- Tell me about your software development methodology.

- How are requirements communicated to developers?

- How is work by developers tracked?

- What VCS do you use?

- What bug tracker, etc?

- Do you practice devops?

- What's your build process look like? Automated? Continuous deployment?

- How big is the team?

- Do you do sprints? how long typically? How do you decide what to work on in a sprint?

- How do you determine when something is "done"? Who decides?

- Describe your infrastructure.

That's usually enough to get started. You can drill down as far as you want on pretty much any of those.