Category: Uncategorized

Weekly News Summary for Admins — 2022-10-28

Release week! If this were a printed newsletter, it would be quite heavy: lots of links and posts, both from Apple and the MacAdmin community.

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I think it is fair to say that the Ventura beta and release has some challenges for system administrators. On the other hand, the updated Apple Platform Deployment guide and several support articles were ready on day one with lots of great information.

Many MacAdmins were awaiting the release and the end of the NDA and ready with several posts on topics they learned about during the beta. The most posts were on the new “Login and Background Items management” but several other posts on other new features and issues, as well. As always, thanks to everyone who shares their knowledge!

Aside from the major releases for macOS Ventura 13.0 and iPadOS 16.1, we also got iOS 16.1, watchOS 9.1, updates for tvOS, HomePod, the apps formerly known as iWork (Numbers, Keynote, and Pages), a new Xcode 14.1 RC, updates for Apple Business Essentials, Safari, macOS Monterey 12.6.1, Big Sur 11.7.1, and iPadOS and iOS 15.7.1. Also, the next round of updates for all the platforms is available in beta on AppleSeed for IT and for Developers, and we got a beta for the iCloud web interface.

Much to catch up on. I hope this collection of links and posts will help.

If you would rather get the weekly newsletter by email, you can subscribe to the Scripting OS X Weekly Newsletter here!! (Same content, delivered to your Inbox once a week.)

News and Opinion

macOS Ventura and iOS 16

macOS Ventura 13.0

iPadOS and iOS 16.1

watchOS 9.1

tvOS 16.1

HomePod Software

Services

Applications

User Guides

Apple Support

Reviews

Reactions and Posts

Login Items in Ventura

macOS and iOS Updates

Social Media

  • Mischa vd Bent: “Did you know about this nice feature with GitHub? Visual Studio Code is build into their website.”
  • John C. Welch: “One nice thing about MS (unlike Apple) having such detailed documentation about the powershell/VBA scripting implementation for Office, is that same model is the source for the AppleScript implementation, so you can use the PS/VBA docs to help you with AppleScript.”
  • Rosyna Keller: “In tons of places in macOS, including in Xcode’s log when notarization fails, there’s typically a “?” button in dialogs that if you click it, will bring you either to local or online documentation. In the notarization case, these buttons will take you to specific online docs.”

Security and Privacy

Support and HowTos

Scripting and Automation

Updates and Releases

To Listen

Support

If you are enjoying what you are reading here, please spread the word and recommend it to another Mac Admin!

If you want to support me and this website even further, then consider buying one (or all) of my books. It’s like a subscription fee, but you also get a useful book or two extra!

Weekly News Summary for Admins — 2022-10-14

Apple’s macOS Ventura Preview page still states “Coming this October.” The rumors, past experience and practicality point to October 24 as the release date for macOS Ventura 13.0 as well as iPadOS 16.1 and the first round of updates for iOS 16, watchOS 9 and all the others.

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On the other hand, Stage Manager still seems to be quite a mess in both iPadOS and macOS. Also, there was no announcement for an Apple Event on October 18, which you would expect if Apple wanted to announce new iPads Pro and/or a new Mac Pro to go with the iPadOS and macOS releases. Apple could very well release new hardware after the system releases, but it would be unusual.

The Mac Pro is the last Mac which has not transitioned to Apple Silicon yet and the two-year transition timeline, ,promised at WWDC 2020 with the Apple Silicon reveal expires in November, two years after the first M1 MacBooks shipped. The Mac mini, which is currently available as M1 and Intel models, also seems due for an upgrade.

We did get a new round of betas this week, which brings macOS 13 to beta 11. As a MacAdmin, you really should log in to AppleSeed for IT and read the beta notes that Apple makes available there, regarding software update deferral.

If you would rather get the weekly newsletter by email, you can subscribe to the Scripting OS X Weekly Newsletter here!! (Same content, delivered to your Inbox once a week.)

News and Opinion

macOS Ventura and iOS 16

macOS and iOS Updates

Social Media

  • William Smith: “As of Tuesday this week, version 16.66 of Microsoft Office for Mac was released and will be the last version to support macOS Catalina 10.15.”

Security and Privacy

Support and HowTos

Scripting and Automation

Updates and Releases

To Listen

Support

If you are enjoying what you are reading here, please spread the word and recommend it to another Mac Admin!

