How do I know if my update caused a regression?

Compare the new version against the previous one and watch for newly-broken things. The clearest sign is the new build crashing more than the version it replaced, a regression makes the new version worse, so per-version comparison showing a higher crash rate (or more errors) on the new build means it regressed. Also watch for a new crash signature appearing after the release (a failure mode your previous builds never had, almost certainly introduced by the update), and a previously-working feature now broken (a regression is by definition something that worked before now broken, often with complaints about something that 'used to work'). To see these, monitor per version: per-version crash tracking shows the new build against the previous one (revealing if it's worse), catches new signatures on the new build, and surfaces the regression fast. The key insight is that a regression is the update making something worse, so the way to detect it is comparison, comparing the new version's crash rate, signatures, and feature behavior against the previous build, which isolates what the update changed for the worse, whereas an aggregate that blends versions would hide the regression.

Why do updates cause regressions in features I didn't touch?

Because changes ripple through shared dependencies. A fix or feature you add in one place often touches code, data, or state that other systems rely on, so a change made for one purpose can quietly break a feature elsewhere that depended on the same function, value, or behavior, producing a regression in code you never directly edited. Games are especially prone because systems are interconnected, shared managers, global state, common utilities, so a change's effects spread further than you intended. It's also easy to verify a change narrowly (confirming the thing you meant to change works) while not re-checking the features that could be affected downstream, so the regression in the untouched-seeming feature ships unnoticed. This is exactly why regression testing covers your core flows broadly (not just the area you changed) and why testing the ripple areas a change could affect matters, the regression is usually not in your change itself but in something downstream of it. It's also why a new crash signature after an update often points at code you didn't mean to touch: the update's ripple effect broke something elsewhere. The practical implication is that you can't assume a change is isolated just because you intended it to be; changes have ripple effects through shared code, so updates can break features you didn't directly modify, which is why detecting regressions requires checking the whole game's behavior (not just your change) and why per-version monitoring is valuable, when a regression does slip into untouched-seeming code, it shows up as the new build performing worse or a new crash signature, so you catch it even though you didn't anticipate which feature the change would break.

How can I catch regressions before players do?

Run a regression pass before shipping and monitor per version after, so you catch regressions both before they reach players and right after if any slip through. Before shipping, run a regression check over your core flows, not just the area you changed (since regressions hide in the ripple effects, in features you didn't directly touch), verifying that the things that worked before still work, a short checklist of must-work core flows plus automated tests catches the catastrophic regressions in minutes. This catches many regressions before players hit them. But testing can't catch everything (you can't exhaustively test every feature and condition), so after shipping, monitor per version: compare the new build's crash rate against the previous one (a regression shows as the new build being worse), watch for new crash signatures (newly-introduced failures), and alert on spikes (so a regression that slipped through is caught in minutes as the new build's numbers diverge from the old). This catches the regressions that escaped testing, fast, while they've affected few players and can still be rolled back or hotfixed. So you catch regressions before players by running a pre-ship regression pass over your core flows (preventing the ones you can catch), and you catch the ones that slip through right after release via per-version monitoring (so even the escaped regressions are caught fast, before they spread to most players). The combination, regression testing before shipping plus per-version monitoring after, covers regressions on both sides of release, which is what keeps a shipped regression from quietly degrading your game until players complain. The key is that you can't rely on testing alone (some regressions slip through), so pairing it with per-version monitoring ensures you catch regressions fast even when they escape your pre-ship checks, ideally before most players hit them.

Signs Your Update Introduced a Regression

Quick answer: Watch for the new version crashing more than the last, new crash signatures after release, a previously-working feature now broken, and complaints about something that used to work. A regression is the update making something worse.

A regression, an update breaking something that worked before, degrades your game silently if you're not watching for it. Here are the signs your update introduced a regression.

The New Version Crashing More Than the Previous One

The clearest sign is per-version comparison: the new build with a higher crash rate than the version it replaced. A regression makes the new version worse, so if you compare the new build against the previous one and the crash rate is up, the update regressed. Without comparison, this hides in the overall noise.

Bugnet tracks crash rate per version, so comparing the new build against the last is direct. The new version crashing more than the previous one is the definitive sign of a regression, and per-version comparison is what makes it visible, since it isolates exactly the question of whether the update made things worse.

A New Crash Signature Appearing After the Release

Regressions often show up as a new crash signature, a failure mode your previous builds never had. So a sign is a new signature appearing right after the update: a crash that didn't exist before and does after is almost certainly a regression the update introduced, often in code you didn't mean to change.

Bugnet groups crashes by signature and tracks per version, so a new signature on the new build stands out. A new crash signature appearing after a release is a strong sign of a regression, catching the ones that introduce new failures, and it often points at code you didn't intend to touch, since regressions hide in the ripple effects of changes.

A Previously-Working Feature Now Broken

A regression is, by definition, something that worked before now broken, so a direct sign is a feature behaving incorrectly after an update when it was fine before, often accompanied by complaints about something that used to work. If players report that a feature broke after the update, you've likely shipped a regression.

Bugnet captures bugs and errors from the field, so a newly-broken feature surfaces. A previously-working feature now broken, especially with players noting it worked before the update, is the most direct sign of a regression, and it confirms that the change rippled further than intended into something it shouldn't have affected.

Watch for the new version crashing more than the last, new crash signatures after release, a previously-working feature now broken, and complaints about something that used to work. A regression is the update making something worse.