So you installed the latest Android build to your device, and now wonder why Developer Options are gone from the settings menu?
Well it turns out Google decided to hide those options by default, and unlocking them kinda reminds me of software Easter eggs. So you have to open About Phone or About Tablet as in my case, scroll it all the way down until you see Build number entry. Now start tapping this line, and the system will tell you have many times are left. After pressing like 5 times, it will display a popup saying you have unlocked developer settings. My precious. Now if you want to hide it, open up Applications, then selected the ALL list, look for an app named Settings. Tap on it and select clear data, then agree to the warning. The settings will close, and when you open them back, the developer options will be hidden again.