If you want to support me and this website even further, then consider buying one (or all) of my books. It’s like a subscription fee, but you also get a useful book or two extra!

Weekly News Summary for Admins — 2022-09-30

For me, this week was fully dominated by JamfNation User Conference (JNUC). It has been amazing and quite overwhelming to meet with all of you enthusiastic, smart, and inspiring Mac Admins!

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uberAgent is an innovative user experience monitoring product for macOS and Windows. uberAgent’s highlights include detailed information about application performance, network reliability drill-downs, application usage metering, browser performance, and web app metrics. Try for yourself and get your free 100 user community license at uberagent.com.

Jamf has been posting summaries of some sessions on the Jamf Blog. The sessions will be available for registered users (both virtual and in-person) in the conference portal for the next 60 days and then released for everybody on Jamf’s YouTube channel. I have a lot of catching up, and also a lot of re-viewing to do.

To everyone who took the time to talk with me, a huge thank you. All the kind feedback is both humbling and inspiring. To all who I missed or whom I couldn’t spend enough time with, because there was always the next engagement or meeting to run off to: I am terribly sorry! I hope we get a chance to talk at the next conference!

JNUC 2023 was announced for September 19–21 in Austin, Texas, USA.

(This news summary is unusually scheduled because of travel and time zones. I might also have missed some interesting links and posts. If you found something that I didn’t include, please let me know and I will include it next week.)

But the conference fun is not over: next week is MacSysAdmin Online and the speaker list was just released!

If you would rather get the weekly newsletter by email, you can subscribe to the Scripting OS X Weekly Newsletter here!! (Same content, delivered to your Inbox once a week.)

News and Opinion

macOS Ventura and iOS 16

Security and Privacy

Support and HowTos

Scripting and Automation

Apple Support

Updates and Releases

To Listen

Support

If you are enjoying what you are reading here, please spread the word and recommend it to another Mac Admin!

If you want to support me and this website even further, then consider buying one (or all) of my books. It’s like a subscription fee, but you also get a useful book or two extra!

Launching Scripts #1: From Terminal

Scripts, no matter which language they are written in, are an incredibly important part of a MacAdmin’s tool kit.

Most posts, books and tutorials focus on how to write scripts. Admittedly, the skill to make the computer and all its software running do what you want is very important. But once you have a working script, you will have to consider how to launch the script at the right time and with the right input.

When I started to think about this, I realized macOS provides many ways to launch or schedule scripts. Some are fairly obvious, others are quite obscure and maybe even frivolous.

Over the next few weeks (i.e. when I find time), I will publish a series of posts describing various ways of launching scripts and workflows on macOS. This post starts with the most obvious: launch a script from Terminal.

The Basics: Launch from Terminal

It might seem trivially obvious that you can launch scripts and workflows from Terminal. Nevertheless, it does require some explanation and context. Launching from Terminal is the most basic form of launching a script. As such, it defines the ‘baseline’ experience of how we expect scripts to run.

Command lookup

When you enter something into a Terminal prompt and hit the return key, the shell will split the text on whitespace. The first element of the text is the command. If that text contains a / character, the shell will interpret the entire element as a path to the executable. The path can be relative or absolute.

If the first element does not contain a / then the shell will first look for functions, aliases and built-in commands, in that order. Then the shell will search for a command executable using the colon-separated paths in the PATH environment variable. It will use the first executable it finds.

If the shell fails to find something to execute, it will show an error.

This is why you need to the ./ to execute scripts in the current working directory. Even though the ./ seems redundant, it tells the shell to look for the executable in the current working directory, instead of using the PATH.

You can find this process described in more detail here. I also have a post on how to configure your PATH variable.

Shebang

Scripts are ‘just’ text files. Two things distinguish them from normal text files.

First, the executable bit is set to tell the system this file contains executable code. You do this with the chmod +x my_script.sh command. Here comes the trick, though. The text in the script file isn’t really executable code that the CPU can understand directly. It needs an ‘interpreter’ which is another program that, wells, interprets the text file and can tell the CPU what to do.

The interpreter for a script file is set in the first line of the script with the #! character combination. The #! is also called ‘hashbang’ or ‘shebang.’ The shebang is followed by an absolute path to the interpreter, e.g. /bin/sh, /bin/bash, or /usr/local/bin/python.

