Yes, without any docker, or with docker if you like
But really the point is not to use docker, you just write an additional configuration file for the service you want. It looks like docker-compose but shorter, and you already have everything preconfigured (db, users, storage, etc)
Docker is not safe if not ran rootless. With nixos you can write a docker-compose-like file for the service to be docker/podman/baremetal/VM/anything
This search is for nextcloud, you can not only install the app and specify the login and password, but specify things like installed apps, default files, themes, which reverse proxyto use, and whether use some rules/headers/filtering