I'm running an [OpenStick](https://github.com/OpenStick/OpenStick) next to my Kubernetes cluster for fun and there's actually a lot of useful software that runs great with a limited amount of ram.

Some of my favourites are:

[Zeroclaw](https://github.com/zeroclaw-labs/zeroclaw) - 3 MB RSS when idle!

[Beszel](https://github.com/henrygd/beszel) - 10 MB agent + 10 MB server

[Gatus](https://github.com/TwiN/gatus) - 10 MB

[Fusion RSS](https://github.com/0x2E/fusion) - 22 MB

[Adguard Home](https://github.com/AdguardTeam/AdGuardHome/) - 40 MB

[Shiori](https://github.com/go-shiori/shiori) - 10 MB

You won't be able to run all of this on a 128 MB ram VPS but I bet you can run 1-2 services easily!