NixOS Nix announcements, 14 Mar 2022

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From YouTube: What's new in Nix 2.7.0?

Description

An overview of changes in Nix 2.7.0.

https://discourse.nixos.org/t/nix-2-7-0-released/18072

Chapters:
00:00 Intro
00:14 Welcome
00:34 Bug fixes and performance
02:15 Changes in flake.nix format
06:50 Extended nix bundle support
09:30 Command line suggestions
10:05 nix store ping verbosity
11:10 sourcehut flake input type
12:18 nix profile remove verbosity
13:03 Final comments
13:28 Outro

A

Hi, I'm rogarbas.

B

And I'm tom bradley we're from the knicks marketing team would like to welcome you to the knicks 2.7 release overview. This is the second in a series of nyx release, notes, videos. I hope.

A

You will find this visual walkthrough, informative and worth your time. As always, feedback is appreciated in the comments below or by contacting the next marketing.

B

Team nix 2.7 is an incremental release of the nyx package manager on a six-week release cycle. There are many bug fixes and some new features being added. Many of the changes are related to experimental feature called flakes and we are to help stabilize and fix bugs in preparation for an ultimate 3.0 release.

B

This particular release has about 70 issues and 75 prs that were closed during its the release cycle. First up is performance.

B

Penne has done quite a bit of work, improving the performance over the last few cycles, and this is a quick summary of that work. We can see that we have the nyx releases on the bottom, starting from uh 2.3.16 all the way to some 2.7, as well as a pr being merged being labeled here as 2.8 pre release.

B

As you can see, uh there are some initial performance regressions uh up until 2.4 and even into 2.5, but we've been steadily been able to get some of these numbers back down, let's zoom in a little bit to take a little bit closer look at the section uh in progress, and you can see that this is for a nick's evaluation and again that initial performance degradation and then subsequent uh improvement.

B

As we've gone up to this current release and the potential uh future performance gains, we have, along with the pr 6218, giving us another 10 to 20 percent. The cpu um performance improvement usually goes hand in hand also with memory improvements of somewhat equivalent magnitude.

A

Next, we're going to look at the changes to the flake.next format. As you can see, I already installed nyx270, but before we continue, let's check uh if flake feature is a built on our system. We do this by looking at the nyxnxconfig and there you go experimental features, nick's command and fleet flakes. Are there first, let's look at nyx templates.

A

Let's do this by creating an example flake projects using the next like new command, then specifying the template. Let's say in this case: let's use the full template and give it a name sample there we go. uh There two features, two additions to the uh that were added into seven zero uh already shown. First, we are listing all the files that were created and after that we are displaying some sort of welcome text that is defined in each template.

A

If we look at the example, if you look at this template, you will see that this template consists of two files which are flake nicks and flake flick clock. And if you look at the definition of a template.

A

There we go and there we go. You will see here. We have a welcome text definition that should let everybody every author of templates to guide the users of a template to the let's say, documentation or other resources that a user might find useful. Okay.

A

So now, let's enter the template and we look at another uh change that happened uh in flake template. Let's first make sure that the log file is up to date.

A

There we go, log file is up to date and the next feature can be seen. If we run a nics flake check there we go, it will take some time, but you can already see that some deprecation warnings are being displayed five in total.

A

These deprecation warnings are about the default output.

A

Default, outputs and you can see if you're familiar with flake.mix and how the defaults are being were being.

A

Defined you will see that there are. You will know that there are many inconsistencies and this is an effort to bring some sort of order and unification uh in the in the flake.next.

A

So if we look at, let's say the over, uh let's say the default template right: let's, let's try to fix it, so we go to the flag.nick, so the default template is deprecated and please use templates.default there we go. I think this is at the end exactly so. First we change the default template and we say template dot default. So that's now the the that's still the same default and we also need to change all the reference to this default, template template and default.

A

Now, if we rerun nick's flick checked again, we should have one less deprecation warning there we go so, as you can see, maybe it's obvious, but we didn't break any changes with when introdu when doing this flake dot next change, so you can still continue to use old default flake output, but I suggest moving to the new ones, uh yeah and uh yeah. But if you wanna know exactly the changes for all the outputs uh that were changed, please consult the the nix manual.

