for unusual folder layouts. Example in settings JSON:

"buildrunnerHelper.errorFilterMappings": [
  {
    "pathPrefix": "lib/features/shop/",
    "buildFilter": "lib/features/shop/**"
  }
]

Troubleshooting

Feedback and support

• Report a bug or request a feature
• Discussions

Build Runner Helper · by Shafir K