Note: the shebang has to be in the very first line (actually the first characters) of the script, you cannot have comments (or anything else) before it.

Note: you often see shebangs using the env command in the form #!/usr/bin/env bash. These are useful for cross-platform portability, but have trade-offs. I have an article just for that.

Arguments

The shell is only interested in the first part of the command line text you entered. The entire list of parts (or elements, split on whitespace) are passed into the command as its arguments. A shell script sees the first element, the command or path to the command as $0 and the the remaining arguments as $1, $2, and so on.

Other languages will handle this in a similar fashion, arrays or lists of arguments are common.

Environment

Shells also have environment variables. We already talked about the role of the PATH variable in the command lookup. In Terminal, you can list all variables in your current environment with the env command. Some of these environment variables can be extremely useful, like SHELL, USER, and HOME.

When you launch a script from Terminal, a new shell environment is created and all of the environment variables are copied. This is great, beacuse the script can access the environment variables, and might even change them. But the changes in the script’s sub-shell, will not affect the current shell. In other words, a script can change the PATH environment variable in its own context, without changing yours.

In other Unix-based systems, environment variables are a common means of providing data to apps and processes. In the interactive shell on macOS, environment variables are very useful for this purpose. We will see, however, that when you launch processes and scripts through other means, environment variables can be a challenge on macOS.

Note: A shell environment also contains shell options, which are also inherited to sub shells.

Input and Output

Shell scripts and tools also have input and output. When you launch a script from the the Terminal, both output streams (Standard Output and Standard Error) are connected to the Terminal, so the output will be shown in the Terminal window.

When you use a script with pipes, then its Standard Input (stdin) will be connected to the previous tool’s Standard Out (stdout). The last script’s stdout and stderr will be shown in Terminal.

One thing that is special about interactive Terminal input and output, is that it happens while the script or tool is running. That means you can get live updates on the progress.

When we launch scripts in other contexts, their input and output may be buffered. This means that the system waits for the script or tool process to complete before piping its output to the next tool or to the process that called it. This is not something you usually have to worry about, but again it is something you should have in mind when running scripts in non-Terminal contexts.

Conclusion

While glaringly obvious, launching a script from Terminal does have some intricacies. This post sets a ‘baseline’ for how scripts work on macOS. In future installments, we will re-visit some of these topics, and the differences will become relevant when we launch scripts in contexts other than an interactive shell.

In the next post, learn how to create a double-clickable file to launch a script from Finder.

Weekly News Summary for Admins — 2022-03-25

After all the announcements of the last weeks, this week feels quieter. Something must be going in on Cupertino, as we have not gotten betas for macOS 12.4/iOS 15.4 yet. Maybe the developers have to start preparing their WWDC sessions.

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News and Opinion

Books

macOS and iOS Updates

MacAdmins on Twitter

  • Mr. Macintosh: “The Mac Studio has arrived! I’ll go over a few details others might not have covered” (Thread)

Security and Privacy

🔨Support and HowTos

Scripting and Automation

Apple Support

Updates and Releases

To Watch

To Listen

Support

If you are enjoying what you are reading here, please spread the word and recommend it to another Mac Admin!

If you want to support me and this website even further, then consider buying one (or all) of my books. It’s like a subscription fee, but you also get a useful book or two extra!

macOS Monterey 12.3 removes Python 2 – Link collection

Note: I will update this post for the next few weeks with new and updated information. If you find anything that is interesting, ping me on MacAdmins Slack or Twitter as @scriptingosx.

Last Updated: 2022-03-23

What is going on!?

Tools

Updates

  • dockutil: command line tool for managing dock items
  • quickpkg: wrapper for pkgbuild to quickly build simple packages from an installed app, a dmg or zip archive
  • Mist: A Mac command-line tool that automatically downloads macOS Installers/Firmwares
  • DownloadFullInstaller: macOS application written in SwiftUI that downloads installer pkgs for the Install macOS Big Sur application
  • SUS Inspector 2.1: Inspect Apple software update service
  • mkuser: Make user accounts for macOS with many advanced options

Replacing Python

Support

Installomator v8.0

We have published an update for Installomator. It is now at version 8.0 and has over 360 labels!

There were some bugs in the script that could make the script stall the Jamf agent, which prevented the client from checking back in with the Jamf server. This might affect other management systems as well. Please test behavior with the new version and report any issues that might remain.

