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This looks really cool, but at first glance it seems like you really need to already know how to create nix flakes and what all the settings mean to use the site. I didn't sign up, but I watched your redis video (https://www.youtube.com/watch?v=3fuCGXHw7qM) and it seems like you just knew all the configuration settings you wanted and searched for them.

Maybe that's fine for your target user, but I would think you could get non-nix folks on board if there was more of a "wizard" type flow that tells you the options and explains them as you go through it.

Good point! Additional wizard-style UIs will make sense for certain use-cases, such as e.g. "adding a new user", or "creating a Python environment". Another strategy is to keep making re-use and composition easier, as this is a great way of learning. By seeing what is necessary to set up a Docker image, simply copying the necessary settings and then tweaking the config to add your services should allow learning through trial and error.

Composition is already possible, where you can import modules between flakes, such that you can keep e.g. the Docker base config in one flake, then re-use this in other flakes. Soon, indexing of modules will also be added to the site, which will make it easy to import e.g. a base computer configuration from `nixos-hardware`: https://mynixos.com/nixos-hardware

Some other features which will be added is cloning of flakes, and easily copying + moving sets of settings between modules and flakes. This should also make it easier to borrow settings from other configurations to build your own.

Sounds great! I currently run a NixOS desktop but I still struggle quite a bit with the documentation and discoverability of configuration/language. That's one of the biggest pain points in my eyes, so a UI like you have could really make that simpler. Letting users introspect what settings are available and how they work seems like one way of making things more discoverable (but not necessarily making a specific wizard for a specific build, since that doesn't seem scalable or generalizable).

That said, I also agree with you that having reusable modules that are documented would help, and being able to clone and copy/paste settings + seeing examples would too. Good luck!

I find the options search to be generally suitable for that case https://search.nixos.org/options

Yeah that's super helpful for NixOS configuration options. What trips me up more is configuring particular packages. Usually it's where I want to configure a particular version or github commit of a package for some reason (usually I want a bug fix).

However, a bunch of packages are defined in some bespoke way with various custom config inputs that generate other bits of config and generally are hard to understand. Thinking it through, I'm not sure it's possible for the OP's tool to solve this particular problem.

1000% this. I spun up a nixos VM to play around and love the concept, especially things like declarative home directories.

But it’s impossible to discover all the various things you can do.

Does a nix language server improve discoverability?

I’ve read about Nix 10 times on HN and can’t figure out why I’d use it over Docker. I already know Docker + Compose and the syntax for Nix looks gross/confusing.

I am guessing Nix flake is like Dockerfile. You build it, and then what? How/where do you run it? k8s? Docker? Is it OCI?

Docker solves "distributing software is hard" by using container images; so you copy the container image, and running that will work consistently everywhere.

Nix solves "distributing software is hard" by ensuring declarations of packages can be built/run in a reproducible way.

Software built with Nix doesn't need to run in a container runtime (which is much nicer for desktop / workstations).

Nix's strength is dealing with packages in a programmatic way. This allows it to also serve as a package manager (like brew or pacman), as a way of declaring an OS configuration (in NixOS), it can also be used to build container images, or VM images.

Nix is badly named, because it is many things.

Nix is a lazy, functional programming language that was designed to write reproducible packages (in the traditional Linux distro sense).

A Nix package is just a function. It takes in some inputs (the dependencies), and produces an output. But instead of saying “take libssl”, you actually say “take libssl at this exact version” (or more precisely at this exact combination of input files with this exact content). However, because it is a programming language, you can make the package inputs generic over the version. This may seem esoteric and pointless but actually gives rise to a lot of nice properties (reproducibility, caching, recompilation tracking among others).

Nix Packages, are a collection of packages that are written using this language. It’s pretty comprehensive and many packages can be used on both Linux and Mac (like Homebrew), so it’s a cross-platform package manager. Unfortunately, the package manager for this set of packages is also called Nix.

NixOS is an operating system built on top of the language, using the packaging ecosystem (Nix Packages) and also providing some abstractions for writing services, declaring users, crons etc. (kind of like Ansible).

A Nix Flake is a relatively new thing. It is a framework on top of the Nix language for writing these {packages/OS config} that can much more cleanly specify the dependencies and pin them. Kind of like NPM, but for everything (package versions, OS module versions, any Git repo etc.). You could do this before, but it was less nice. Now, you can update all the dependencies of your entire project with one command, including things like shell plugins, Vim plugins, the version do Bash used to run your build scripts, developer tools, LSPs for your editor, your text editor itself (though I usually don’t go this far) etc.

There are many other uses. You can use it to build OCI images (they are just a specific way of combining some dependencies, and this can be expressed pretty easily in Nix). These have better properties than typical Docker images (built via Dockerfile) and can be cached better and tend to be smaller without needing to use something like musl. You can use it manage user dotfiles (similar to OS management, see Home Manager), developer environments (kind of like Python virtualenv, but for everything), project dependencies and whatever else you can build on top of the language really. Basically anything that could benefit from having packages nicely integrated with config could be built with/on top of Nix.

