Balancing Focus and Fatigue as a Full-Time Developer

Lately, I’ve been thinking a lot about what it means to code full-time.
It’s not about disliking it - I really enjoy learning and building things - but I often struggle to stay focused for such long stretches.
My productivity usually peaks in the morning, but that’s also when most meetings happen. Like, right in the middle of my flow. By the time they’re done, my brain’s already half drained.
After lunch, my focus drops even more. I try to push through, but I’m not as sharp anymore.
There are topics I’d love to explore more deeply, but once the official workday ends, my energy is gone. So they just pile up.
I’m really curious how others deal with this.
If you’re a full-time dev:
How do you manage breaks and still get your hours in?
And what do you do when your brain just refuses to cooperate anymore?