The changes in detail:

  • removed leading 0 from the version because it has lost all meaning (thanks to @grahampugh for the inspiration)
  • Installomator now detects when an app is already installed, and will display notifications correctly the user based on if the app was updated or installed for the first time.
  • New variables for labels that should be installed using CLI: CLIInstaller and CLIArguments. When the installer app is named differently than the installed app, then the variable installerTool should be used to name the app that should be located in the DMG or zip. See the label adobecreativeclouddesktop to see its use.
  • buildLabel.sh has been improved to build GitHub software labels much easier. In essense if the URL contains github.com, then it will try to find if it’s the latest version or if variable archiveName is needed for finding the software. Also improved messaging throughout the script, as well as handling a situation where a pkg does not include a “Distribution” file, but a “PackageInfo”.
  • MDM script extended with caffeinate so Mac will not go to sleep during the time it takes installomator to run. Especially during setup, this can be useful.
  • Microsoft labels with updateTool variable, is updated to run msupdate --list before running the updateTool directly. Problems have been reported that the update would fail if the --list parameter for the command was not run first. This should help with the Jamf agent stalling during installation.
  • Added bunch of new labels (for a total of 364), and improved others

Most of the work for v8 was done by Søren Theilgaard, but we had many, many contributions from the community! Thanks to everyone!

Save up to 25% pkg file size with this weird Monterey trick!

macOS 12 Monterey brings with it a lot of new features, both for admins and users. You will probably be busy learning and experimenting with them right now, unless you already did that during the beta phase.

But, as usual, there are also many undocumented new changes and features hidden away in the update. I discovered one in the pkgbuild man page. pkgbuild, as the name implies, is used by developers and admins to build installer packages, or pkg files. Even when you are using a tool like munki-pkg or AutoPkg, it is probably using pkgbuild to assemble the installer package.

If you want to learn more about pkgbuild and creating installer packages, read my book: “Packaging for Apple Administrators“

Large Payloads and Minimum Versions

“Discovered” is a strong word here. I stumbled over this as I was looking for a different new option for pkgbuild in Monterey. In a converstation with the ever awesome Duncan McCracken, he mentioned that the tool had gained an new option, --large-payload, which allows for individual files in the payload to be larger than 8GB.

This is a significant change to the pkg file format, so pkg installers created with this option will not work on systems older than 12.0. “This option requires the user to pass --min-os-version 12.0 or later to acknowledge this requirement.” (quote from the man page)

This comment led me to look for the description of the --min-os-version option and right between --large-payload and --min-os-version I stumbled over --compression.

There is no indication that these are new options in the man page. There is also no mention of any of these new options in the Developer Release Notes or the AppleSeed for IT release notes.

Payload Compression

The description for the --compression option reads:

--compression compression-mode
Allows control over the compression used for the package. This option does not affect the compression used for plugins or scripts. Not specifying this option will leave the chosen compression algorithm up to the operating system. Two compression-mode arguments are supported:

• legacy forces a 10.5-compatible compression algorithm for the package.

• latest enables pkgbuild to automatically select newer, more efficient compression algorithms based on what is provided to [--min-os-version <version>].

With this new option, in combination with the --min-os-version option, we can influence the compression algorithm used for the payload inside the pkg file. Other than that, we are left in the dark. What kind of compression algorithms? And which minimum macOS versions use which compression algorithms?

The man page is silent on this, so we need to experiment!

Lots of pkgs

After some less organized experimentation, I put together this one-liner:

for x in 10.{5..15} 11 12; do caffeinate time pkgbuild --component /Applications/Numbers.app --min-os-version $x --compression latest Numbers-min$x.pkg; done

This is very, well, compressed, so I will explain it in steps:

Brace expansion

for x in 10.{5..15} 11 12; do

If I used for x in 10 11 12; do the shell would loop through the list using the values 10, 11, and 12. However, I also need eleven versions starting with 10. so I use the ‘brace expansion:’ 10.{5..15} will expand to 10.5, 10.6, 10.7, … until 10.15.

Brace expansion is rarely used but a very useful shell feature.

This for loop will loop through 10.5 through 10.15, and then 11 and 12, as well.

caffeinate

I did not want the MacBook I was testing on to fall asleep during the test. The caffeinate will prevent a Mac from sleeping. Most people use this command as a standalone command where it will prevent the Mac from sleeping indefinitely. Maybe you have used caffeinate -t 3600 to prevent sleep for a certain time.

