How to Fix Godot Headless Test Runs Failing in CI

A CI agent has no display, so Godot must run headless, and the GUT runner must exit with a status code. Getting both right makes the suite pass or fail cleanly.

How to fix it

1. Run with the headless driver

Launch with godot --headless (4.x) so it uses the dummy display server and audio driver, which lets it run on an agent with no GPU or display.

2. Use GUT's CLI runner with exit

Invoke gut_cmdln.gd (or -s addons/gut/gut_cmdln.gd) with -gexit and configure it to set a nonzero exit code on failures so CI reports red correctly.

3. Point it at the config

Pass -gconfig=.gutconfig.json so the headless run uses the same directories and options as your local runs, avoiding the surprise of zero tests collected in CI.

Catching the ones you can't reproduce

The hardest version of this to fix is the one you can't reproduce — it only happens on a player's hardware, OS, driver, or save state, under conditions that simply aren't present on your machine. A report that says “it crashed” or “it froze” gives you nothing to act on, so the bug survives release after release while quietly costing you players.

Automatic error capture closes that gap. Each failure arrives with its full stack trace, the device and OS, the build number, and a breadcrumb trail of what the player did right before it broke, so even a failure you have never seen becomes a specific, reproducible issue. Fold identical failures into one signature ranked by how many players each hits, and your worklist sorts itself worst-first instead of arriving as a stream of vague complaints.

This is where a tool like Bugnet earns its place. Its SDK captures every Godot error automatically with the full stack trace plus device, OS, memory, build, and game-state context, folds duplicates into one grouped issue with an occurrence count, and ties each to the build it first appeared on — so you fix the problem that hurts the most players first and confirm it is gone when its signature disappears from the next release.