Tilde, the company started by Yehuda Katz and Tom Dale of Ember fame, is building a product called Skylight. You can roughly think of it as a New Relic competitor.

It uses a Ruby extension written in Rust to collect the performance data.

For more details, check out this video from the Bay Area Rust Meetup: https://air.mozilla.org/sprocketnes-practical-systems-progra...