Why would you use it? Well for me:

* I like being able to manage package versions and config together painlessly, which was always a pain with Ansible.

* It’s fully declarative (if you remove the config for a service it stops running; not true for e.g. Ansible)

* Nix language is not the greatest, but it is sooo much better than YAML. Unfortunately the set of language features needed is quite niche, so it couldn’t just be a library for an existing popular language (except maybe Haskell or a Lisp)

* I like being able to update everything (with free rollbacks if something breaks) with 1 command.

* It’s pretty interesting. It’s theoretically quite well built and find ways to make good use of some nice programming constructs (e.g. fixed points, laziness), that appeals to me. What the language lacks is documentation and tooling.

* Reproducibility is nice, but not the selling point for me.

I dipped in my toes with using Nix Shell to have reproducible developer environments and then slowly moved everything over.

Could you help me understand how I'd migrate say... a Rust app with a Dockerfile running in Postgres glued together Docker Compose with Nix?

Thanks for the writeup by the way, it's appreciated and well done.

I get that NixOS is a Linux distro. What is Nix's answer for containers?

aka the typical Docker flow

Dockerfile -> build OCI image -> run it as a container

Nix package -> ? -> ?

There’s a few different levels of commitment, I’ll go through the just “dip your toes” variant to the fully commuted version:

* Use Nix shell for developer environment. Use it to provide a version of Docker, Rust, development Postgres etc. This is just a kind of virtualenv you activate after you cd into the project directory. You can manually manage the versions of the tooling for your project separately (if needed) and you don’t need to install these globally on your developer machine.

* Replace Dockerfile with a Nix package. This may be a bit trickier depending on how complicated the app is. You can build the rust app with Nix and then build a Docker image from the rust app and all other things you want in the container. You can do the same for Postgres (although there’s less point, since the Docker image is officially maintained). There’s no direct benefit to doing this (except maybe smaller images if you aren’t using e.g. alpine and maybe slightly better cacheability).

* Replace your base OS with NixOS. This is whatever you run the Docker containers on. You’d still use Docker containers and Docker compose, but the underlying OS would be NixOS, rather than Ubuntu/Debian/etc.

* Replace Docker containers with systemd services on NixOS. This is the hardest sell, but a lot of people use Docker just for versioning and providing dependencies, and you can just use Nix for that. So if you don’t need to use Docker for other things, you can just run apps on bare NixOS, using systemd configured with Nix (the language). That’s what using services on NixOS will do. You’ll basically be writing systemd services for your app (there is already going to be one provided by NixOS for Postgres) in the Nix language and running them directly on Linux. One thing that’s not easy to do with Docker Compose is cron jobs (for backups monitoring etc.). You can run these just as systemd timers. This also has some nice benefits (e.g. user isolation whereas Docker containers run as root, Unix sockets to avoid needing to bind ports and restrict access to certain users, no extra (runtime) layers on top of your OS, less complex networking).

To illustrate as examples on the Docker flow

Start: Docker, Rust etc. installed globally.

Dockerfile -> build OCI image -> run it as a container on Debian/whatever as distro

Stage 1: Docker, Rust etc. installed in a Nix Shell

Dockerfile -> build OCI image -> run it as a container on Debian/whatever as distro

Stage 2: Docker, Rust etc. installed in a Nix Shell

Nix package -> build OCI image with Nix -> run it as a container on Debian/whatever as distro

Stage 3 (can be done independently of 1 and 2): Docker, Rust etc. installed in a Nix Shell

Nix package -> build OCI image with Nix -> run it as a container on NixOS

Stage 4: Docker, Rust etc. installed in a Nix Shell

Nix package running as a systemd service managed by NixOS

I've tried to use Nix multiple times for things that it would be perfect for... I really want to use it (this is the 5th time I've given it a shot) ... and every time I put it down.

You've built a great tool here, seriously nice work!

... but you built it on an experimental feature that isn't enabled by default, that requires understanding the extensibility mechanisms to add experimental features that the Nix project doesn't feel comfortable calling done yet, that may change in future

... except everyone says flakes are totally stable and fine to use cause. Like basically everyone seems 100% fine with flakes... to the point where I've even come across first time Nix user tutorials that assumed you had already jumped through the hoops to enable an experimental feature a.k.a. "flakes" and this was several months ago.

But if flakes are so amazing and so stable everyone is using it and assuming everyone uses it and wants everyone to use it... after an entire year of wide public use ... why aren't they a stable feature yet, or even planned for release as a stable feature?

Once Nix can get this sorted, I'll probably be using it within a week. But I'm not comfortable diving in and making heavy use (I've played with Nix at every layer, from my macOS user as a homebrew alternative, to Docker/Container building, to running entire headless and desktop immutable OS installs on bare metal using NixOS) ... but for now its still an experimental feature so once again I'm putting Nix back in the "check it out again later next time HN gives me a good reason" drawer... I'm not going to rely on experimental features and I'm not going to learn and internalise how to do everything the hard way when flakes is obviously better (I did actually RTFM on all this), I just keep waiting for it to be blessed as stable.

