Some tech I keep an eye on or research. My github starred repositories have a more complete list.
eBPF programs as a linux kernel sandbox has runtime guaruntees and privileges make for good observability tools. Combined with containers, eBPF programs have interesting capabilities in modern infrastructure.
Progressive Web Apps / Assembly / Sockets
Really like what web assembly brings to the web. Add websockets and progressive web app (PWA) services, I can see a lot of potential.
The Linux namespace additions to the kernel have proved extremely useful. Containerization solutions like Docker, Podman, LXC, or Kata Containers make deployments and testing highly reproducible. As a lightweight alternative to virtual machines, they effectively reshaped the world of shared infrastructure.
Selfhosted and IaaS
Intrastructure as a service has a lot of interesting self-hosted options. It may cost you for a better VPS setup but you could probably run a lot more.
Keybase has a nice solution for managing encryption (can always access your PGP key). I personally yubikey for services that support it. Try to sign git commits on projects when I can.
Artificial Intelligence / Machine Learning
An interesting area to be understandably excited about. The consumer/developer frameworks are simple and useful enough. The math and training new models is a bit complicated. I worry about security and the importance of data privacy.
Will probably get one at some point, it is the only mobile platform I have not worked on. They happen to make great secure laptops with open source hardware too.