[mdcds]

> The interviewers expressed a wish to see me go more in depth on technologies, but I simply don't have much experience in any of them

I conduct system design interview sessions for my org. My advice is to find opportunities to work on new architectures that use pieces of infrastructure that you aren't familiar with yet. You need to know the moving parts before you can start thinking about how you'd approach designing Twitter. Theoretical knowledge can be sufficient some times, but nothing beats hands-on experience.

How to get opportunities for hands-on experience in your case?! Idk, depends on your circumstances. Maybe go for an internal transfer to work on something different. Maybe go for a less senior role and but be picky about the new tech stack. Maybe go to a less prestigious company that pays less, but offers opportunities to build new skills.

Are you trying to go for ML Engineer or SDE positions?