Vend [1] and Movio [2] are two companies I know of that use Go. I know people in both companies and they've got a friendly culture.

I believe Centrality (blockchain company) and Soul Machines use Python.

You'll see a lot more NodeJS in the startups. Someone from Xero might be able to correct me here, but I've heard from friends at Xero that they're exploring Rust atm.

[1] https://www.vendhq.com/

[2] https://movio.co/

[3] https://centrality.ai/

[4] https://www.soulmachines.com/