But you can also use caffeinate together with a second command, and then caffeinate will prevent sleep for as long as the second command is running. For example:

caffeinate system_profiler

will prevent the Mac from falling asleep while system_profiler does its thing, which always seems like it takes ages.

The default mode of caffeinate will only prevent system sleep. The display may still dim, sleep, or even lock. If you want to prevent that as well, use caffeinate -di.

time

I was interested in the duration each pkgbuild run would take. The time command will give you that information. For example, when you run time system_profiler the system_profiler command will run, showing all its output, but the time command will add this at the end:

system_profiler  11.64s user 7.35s system 53% cpu 35.493 total

The first number (sometimes called the ‘real’ time) is the time that elapsed on the clock from the start to end of the process. The ‘user’ is also interesting as it gives the cpu time the process itself was actively running (and not waiting for other processes). Confusingly, the user time may be larger than the real time. This means the process was running on multiple cpus at once.

pkgbuild

And then we have the actual pkgbuild command using the --compression and the --min-os-version to build a pkg installer from the Numbers application on my system. I chose Numbers.app because it is fairly large (589MB) so the compression algorithm has something to do.

Results

I ran this on a MacBook Air M1 with 8GB of RAM. While pkgbuild was doing its work, I kept doing other tasks on the Mac. You can see that the run times vary by a few seconds. The system was experiencing memory pressure as the commands ran. This test wasn’t really very accurate, but the quality of the output, as you will see, is good enough to yield conclusions.

After running the above command I had 13 pkg files. and I created a chart with the output from the time command and the pkg file sizes.

When you chart the resulting filesize against the --min-os-version you see a distinct change in 10.10:

The filesizes will vary by a few bytes, but I presume that stems from different timestamps and a different minimum OS version set in the metadata of each package.

The same chart with the time required to create the pkg file:

When you use a --min-os-version value of 10.10 or higher, the file size drops by about 24% but the creation time (the ‘real’ value) nearly doubles. The ‘user’ time value increases nearly ten-fold and you may wonder how the user time can be so much higher than the ‘real’ time elapsed. The explanation is that the legacy compression algorithm uses only a single core, while the 10.10+ compression algorithm uses all available cores.

From 10.10 (Yosemite) on, the numbers stay fairly constant, all the way to 12.0, so my assumption is the compression algorithm stays the same.

Compression Algorithm

So which compression algorithms are actually used?

To figure this out, I first wanted to know if the file type of the pkg file file itself changed:

> file *.pkg    
Numbers-min10.5.pkg:   xar archive compressed TOC: 709, SHA-1 checksum, contains zlib compressed data
...
Numbers-min11.pkg:     xar archive compressed TOC: 706, SHA-1 checksum, contains zlib compressed data
Numbers-min12.pkg:     xar archive compressed TOC: 708, SHA-1 checksum, contains zlib compressed data
Numbers-minLegacy.pkg: xar archive compressed TOC: 708, SHA-1 checksum, contains zlib compressed data

As you can see the format of the wrapping archive of the pkg installer remains the same. This is probably necessary so that old versions of macOS can read the metadata inside the pkg.

But inside the pkg, is another compressed archive. You can see this when you run

> pkgutil --expand Numbers-min10.5.pkg 10.5Pkg
> ls 10.5Pkg
Bom         PackageInfo Payload
> file 10.5Pkg/Payload    
10.5Pkg/Payload: gzip compressed data, from Unix, original size modulo 2^32 594074112

Up to and including 10.9 the Payload is a gzip archive. From 10.10 upward the file command returns only data:

> file 10.10Pkg/Payload 
10.10Pkg/Payload: data

On an educated guess, I tried to list the contents of the 10.10 payload with the aa command which reads and writes the poorly documented ‘Apple Archive’ format:

> aa list -i 10.10Pkg/Payload    
.
./Numbers.app
./Numbers.app/Contents
./Numbers.app/Contents/_CodeSignature
./Numbers.app/Contents/_CodeSignature/CodeResources
...

(Note: the aa command is available on macOS Big Sur and higher.)

