[earless1]

You must accept that you will sound like a fool just for using this word. You can use it for anything you want to show satisfaction/approval for. React.js on fleek, eyebrows on fleek, uptime on fleek

[ohitsdom]

"Eyebrows on fleek" is definitely most popular, but "uptime on fleek" is now one of my favorite phrases and will be used liberally.