Private Sourcemaps

Private sourcemaps are a core feature available on all paid plans along with public sourcemaps.

This guide assumes you have already installed Airbrake in your JavaScript app.

Benefits of private sourcemap uploads

Uploading private sourcemaps to Airbrake:

  • Allows us to de-minify your JavaScript files and present your backtraces with meaningful line numbers that look like pre-minified source code
  • Provides a more accurate picture of the error and faster debugging times
  • Gives you all of the debugging benefits of publicly hosted sourcemaps without exposing your source code

Generating sourcemaps

Generating sourcemaps can be done with uglifyjs and webpack. Here is an example to minify and create a sourcemap for an app.js file:

uglifyjs app.js -o app.min.js -c -m \
  --source-map "root='',url=''"

This command will create two new files, a minified app.min.js file and a sourcemap named The sourcemap file is what we will be uploading to Airbrake.

Uploading sourcemaps

Continuing on with our above example, the next steps assume the minified version of app.js is publicly available at

The bottom of the app.min.js file should have a comment with the name of the of the sourcemap.


Upload your sourcemap

The following curl command assumes that your sourcemap file is in the current directory and will upload your sourcemap to airbrake.

curl \
  -X POST \
  -H 'Authorization: Bearer PROJECT_API_KEY' \
  -F \
  -F name="" \
  -F pattern="%/app.min.js"

Note: PROJECT_ID and PROJECT_API_KEY will need to be switched out for the real values from your project.

The optional pattern="%/app.min.js" is a SQL LIKE pattern and it tells Airbrake to apply the uploaded sourcemap to all files that match the pattern. An underscore (_) in pattern stands for (matches) any single character; a percent sign (%) matches any sequence of zero or more characters.

If pattern is not provided Airbrake will automatically generate one using file field from the uploaded sourcemap by prepending it with %/. For example, has file defined as airbrake.iife.js so the autogenerated pattern will be %/airbrake.iife.js. The same can be achieved with pattern="%/${file}". Useful patterns can be:

  • %/dist/${file} to match file in some folder.
  •${file} to match file on some domain.

Custom sourcemap URLs

If JavaScript file is not publicly accessible you need to manually associate the file and the sourcemap by providing a custom sourcemap URL.

Custom sourcemap URLs are supported by assigning a special property of notice.context called sourceMaps. The keys of the sourceMaps object represent shell filename patterns and the values are URLs of your sourcemaps.

airbrake.addFilter(function(notice) {
  notice.context.sourceMaps = {
    '': ''
  return notice;

Filename pattern uses Unix glob-like syntax:

  • * matches any sequence of non-path-separators
  • ** matches any sequence of characters, including path separators
  • ? matches any single non-path-separator character

For example:

airbrake.addFilter(function(notice) {
  notice.context.sourceMaps = {
    '**/app.min.js': ''
  return notice;

Viewing your uploaded sourcemaps

You can view a list of the sourcemaps that you’ve uploaded to Airbrake using this endpoint:

You can get your user auth token in your personal settings page. Results are returned according to our API’s pagination structure.


For your private sourcemap upload to function correctly it’s important you check that:

  • The name for the file should be fully qualified.
  • Your app.min.js file has the sourceMappingURL comment at the bottom of that file, e.g. //#

We also support public sourcemaps please visit our official airbrake-js repo for more info.

Sourcemap file size limit

Public and private sourcemaps have a file size limit of 32MB. Sourcemaps greater than 32MB will return a 400

{"code":400,"type":"Bad Request","message":"http: request body too large"}

Example of how Airbrake looks for your sourcemaps

  • Your project sends an error to Airbrake
  • Airbrake processes the error and sees a filename http://localhost:3000/javascript/app.js
  • Airbrake tries to download http://localhost:3000/javascript/app.js to extract sourcemap location, but it can’t since that file is on localhost
  • Airbrake then looks at notice.context["sourceMaps"] in case you manually associated a sourcemap with the http://localhost:3000/javascript/app.js file
  • From the sourceMaps value, Airbrake discovers that the sourcemap is located at http://localhost:3000/javascript/maps/, but Airbrake can’t download it since, again, it’s localhost
  • Airbrake then finally checks if you manually uploaded that file using this private sourcemap feature