Expanding

When I saw how much more compute intensive the compression was, I was a bit concerned the decompression might be compute intensive on old hardware. To see if that would be a problem I used my 2012 Mac mini (the server model) running Catalina 10.15.7.

Catalina does not have the aa command line tool, (it was added in Big Sur) but pkgutil has an undocumented --expand-full option which will expand the pkg and the payload. So, I used that as a comparison:

> time pkgutil --expand-full Numbers-min10.10.pkg 10.10ExpandFull/

The M1 MacBook Air took 8.97 seconds for this operation, the 2012 Mac mini took 15.46. While that is slower, it is not a dramatic difference.

For comparison, expanding a legacy compressed file took 1.76 seconds (M1 MacBook Air) and 3.98 seconds (Mac mini 2021). The decompression is about four times slower using the new compression.

But what about productbuild?

For admins, component pkgs built with pkgbuild, are sufficient for most tasks, but sometimes developers require distribution packages. Developers generally prefer to build distribution packages.

For details on the differences of the package types and when you need which type, watch my MacDevOps YVR 2021 presentation: The Encyclopedia of Packages

The productbuild command line tool builds distribution packages. Since distribution pkgs can be far more complex than component packages, this tool has many more options. (Read my Packaging book for details.) But it has a similar mode to quickly build a distribution pkg from an app bundle:

> caffeinate time productbuild --component /Applications/Numbers.app NumbersDistDefault.pkg
productbuild: Adding component at /Applications/Numbers.app
productbuild: Inferred install-location of /Applications
productbuild: Wrote product to NumbersDistDefault.pkg
productbuild: Supported OS versions: [Min: 11.0, Before: None]
       28.85 real        22.43 user         3.42 sys

From the timing, we can guess that is creating a legacy compressed payload.

When we dig into the man page for productbuild on Monterey, we find a --component-compression option, which sounds promising. It has three options: legacy, auto, and default. The man page states that default behaves the same as legacy but that “may change in future releases of OS X.”

> caffeinate time productbuild --component /Applications/Numbers.app --component-compression auto NumbersDist.pkg
productbuild: Adding component at /Applications/Numbers.app
productbuild: Inferred install-location of /Applications
productbuild: Wrote product to NumbersDist.pkg
productbuild: Supported OS versions: [Min: 11.0, Before: None]
       44.87 real       207.40 user         8.70 sys

In this case the time suggests this uses the Apple Archive compression. But we didn’t have to provide a minimum OS version. The trick here is in the last output line of productbuild. There we see that productbuild automatically determined a minimum OS version from the application bundle. It reads the LSMinimumSystemVersion key from the app bundle’s Info.plist for this.

This is even more flexible than generically setting a min OS version of 10.10.

However, this will only work with the --component option of productbuild. Usually you have to build the components individually with pkgbuild and combine them with productbuild and in that workflow you will have to provide the minimum OS version for each component. Or determine it dynamically from the source, which is even more flexible.

Conclusion

We have learned that when you use the --compression latest with a --min-os-version of 10.10 or higher the pkg creation uses the Apple Archive compression for the payload, leading to smaller pkg file sizes. I did a few more tests with some other apps and the file compression improvements were between 20% and 25%.

When I set out to explore this, I did not expect a new compression algorithm to be present except maybe in the lastest macOS releases. This would have meant admins (who usually need to support at least two or three versions back) would have had to wait a few years before we could use a new compression algorithm, unless they were pushing the bleeding edge. However, a minimum macOS version of 10.10 means that a large majority of Apple Admins should be able to use this.

Most of the software deployed will have higher system requirements than OS X Yosemite. The minimum OS version for the package should be determined dynamically from the contents, pkgbuild and productbuild will then use the appropriate compression. The --component-compression auto option for productbuild has this dynamic behavior, but it should not be too complicated to add similar logic to your package creation workflows.

You might ask if a ~20-25% reduction in file size is really worth the extra effort of updating your packaging workflows. Since many management systems are now hosted in the cloud, every bit you can save in up- and download might have a noticeable price, if not in bandwidth costs, then in time saved for user downloading the pkg. The savings will be multiplied by the number of clients, which adds up quickly with large fleets.

I think that most effective application of this knowledge would be to have an option in your packaging workflow to use this better compression. For that, the packaging workflow will have to run on Monterey. AutoPkg is the best example of such a workflow, but there are other tools, like Packages.app or munki-pkg which could profit from this, as well.