B

The next change is to the bundler system. First off, what is a bundler? A bundler is going to take a derivation and transform it into something else, usually a self-extracting executable or a docker image, or some sort of standalone artifact.

B

What can this look like? This is where you take some sort of a installable and you can just bundle it or you can define a particular bundler that would you like to specify and use and transform your derivation using that? So, let's go take a look at how this actually looks like in practice.

B

We can take something like a normal hello package and say we want to bundle it to something called an ark's executable. What we end up with is a link to this thing and when we run this thing, it is going to extract itself to temp and is is now runnable. This allows you to run this on nearly any linux system that has certain features enabled and certain utilities available, but we can go even farther. We can also produce a docker image.

B

This is using the bundlers2 docker image bundler and now we have a tarball, and this is your a standard powerball that can be brought into a docker load or any sort of container runtime. What else can we do? We can show reports and let's go take a look at now. What this one does.

B

This one simply provides a quick runtime report. This was provided by uh and matia a little while ago and provides what the dependencies are licenses and some of the maintainers. So you, by giving by working over a derivation, it could do something a little bit richer and inspect the derivation itself to provide reports or probably to provide other sorts of outputs.

B

We have similar sorts of bundlers already ready to be used to do, convert things into an rpm, so you can see now we have an rpm that should allow us to install this in red hat as well as something for turning things into a depth.

B

Now all these things are fairly nice and these extra bundlers are defined at a new repo called bundlers, where we are starting to collect these, the idea being that we could now improve the number of these things in the quality of them in a coordinated fashion, and these will be available to people in a somewhat default manner without them having to do too much, and so contributions are always welcome.

B

So thank you that wraps up the butlers.

A

Next feature that was added is that now nix displays a helpful suggestion when you mistype something in the comment line. For instance, if I would go- and I would type really fast and my I would have some fat fingers, I might mistype and type build you can see. If I press it, the nix will suggest.

A

The right command, so, if I do next build- and I want to install the hello world- but I only type one l- it will suggest a hello.

B

Our next feature is nyx pink. For this we have added a little more verbosity, so it's easier to tell when something has been successful so with the next 2.6.1.

B

If we try to ping a store, it is going to be successful, but you don't really get much feedback that it was successful. Now, if you ping a store, we end up getting a little bit more information that a about what the version is and where it is. This is going to be on standard error, so it should not impact any sort of scripts or anything like that. Let's go take a look at what happens if we make it something a little bit more uh realistic as a remote store.

B

So let's go to cache.nxos.org and same thing. We get a quick result and it is successful.

B

Now, let's see what the error looks like if we go somewhere else, looks like we have some error with it being resolved, and now we can go, take a look at something that does resolve but is not an actual store, so this should make a using next store ping a little bit easier. Next up we have the sourcehut input type in nix versions. If you try to use a sourcehead input type, it would fail. This is not something that was supported, but this was added in 2.7.

B

So now you should be able to use a sourcehead input type, which is just sourcehut colon, followed by the user organization, name followed by the repo name, and now we can see we have uh we're showing some random flake here.

B

This can uh is going to be a little bit nicer in terms of usage and also has some optimizations that we can start to utilize.

B

So now, let's also run this against uh some file that we have available to us. So we have a markdown file, we're going to run this program against and now let's go take a look at what actually happened. We had a file that had a output defined and what this program apparently does is it pulls that out and turns it into its own uh file by pulling up some of this things from the inside of the markdown anyway, this is us running something with the sourcehut input type.

A

And the last feature I think it's worth to mention is that a bit of ux was added to the next command line.

A

Let's say in your profile, you have.

A

Hello world a hello package installed, you can see it's listed here uh when you're uninstalling, it all removing it from the profile, um uh no confirmation of what is being removed or is there something removed was uh displayed, and in this case now with two seven zero uh yeah. We we are displaying uh that some something gets removed.

B

And that's the last feature for now. The next release is planned in the middle of april. For those of you in the u.s. We hope to have it done before. Taxes are due at least you'll have an exciting new next version to look forward to.

A

This release would not be possible without all the hard work done by the contributors. At the same time, we would also like to thank all the users for bug. Reports example of usages ideas and for making the nyx community a better place. Thank you see you next time.

A