Hi! We are really excited that you are interested in contributing to the Vue devtools. Before submitting your contribution, please make sure to take a moment and read through the following guide.


The repository is a monorepo with several nested packages:

apiThe public devtools API that can be installed in Vue plugins
app-backend-apiAbstract API to link the Public API, the core and Vue handlers
app-backend-coreThe main logic injected in the page to interact with Vue apps
app-backend-vue1Decoupled handlers to support Vue 1 (soon)
app-backend-vue2Decoupled handlers to support Vue 2
app-backend-vue3Decoupled handlers to support Vue 3
app-frontendVue app displayed in the browser devtools pane
shell-chromeChrome/Firefox extension
shell-electronElectron standalone app
shell-hostDevelopment environment
shell-dev-vue2Demo app for development (Vue 2)
shell-dev-vue3Demo app for development (Vue 3)


  1. Clone this repo
  2. Run yarn install in the repository root to install dependencies.
  3. Run yarn run build:watch (compiles and watch the packages) and then yarn run dev:vue3 (run the development shell) in two different terminals. Wait for the initial compilation in the first terminal to finish before running the second command.
  4. A plain shell with a test app will be available at http://localhost:8090.

Pull Request Guidelines

Thank you for your code contribution! Before opening a PR, please make sure to read the following:

  • Checkout a topic branch from a base branch, e.g. main, and merge back against that branch. For example: feat/my-new-feature.

  • Please make sure that you allow maintainers to push changes to your branch when you create your PR.

  • If adding a new feature:

    • Provide a convincing reason to add this feature. Ideally, you should open a suggestion issue first and have it approved before working on it.
  • If fixing bug:

    • If you are resolving a special issue, add (fix #xxxx[,#xxxx]) (#xxxx is the issue id) in your PR title for a better release log, e.g. fix: update entities encoding/decoding (fix #3899).
    • Provide a detailed description of the bug in the PR. Live demo preferred.
  • It's OK to have multiple small commits as you work on the PR - GitHub can automatically squash them before merging.

Running tests

  1. Run yarn lint to check code quality with ESLint.
  2. Run yarn test to run all tests. (@TODO)

Testing as Chrome addon

This is useful when you want to build the extension with the source repo to get not-yet-released features.

  1. Clone this repo
  2. cd devtools the newly created folder
  3. run yarn install
  4. then run yarn run build:watch & yarn run dev:chrome in parallel
  5. Open the Chrome extension page (currently under Menu > More Tools > Extensions)
  6. Check "developer mode" on the top-right corner
  7. Click the "load unpacked" button on the left, and choose the folder: devtools/packages/shell-chrome/ (it will have an orange disk icon)
  8. Make sure you disable all other versions of the extension

Testing as Firefox addon

  1. Install web-ext
$ yarn global add web-ext

Also, make sure PATH is set up. Something like this in ~/.bash_profile:

$ PATH=$PATH:$(yarn global bin)
  1. Clone this repo
  2. run yarn install
  3. then run yarn run build:watch and yarn run dev:chrome in parallel
  4. run yarn run:firefox

Docs development

  1. Clone this repo
  2. cd devtools the newly created folder
  3. run yarn install
  4. run docs:dev