What is it?
Roblox FFlag Watcher is a web app and server that watches and displays FFlag changes.
What is a Fast Flag (FFlag)?
The Roblox engine uses a system called Fast Flags as part of its deployment process. When code is shipped, not all of it is active by default. Rather, the changes are suppressed by flags that are dynamically enabled and disabled, even after the code is live on production.
Why should I care?
Sometimes, when a part of your game stops working without you changing anything, the reason is actually that a FFlag was changed since you last tested. Since Roblox changes these flags throughout the day, it’s possible that a newly enabled change will break something in your game.
I’ve personally wasted too much time trying to figure out why my code stopped working without me touching it, only to find out hours later that a recently changed FFlag was the root cause of the problem.
Next time you find yourself in a similar scenario when your code inexplicably stops working, checking against the FFlag tracker history can potentially save you time and help you give Roblox more useful information so that the root problem can be addressed more quickly.
Each FFlag has its own comment section next to its history where anybody can provide information, speculate, or link relevant DevForum posts. Here’s an example. I don’t expect people to comment all that often, but the option is there at least.
Thanks for checking out my latest project. I hope you find it useful and that it saves you time! If you have any suggestions or feedback, feel free to let me know with a reply or a GitHub issue.