Nix flakes explained
ฝัง
- เผยแพร่เมื่อ 10 ก.พ. 2025
- Enabling flakes:
nixos.wiki/wik... - commands are here
Creating a flake:
$ nix flake init
Updating a flake:
$ nix flake update
Flake:
```
{
description = "my epic vims collection";
inputs = {
nixpkgs.url = "github:nixos/nixpkgs/nixos-unstable";
};
outputs = { self, nixpkgs }:
let
system = "x86_64-linux";
pkgs = nixpkgs.legacyPackages.${system};
in
{
bob =
pkgs.mkShell
{
buildInputs = [
pkgs.neovim
pkgs.vim
];
shellHook = ''
echo "hello mom"
'';
};
};
}
```
(yes, I know I could push it to github, but I'm extra lazy today)
If my arithmetic is correct, you said nix twenty-seven (27) times. You said flake twenty-four (24) times, although technically thirteen (13) of the twenty-four (24) times was in the plural form as flakes. Nix, flakes, and cookies... yummy. :-) Keep up the excellent work with Nix and NixOS, as some of us are learning along with your videos and they help a lot. Thank you.
Holy cow! I'm going to have to count tomorrow morning, because It's late where I live, and also I've improvised in some parts of the video. 🍪
Also, if you have run out of cookies to send me, no problem. As a cookie substitution, I would really appreciate trying to understand how I could get dGPU passthrough to a VM figured out on a laptop, which has an AMD iGPU, and an AMD dGPU. I would like to be able to use NixOS for the base operating system, which would use the AMD iGPU, and then passthrough the AMD dGPU to a Windows VM so that the kids can use the laptop for school, Roblox programming, and gaming. Let me know if you think that this would make a great video, and if not, no worries. Thank you.
@@Becoming-HumanI've actually managed to setup GPU pass through on NixOS on my Lenovo legion 5 amd + nvidia dgpu about 3 months ago. It was kind of easy on NixOS, because I didn't worry about blacklisting something important. Maybe I'll do a video about it later.
@@vimjoyer Yes please to this, although I have intel igpu and nvidia dgpu (optimus). I've installed kvm and also quickemu, but haven't had time to troubleshoot why quickget seems to be downloading the windows iso, but then I don't find it in my home directory... Yes I know I can get it manually.
🤣🤣🤣🤣
Just last night I was complaining to my friend how I couldn't find a simple explanation how to use flakes, and you posted a video a few hours later. Thank you!
I'm making these videos because I'm also frustrated by the lack of documentation.
This comment for the YT engagement algorithm: my Emacs bros would be mad at me watching content from someone called Vimjoyer, but I don't care. After having just gone though a painful Debian reinstall, I wondered if there was a better way. Nix might be it. Or it might be Guix (who knows?).
For the time being, I am grateful for these videos. You have a new subscriber!
Did you end up going with nixos?
@@Anonymous4045Yeah, there are many more examples to work from in comparison to Guix, and the community is larger.
Your video should be part of a "must watch" list for NixOS beginner tutorials. Thank you for your effort!
I had just recently decided that since my Nixos was already working, it probably wasn’t worth it to figure out the motivation behind nix flakes (which I really couldn’t grasp until I watched this video). Thanks, this really explained it.
Honestly probably the simplest most matter of fact intro to Flakes I've pulled up so far. Thank you for this!
That is the most useful flakes introduction I have ever seen, good job mate
Easily, hands down.
Your microphone is not terrible! You sound clear AF!
Clearest explanation/example of nix flakes I've seen so far. Thanks, really useful!
your channel is gold, i understand about flakes and nixOS more deeply, i hope that you can more videos talking NixOS and its environment.
I really appreciate your work VJ. The presentation is excellent - visually clear and painstaking. Seems like I'm not the only person who appreciates this.
I finally started to understand what’s Flake are with your video.
Now it’s time for some practice ❤
Practice makes perfect
Such a simple and to-the-point explanation! TYSM.
Thanks, I've always thought that Nix is some witchcraft that is difficult for plebeians to practice, but turns out that it was a huge fallacy. Nix is so simple. Wouldn't have cleared out my doubt without you, many thanks for this splendid video, cheers.
God bless! I'm trying to learn NixOS so I can install it on my system, and flakes were by far the hardest concept for me to learn, but this made it simple to understand. Thank you so much!
I see that the playlist already has a lot of videos, but im still going to comment to make TH-cam recommend this playlist to other users just it did to me:)
Finally, a good nix flake description! Thx
Loving the content, subbed and looking forward to more as I just discovered nix!
Great series so far! You have a knack for explaining this stuff.
Thank you for the video! I hope your channel gets more known
Thanks for kind words!
Very well explained. Your initial comment about being on the 3rd page of still holds true nearly a year later.
Good work, thank you! Please continue this series!
The best explanation of flakes I have seem
Glad you liked it!
Dude! Very nicely explained. Thanks
Thank you for the video!
Consider uploading it to the wiki or docs
I'm not satisfied with the quality enough for wiki or docs 😅
@@vimjoyer I'd say its better than what exists now. Thanks for the tutorial.
