Bug Reporting for Games with User-Generated Content

Games with user-generated content, level editors, creation tools, sharing, hand players the power to build, and with it the power to create bugs. A UGC game faces crashes and problems from content the developer never made or tested, content that exploits an edge case in your engine, that is malformed, or that simply does something you never anticipated, and because content is shared, one bad creation can crash many other players. Tracking UGC bugs means capturing which content was involved and separating your engine and editor bugs from issues in specific user content, so you fix the right thing.

UGC means bugs from content you never tested

The defining challenge of a UGC game is that players create content you never made or tested, and that content can trigger bugs you never anticipated. A user-built level that exploits an edge case in your physics, a creation that uses your tools in an unintended combination, malformed content that breaks your loader, all produce crashes and problems rooted in content outside your control, much like mods. Your engine must be robust to content you did not author and cannot fully predict.

Worse, UGC is typically shared, so a single problematic creation can affect many players who load it, turning one bad creation into a widespread crash. This amplifies the impact of UGC-triggered bugs and makes capturing the content involved essential. Tracking UGC bugs means accepting that your players will create content that breaks your game in ways you did not foresee, and building your bug tracking to capture which content was involved so you can understand and address these creation-triggered problems.

Separate engine bugs from content issues

The crucial distinction in UGC bug tracking is between bugs in your engine and editor, which you fix, and problems in specific user content, which may be the creator issue or may indicate your engine should handle that content more robustly. A crash triggered by user content might be an engine bug, your engine should not crash on that content, or a content issue, the content is malformed or abusive, and telling them apart determines your response.

Capture which content was involved and enough context to attribute the bug: a crash that occurs across many different creations points at an engine bug, while one specific to a single creation points at that content, possibly exploiting an engine weakness. This attribution, like separating modded from vanilla crashes, lets you focus on making your engine robust to the content players create, which is usually the right response, since a UGC game engine should not crash on user content even if that content is unusual or malformed.

Capture the content involved

For UGC bugs, capture which content was involved, an identifier for the creation, level, or item, and ideally enough of the content or its relevant properties to understand what triggered the bug. When a crash occurs loading or playing a creation, knowing which creation lets you examine it, reproduce the bug by loading it yourself, and see what about it triggered the problem.

Because content is shared and identified, capturing the content identifier lets you find the specific problematic creation, which is powerful: you can load the exact content that crashed players, reproduce the bug deterministically, and see whether it is an engine weakness to fix or a content issue to handle. This is more tractable than mod tracking in some ways, since the content lives in your system and you can retrieve it. The content context is what turns a UGC-triggered crash into a reproducible bug you can load and examine.

Make your engine robust to bad content

The most important response to UGC bugs is usually to make your engine robust to bad content, since you cannot control what players create, but you can control how your engine handles it. A UGC engine should validate and sanitize content, handle malformed or edge-case creations gracefully, and never crash on user content, even content designed to break it, which players will inevitably attempt.

Use your captured UGC crashes to find where your engine is not robust, the content patterns that trigger crashes, and harden the engine against them, validating inputs, handling edge cases, sandboxing risky operations. Because a bad creation can crash many players, this robustness is essential for protecting your community from each other content. The goal is an engine that handles any user content gracefully, and your captured UGC bugs are the data that shows you exactly where your engine fails to do so, guiding the hardening that keeps a UGC game stable despite unpredictable content.

Setting it up with Bugnet

Add a custom field for the content identifier and attach the content context on UGC-related crashes and reports, so you can see which creation was involved and separate engine bugs from content issues. Bugnet stores this alongside the crash, letting you filter to UGC crashes, attribute them, and find the specific content that triggered a problem.

Group crashes into occurrence counts and look at the content context to find whether a crash spans many creations, indicating an engine bug, or concentrates on specific content, and which creations are crashing players. Because UGC means bugs from content you never tested, and shared content can crash many players, this content-aware capture is what lets you reproduce UGC-triggered crashes by loading the involved content, harden your engine against the patterns that break it, and handle problematic content, keeping your UGC game stable despite the unpredictable creations players make.

Moderate and handle problematic content

Some UGC bugs are not engine weaknesses but genuinely problematic content, content designed to crash or abuse, or content that violates your rules, and handling it is part of running a UGC game. Use your captured data, showing which content crashes players, to identify problematic creations for moderation, removing or flagging content that harms other players, alongside hardening your engine against it.

This dual response, hardening the engine and moderating content, is how you manage the reality that UGC includes both well-meaning creations that happen to trigger bugs and occasional malicious content. The captured content context supports both, telling you which content to harden against and which to moderate. Communicating clear content rules to your community, and using your bug data to enforce them and protect players from harmful creations, keeps a UGC game healthy, balancing the creative freedom that makes UGC valuable with the stability and safety that shared content requires.

UGC means bugs from content you never made. Capture which creation broke, and harden the engine against it.