[onionisafruit]

In the NixOS scenario you described, what keeps you from finding an unrelated thing stopped working three days later and having to find what changed?

I’m asking because you spoke to me when you said “because I'm simply not good at documenting my changes in parallel with making them”, and I want to understand if NixOS is something I should look into. There are all kinds of things like immich that I don’t use because I don’t want the personal tech debt of maintaining them.

[Scandiravian]

I think the sibling answer by oasisaimlessly is really good. I'd supplement it by saying that because you can have the entire configuration in a git repo, you can see what you've changed at what point in time

I'm the beginning I was doing one change, writing that change down in some log, then doing another change (this I'll mess up in about five minutes)

Now I'm creating a new commit, writing a description for it to help myself remember what I'm doing and then changing the Nix code. I can then review everything I've changed on the system by doing a simple diff. If something breaks I can look at my commit history and see every change I've ever made

It does still have some overhead in terms of keeping a clean commut history. I occasionally get distracted by other issues while working and I'll have to split the changes into two different commits, but I can do that after I've checked everything works, so it becomes a step at the end where I can focus fully on it instead of yet another thing I need to keep track of mentally

[Scandiravian]

I just realised I didn't answer the first question about what keeps me from discovering the issues earlier

The quick answer is complexity and the amount of energy I have, since I'm mostly working on my homelab after a full work day

Some things also don't run that often or I don't check up on them for some time. Like hardware acceleration for my jellyfin instance stopped working at some point because I was messing around with OpenCL and I messed up something with the Mesa drivers. Didn't discover it until I noticed the fans going ham due to the added workload

[maccard]

> because you can have the entire configuration in a git repo, you can see what you've changed at what point in time

That’s true of docker too.

[Scandiravian]

I'm not really sure what your point is, but I'll try to take it in good faith and read it as "why doesn't docker solve the problem for it, since you can also keep those configurations in a git repo?"

If any kind of apt upgrade or similar command is run in a dockerfile, it is no longer reproducible. Because of this it's necessary to keep track of which dockerfiles do that and keep track of when a build was performed; that's more out-of-band logging. With NixOS I will get the exact same system configuration if I build the same commit (barring some very exotic edge cases)

Besides that, docker still needs to run on a system, which must also be maintained, so Docker only partly addresses a subset of the issue

If Docker works for you and you're not facing any issues with such a setup, then that's great. NixOS is the best solution for me

[maccard]

That’s all my point was, yeah. Genuinely no extra snark intended.

> it is no longer reproducible

The problem I have with this is that most of the software I use isn’t reproducible, and reproducible isn’t something that is the be all and end all to me. If you want reproducible then yes nix is the only game in town, but if you want strong versioning with source controlled configuration, containers are 1000x easier and give you 95% of the benefit

> docker still needs to run on a system

This is a fair point but very little of that system impacts the app you’re running in a container, and if you’re regularly breaking running containers due to poking around in the host, you’re likely going to do it by running some similar command whether the OS wants you to do it or not.

[Scandiravian]

> if you want strong versioning with source controlled configuration, containers are 1000x easier and give you 95% of the benefit

For some I'm sure that's the case; it wasn't in my case.

I ran docker for several years before. First docker-compose, then docker swarm, finally Nomad.

Getting things running is pretty fast, but handling volumes, backups, upgrades of anything in the stack (OS, scheduler, containers, etc) broke something almost every time - doing an update to a new release of Ubuntu would pretty much always require backing up all the volumes and local state to external media, wiping the disk, installing the new version, and restoring from the backup

That's not to talk about getting things running after an issue. Because a lot of configuration can't be done through docker envs, it has to be done through the service. As a consequence that config is now state

I had an nvme fail on me six months ago. Recovering was as simple as swapping the drive, booting the install media, install the OS, and transfering the most recent backup before rebooting

Took about 1.5 hours and everything was back up and running without any issues

[oasisaimlessly]

Not OP, and not a very experienced with NixOS (I just use Nix for building containers), but roughly speaking:

* With NixOS, you define the configuration for the entire system in one or a couple .nix files that import each other.

* You can very easily put these .nix files under version control and follow a convention of never leaving the system in a state where you have uncommitted changes.

* See the NixOS/infra repo for an example of managing multiple machines' configurations in a single repo: https://github.com/NixOS/infra/blob/6fecd0f4442ca78ac2e4102c...

[maccard]

Both of those things are true of running containers, no?