Diagnosing your upload failure

When Waldo rejects your upload

During onboarding, you are presented with a screen inviting you to upload a build of your app for the first time.


When you attempt to upload your first build to Waldo, Waldo performs a series of validation checks to ensure that your build is correctly constructed.

It can’t catch everything in advance (yet), but it does detect many common mistakes.

Two common issues we see are related to the following:

  1. Waldo expects that your build is made for Simulators
  2. We currently support builds made on x86_64 architecture at this time
  3. Your build must be compatible with the current, default device on Waldo

Each of these issues should be flagged as the cause of an upload failure, in a banner that will appear if the upload fails.

Once you get past the initial validation, Waldo performs some deeper validation checks.

When an error happens, the instruction modal will open with an error banner to help you understand what went wrong.


We also created a series of step-by-step videos to help you build your app.

The following error occurs in the rare case where there is not enough space available in your application’s binary header for Waldo to prepare for running on a (simulator) device. We suggest adding the following line to your Xcode build settings:

OTHER_LDFLAGS = -headerpad_max_install_names

Creating your build again in Xcode with this setting enabled nearly always alleviates the problem.

Once you have corrected all identified problems with your build, you can upload it to Waldo successfully, and then create your first test!