Sometimes a developer may have a change to fix a bug, and the user who submitted the bug may not be in a position to build Wireshark from source to test the fix; see, for example, recent comments on bug 12845:
https://bugs.wireshark.org/bugzilla/show_bug.cgi?id=12845#c55
"The change hasn't been merged yet so there are no automated builds that have it included.
You would have to make your own build, applying the change first."
https://bugs.wireshark.org/bugzilla/show_bug.cgi?id=12845#c56
"That's unfortunately beyond my capabilities. Can you or Tomasz send me an installer (or just the binary if there are no external dependencies) of a version with this patch included to test whether it solves the issue? It might still be less work than creating the test extcap executable responding with my device lists."
Would it be possible to have an option in Gerrit to request a Petri dish build that builds the Windows installer and saves it somewhere such as
https://{download site}/download/petri/win32
with either 1) a maximum number to store there, 2) a timeout so that a given installer is only there for N days, or 3) an option to remove it, so that users not in a position to build from source can test it? Perhaps the installers should have names such as
Wireshark-win64-3.1.0-{change number}.exe
to make it clearer which build to get (and with a new build for a given change overwriting the previous build).
This wouldn't help for users with 32-bit Windows or with macOS, as we don't have 32-bit Windows or macOS Petri dish builders, but, if that matters, that could be the next step.