Skip to content
A CircleCI Plugin for posting bundle diffs to your GitHub PRs.
Branch: master
Clone or download
Fetching latest commit…
Cannot retrieve the latest commit at this time.
Type Name Latest commit message Commit time
Failed to load latest commit information.


Separate the wheat from the chaff in your static asset bundles

A CI integration for tracking file size changes across builds. Pluggable for different CI providers. (Currently plugins only exist for CircleCI.)

What it Does

At its core, thresh does four things:

  1. Outputs file sizes of assets targeted by your thresh config. (Where and how these are output depends on the artifactStore plugin you use.)
  2. If current bulid is associated with an existing PR, posts commit status. This status will be success if there are no assets which violate size thresholds defined in your thresh config, failure if there are assets which violate sizes thresholds, and error if any errors were encountered. The contents of this status will contain asset diffs if they could be calculated.

CLI Options


  • Description: Filepath to your thresh conifg file.
  • Type: String
  • Default: ./.threshrc.toml


Create threshrc.toml File (Documented in JSDoc Format)

  • {string} thresholds - A list of configuration objects used to determine the conditions under which the GitHub status will be posted as "failed."
    • {(string|string[])} thresholds.targets - The target(s) of the threshold. Each target can be either a file path or a glob.
    • {string} thresholds.maxSize
  • {string} [artifactStore = '@danny-andrews/thresh-artifact-store-circleci'] - The module name of the artifact store plugin you want to use. Defaults to CircleCI.
  • {string} [ciAdapter = '@danny-andrews/thresh-ci-adapter-circleci'] - The module name of the CI adapter you want to use. Defaults to CircleCI.
Example config file:
targets = "dist/app.js"
maxSize = 20000
strategy = "total"

This example would post a failed GitHub status if the total size of all javascript assets was larger than 20kB.

Define Environment Variables

    • Must have read access to repository (public_repo scope for public repos, and repo scope for private repos)
    • Must have repo:status scope

Comparison with Other Offerings

bundlesize buildsize thresh
Handles Fingerprinting? Y Y Y
Posts PR Status Filesize Diffs? Y Y Y
Relies on 3rd-party service? Y Y N
CIs Supported Travis CI, CircleCI, Wercker, and Drone Circle CI Circle CI, easy to add more
Configuration Expose GitHub access token to environment None Expose GitHub/CircleCI access token to environment

Writing plugins

ciAdapter Plugins

A valid thresh ci adapter is just a function which returns an object with methods with the following signatures:

isRunning :: () => Boolean
getEnvVars :: () => {
  buildSha: String,
  buildUrl: String,
  artifactsDirectory: String,
  repoOwner: String,
  repoName: String,
  pullRequestId: Maybe[String]

artifactStore Plugins

A valid thresh artifactStore is just a function with the following signature:

() => {
  getAssetStats: (baseBranch = String, assetStatsFilepath = String) -> ReaderPromise[AssetStat]

Future Plans

Creating more integrations for different CI environments.

You can’t perform that action at this time.