Thank you for the feedback!

The site is built on the assumption that the flake interface is here to stay. The reason is simply because it is a very powerful, general, and pure interface. To simplify the installation process, the https://mynixos.com/install-nix install script makes sure to enable the necessary config to use flakes.

Hopefully the feature will be declared stable soon, and I totally get your feelings towards depending on experimental features.

> A few examples of what you can do right now

These examples look neat. I'm reminded of https://nix.dev/ (which, sadly, is pre-flake).

> make it easy to create and share Nix and NixOS configurations

I could see a lot of value in the sharing/reading aspect of this. -- I think it'd be helpful to be able to look at different NixOS configurations without having to dig into the code directly.

> The site works directly with the Nix command line tool

I find this part confusing.

One of the neat things about nix flakes, is that it's "like docker without containers". You can just run `nix run github:<owner>/<repo>`, and nix will be able to run the code from that flake. -- So I guess I'd expect the "copy-paste to run this" command to be similar to "nix run https://mynixos.com/<whatever>".

But, the "Download" section in the Meta tab of the demonstrations are about using some tool that isn't nix.

Thanks for the feedback! When released, the flakes are just tarballs which can be used with the Nix command line tool, for example

  nix develop https://api.mynixos.com/mynixos/demo-windows-devshell/archive/latest.tar.gz

Will bring you into the development shell declared by the demo-windows-devshell flake. You can either copy the link for specific versions, or use the "Latest" reference link. These links can either be used with the Nix command line tool or as direct flake input URLs to flakes that you write outside of MyNixOS.

Note that the commands shown in the "Meta" section are just shell scripts to help you install Nix, direnv, and a flake loader, which is just a convenience wrapper that you can keep in your source control if you wish.

Thanks for doing this! Nix has been one of those tools that looks so cool, yet the instruction manuals are akin to the "...draw the rest of the fuckin' owl" meme whenever I look into it. This gives me hope to give it another go!

That's really cool to hear! Please feel free to reach out on the Matrix chat if you get stuck anywhere: https://matrix.to/#/#mynixos:matrix.org

Looks great. Submit it to https://www.reddit.com/r/NixOS/ too, if you haven't already.

Thank you! There's been a couple of posts:

- https://www.reddit.com/r/NixOS/comments/wzqv2v/mynixos_alpha...

- https://www.reddit.com/r/NixOS/comments/ys0tad/mynixos_alpha...

Trying to not spam in order to keep the signal ratio decent, however this new set of tutorials might make sense to post :)

I think r/selfhosted would love this too

Thank you - I didn't know about that one! Created a post there now:

https://www.reddit.com/r/selfhosted/comments/z66yo9/mynixos_...

How does this differ from flox[1]? It looks like you're trying to cover much of the same ground.

[1] https://floxdev.com/

Flox's website was only opened up a few weeks ago, so it hasn't really factored into the development of MyNixOS. I haven't had the chance to test it yet, but I'd guess a few differences would be that Flox is targeting enterprise use with proprietary tooling + formats, with a larger focus on the command line interface, in order to guarantee the user experience to a larger degree. MyNixOS targets pure Nix flakes and the Nix command line tool, and focuses more on the website UX to lower the barrier for creating and sharing Nix flakes for beginners.

As the potential for the core Nix technology is so great, many different approaches and tools will be necessary to help discover and cover the different use-cases. Flox made a good impression at NixCon in Paris, and they seem to be doing a lot of good things to make the community solid.

hey, flox person here, thanks for the kind words :)

> many different approaches and tools will be necessary to help discover and cover the different use-cases

this -- we're very excited to see the many experiments going on in the "Nix UX space". The more the merrier. While we do see significant opportunity to solve problems for enterprise, we designed the core flox CLI for anyone to use. And of course it can work with any flake you provide, from MyNixOS or elsewhere...

Looking forward to making it more public soon :)

Awesome. After my arch configs blew up after the last major upgrade between September and March I thought to give nix another try. I ran it on macOS, first with nix-Darwin later only with home-manager and on Linux. I won’t try to manage macOS anymore. I’ll give this a try. Lucky for me I already spend a lot of time with nix and my hope is that this time around I get a better result.

Great to get some experienced people testing it out. Please feel free to reach out on Matrix if you get stuck anywhere or wish to provide feedback: https://matrix.to/#/#mynixos:matrix.org

I want to like Nix so badly but I just can’t get past the thought that it’s complete overkill.

By the time you get comfortable with the syntax and tooling, you could’ve just crafted use-case specific shell scripts to compile/configure everything from source…

It can be a bit of a challenge as it introduces many concepts at the same time, however it seems like many enjoy Nix once they get comfortable. Once the investment has been made, you also have a far more scalable setup than use-specific scripts.

Feel free to check out one of the MyNixOS demos - hopefully having a working starting point and being able to modify a config without writing Nix can make it easier for beginners.

Show HN: MyNixOS – Create and share Nix and NixOS configurations