@@sabergo1I agree, better fall forward
this was a very good explanation thank you
Nix flakes are the monad of packaging formats
My major concern with flakes is that in today’s age keeping your system up to date with security fixes is paramount. I would want to run updates on all my flakes weekly in an automated fashion. I wish the cli had an easy option for that.
I think `system.autoUgrade` can work with flakes. Relevant discourse thread - discourse.nixos.org/t/best-practices-for-auto-upgrades-of-flake-enabled-nixos-systems/31255
Thank you!
Fine! I'll subscribe. I think adding "- what are nix flakes?" to the title or description might help with SEO. Which Nix seems to be avoiding.
Thanks for this video this was very helpful!
Keep the nix videos coming!
Great content, keep it up.
By far the best explanation of flakes out there! And I have been looking for a long time!
Thank you so much for the video
This was excellent!!
KEEP THEM COMING!
I'd appreciate it if you made a video explaining nix profile, home-manager and how wrapping configuration.nix in nix flake eliminates the need of updating nix-channel
Yes please, +1 for this^
Please keep making nix videos!
This helped understand it a bit more. I would love if you can show how to add the ability to install "unfree" packages using home manager and flakes. I've been searching and just can't figure it out.
Thank you for the video
Thx dude.
Really loved the bob example just to show how to do it with any variable. Although I'm curious if you could do "bob.default" so you don't have to use the "#" in the command or would it need to be the whole "devshells.bob.default". What if it was just "devShells.bob"? Just curious since I'm just learning this.
Yeah, the convention is to have something.default, so it would be devshells.default
Thanks for a great intro to flakes! I'm not following what you mean with "if you named your dev shell bob ... you will have to use bob as key when running nix develop". What is a dev shell and how do you name it?
I want a cookie too ;-)
Thanks, very interesting. Something I'm confused about is what do you do if you want to upgrade to the latest stable version of a package or even update the lot? I get the idea of fixing versions but after a while we need to update as versions are no longer supported with bug and security fixes.
Check the latest flakes video on the channel, it will answer your questions
At 1:59, you say that the import essentially makes the shell.nix not deterministically reproducible. But we can pin the nixpkgs by fetchTarBalling a specific version
Not sure if this always existed, or if it is a new feature. But anyway would it still be justified/reasonable to use nix flakes instead of the default nix shell ?
I guess the exporting a default package is a newer feature?
Very good video! What fonts you use at 0:40 and 1:25 to show the command?
Jetbrains mono
02:57 We can see that no nixpkgs input specified for the flake. But it somehow got used later in the outputs. Also flake.lock got those nixpkgs pinned to some revision. Tell me, guru, what revision is gonna be used in this case?
If inputs field is not specified, nix just assumes you want a single nixpkgs input. IIRC it uses "github:nixos/nixpkgs/nixpkgs-unstable" by default.
I'm about to hop on Nix
Epic
Could you do a video on making a proper FHS file-system inside of nix? Something that can help bridge the gap when the packages of another ecosystem are not fully supported on Nix, it seems like a FHS system is necessary.
You can use buildFHSEnv (I'll make a video about it sooner or later)
Is it possible for making videos to guide set up nix package manager in macos, setting up nix flakes, home manager and the nix profile.
I am tired of reading blogs and 50/50 successful at setting up the above mentioned
Do you still recommend using Flakes today? Since they are still considered experimental?
yes
based, i will switch to nix from arch btw
you can use nix on arch no?
@deltamico yes but it's more limited, having only nixos installed is better, but the libertarian communist are ruining nixos, Arch is better
funny i start looking into nixos and this video just got uploaded recently
why one repo per flake? can i not have one repo for all flakes or is that a bad thing? (i have not yet started using nixos, I will first watch all your videos :)
I mean one flake for one separate project, you probably don't want your python project update break your rust development environment. Having 1 flake for both home-manager and NixOS on the other hand is a good idea.
@@vimjoyerok I understand! that makes sense
🎉
Thanks for the video, what i don't understand is (coming from Docker) where to store or mount persistent data. I'd like to mount an "host" directory where to keep important data outside the flake, is possible to do it?
I mean the equivalent of docker volumes
These development environments are not actually containers, they just modify some environment variables such as $PATH and $LD_LIBRARY_PATH to achieve what you see. They don't have their own storage, and you can access all your data. Flakes are just a way to declare those environments.
That being said, you can build your docker images with nix: nixos.wiki/wiki/Docker
You could use flakes to declare those as well.
@@vimjoyer thanks now i understand
sorry, i didn't get know what the power in flake ,and i was try to put My H-M in it ,it is not working ,btw nice video
So after this the vim command is still not available, what's the point.
Thanks for the inspiration, just started on a new clean refurbished laptop and installed nixos on wsl. Trying to get ohmyzsh to work declaratively with plugins. Trying to get home manager to work... What a rabbit hole.. hope to make it to the other side with and get reproducible pretty zsh env.
Anyone has a flake for that?? Thanks and all the best
Don't you call --zsh flag when running the command?
the video is pretty confusing and very hard to watch, this video is not zoomer friendly
sorry
maybe you shouldn't use nix?!
@@lennyescott why
Why is the volume so low?