docker-bitcoind VS umbrel-apps

Bitcoind https://hub.docker.com/r/lncm/bitcoind

Umbrel appears to use lncm/docker-bitcoind. My deployment simply named the container "bitcoin" so you should be able to interact with the container using docker exec as the umbrel user:

All official and/or popular Docker images. You can view individual Docker images for every app here: https://github.com/getumbrel/umbrel-apps

So on umbrel, there is a way to run local instance of Nextcloud that works out of the box. I have it set up in addition to the one with domain. Maybe check this link out https://github.com/getumbrel/umbrel-apps/blob/master/nextcloud/

I feel like you're not really answering OP's question, so I'll give it a go. From what I can tell Umbrel is essentially delivering compose file that is using Vaultwarden image behind the scenes.

Here is an example of someone that did exactly what you're asking for: https://github.com/getumbrel/umbrel-apps/blob/master/btcpay-server/docker-compose.yml

If you want your application to be integrated into Umbrel itself, you have to follow these instructions. Submitting it for inclusion into their app store is entirely optional.

First, I checked if there was any easy way to go about this through the Umbrel interface (/u/katarinamightytravel suggested that there was). I, like you, could not find it anywhere. I don't see anything listed on the list of apps that looks promising (https://github.com/getumbrel/umbrel-apps).

If you have a look at the docker-compose file for the Umbrel LNBits app you'll get a sense of how it works with your node. It's communicating with the LND back end over REST. Basically, it *is* your wallet, but with additional features layered on top, and with a level of abstraction that keeps funds separate. That unfortunately is the limit of my technical understanding, but the gist of it is that, because LNBits talks to the underlying LND service to get things done, sending funds from your Umbrel "wallet" to LNBits is basically sending funds to yourself.

I don't know about raspiblitz, but you can see exactly what docker images Umbrel is using for each app here: https://github.com/getumbrel/umbrel-apps

That's probably as simple as bumping the container version and submitting a PR on the umbrel apps repo.