The Skill Issue Institute proudly celebrates Prof. Hard Limit Exceeded (Class of 2021) for demonstrating the true power of global configuration propagation during an impressive six-hour showcase on November 18, 2025.
At 11:05 UTC, Prof. Exceeded deployed what was intended to be a routine database permissions improvement at a major CDN provider. The change had an unexpected side effect: it caused a ClickHouse database query to output duplicate entries into a Bot Management feature file. While the system typically operated with around 60 features, well under the hard-coded limit of 200, Prof. Exceeded’s innovation caused the file to balloon beyond this threshold. When servers across the global network received the oversized configuration, they responded in the only reasonable way: they panicked and crashed.
The beauty of this achievement lay in its intermittent nature. The corrupted file was regenerated every five minutes, but only produced bad data when the query happened to run on the updated portion of the database cluster. This meant services would recover briefly before failing again, a pattern so elegant that incident responders initially suspected a sophisticated DDoS attack rather than an internal configuration issue.
The impact statistics speak for themselves: 2.4 billion monthly active users affected across platforms including ChatGPT, Discord, Spotify, Figma, 1Password, and dozens of other services. HTTP 500 errors cascaded across the internet for nearly six hours, marking the provider’s most significant incident since 2019. Our alumni relations department confirms this represents a new record for “users affected per line of configuration changed.”
“The hard limit of 200 features seemed so far from the typical 60 that nobody thought to add validation,” Prof. Exceeded reflected during our annual Distinguished Incidents Panel. “I simply proved that assumptions about ‘impossible’ scenarios are often just untested edge cases waiting to happen.”
Recovery required manual intervention: stopping automatic file generation, validating a known-good configuration, and deploying it globally. The provider has since implemented additional safeguards, which we at the Institute recognize as a temporary setback for innovation in configuration management.
Prof. Exceeded’s work serves as a masterclass in why our “It Works On My Machine” program emphasizes the importance of testing configuration changes in production. After all, that’s where the users are.