Brandur:
If you’ve ever run an app on Heroku, you may have come across log messages produced by the Heroku router and wondered about their untraditional formatting […]
This curious format is unofficially known as “logfmt”, and at Heroku we’ve adopted it as a standard to provide some consistency across internal components. […]
At its core, logfmt is just a basic way of displaying key/value pairs in such a way that its output is fairly easily readable by a human or a computer, while at the same time not being absolutely optimal for either.
Seems sensible to me.