Containers is an package application with all the files, libraries, and runtime it needs. They are a common way to develop, test, and deploy server software, most known are docker containers at the moment and in macOS the two most common tools: Docker desktop and OrbStack.

Apple’s container tool takes a different approach: it creates and runs Linux containers using lightweight virtual machines on Apple silicon Macs. It works with OCI-compatible images, so you can pull images from standard registries and build images that can run in other OCI-compatible tools.

This guide walks through installing container, starting the system service, running an Ubuntu shell, and building a simple “Hello, world” web server.

What you need

• A Mac with Apple silicon: M1, M2, M3, M4, or newer
• macOS 26
• Administrator access to install the tool

Apple supports container on macOS 26 because it depends on newer virtualization and networking features. Older macOS versions may work for some workflows, but they are not officially supported. Command availability can also vary by macOS version.

Install container

Download the latest signed installer from the Apple container GitHub releases page:

https://github.com/apple/container/releases

Open the .pkg file and follow the installer prompts.

follow the below instracturions

After installation, open Terminal and start the system service:

container system start

The first time you run this command, container may ask whether you want to install a recommended Linux kernel. Type y and press Enter.

Example output:

❯ container system start

Launching container-apiserver...
Testing access to container-apiserver...
Verifying machine API server is running...
No default kernel configured.
Install the recommended default kernel from [https://github.com/kata-containers/kata-containers/releases/download/3.28.0/kata-static-3.28.0-arm64.tar.zst]? [Y/n]: y
Installing kernel...

Check that the service is running:

container system status

output:

❯ container system status

FIELD              VALUE
status             running
appRoot            /Users/A93162639/Library/Application Support/com.apple.container/
installRoot        /usr/local/
logRoot
apiserver.version  container-apiserver version 1.0.0 (build: release, commit: ee848e3)
apiserver.commit   ee848e3ebfd7c73b04dd419683be54fb450b8779
apiserver.build    release
apiserver.appName  container-apiserver

Then list all containers:

container list --all

An empty table is fine. It means the service is running and you have not created any containers yet.

Test it with an Ubuntu shell

Now run your first Linux container and attach an interactive shell:

container run -it ubuntu:latest /bin/bash

Inside the container, try:

uname -a

cat /etc/os-release

You should see Linux system information and Ubuntu release details:

root@9bb5a5b9-40a6-4a55-8093-f76c7d70c8eb:/# uname -a
Linux 9bb5a5b9-40a6-4a55-8093-f76c7d70c8eb 6.18.15 #1 SMP Tue Mar 17 01:36:53 UTC 2026 aarch64 GNU/Linux

root@9bb5a5b9-40a6-4a55-8093-f76c7d70c8eb:/# cat /etc/os-release
PRETTY_NAME="Ubuntu 26.04 LTS"
NAME="Ubuntu"
VERSION_ID="26.04"
VERSION="26.04 LTS"
ID=ubuntu
ID_LIKE=debian

Your Ubuntu version and kernel version may differ depending on when you run the command. The important part is that you are inside a Linux environment running on your Mac.

Exit the container:

exit

Limit Resources: CPU - MEM

Another useful feature is when you want to limut resources, like CPU and Memory inside the apple container. You can simple do that by:

container run -it --cpus 2 --memory 2G ubuntu:latest /bin/bash

result:

root@e3beed8c-42f0-4aaa-8fc6-e1d8d969641f:/# top -bn1 -1
top - 21:03:33 up 0 min,  0 users,  load average: 0.06, 0.02, 0.00
Tasks:   2 total,   1 running,   1 sleeping,   0 stopped,   0 zombie
%Cpu0  :  0.0 us,  0.0 sy,  0.0 ni,100.0 id,  0.0 wa,  0.0 hi,  0.0 si,  0.0 st
%Cpu1  :  0.0 us,  0.0 sy,  0.0 ni,100.0 id,  0.0 wa,  0.0 hi,  0.0 si,  0.0 s
%Cpu2  :  0.0 us,  0.0 sy,  0.0 ni,100.0 id,  0.0 wa,  0.0 hi,  0.0 si,  0.0 st
MiB Mem :   2113.3 total,   1909.6 free,     71.0 used,    154.2 buff/cache       MiB Swap:      0.0 total,      0.0 free,      0.0 used.   2042.3 avail Mem 

    PID USER      PR  NI    VIRT    RES    SHR S  %CPU  %MEM     TIME+ COMMAND
      1 root      20   0    5128   3808   3280 S   0.0   0.2   0:00.01 bash
      9 root      20   0    7060   4452   2548 R   0.0   0.2   0:00.00 top

root@e3beed8c-42f0-4aaa-8fc6-e1d8d969641f:/# grep -c ^processor /proc/cpuinfo
3

root@291ed90e-621e-460e-ae70-73f4befcb0a4:/# free
               total        used        free      shared  buff/cache   available
Mem:         2163972       68876     1959220           4      157972     2095096
Swap:              0           0           0
root@291ed90e-621e-460e-ae70-73f4befcb0a4:/#
root@291ed90e-621e-460e-ae70-73f4befcb0a4:/# 

Now list running containers:

container list

You may see an empty table because the Ubuntu shell exited. To include stopped containers, run:

container list --all

Example:

ID                                    IMAGE                            OS     ARCH   STATE    IP  CPUS  MEMORY   STARTED
9bb5a5b9-40a6-4a55-8093-f76c7d70c8eb  docker.io/library/ubuntu:latest  linux  arm64  stopped      4     1024 MB  2026-06-24T20:15:59Z

Build a “Hello, world” web server

Next, build a tiny Python web server image.

Create a new project directory:

mkdir hello-container
cd hello-container

Create a file called Dockerfile:

touch Dockerfile

Open it in your editor and paste:

FROM docker.io/python:alpine

WORKDIR /app

RUN echo '<h1>Hello from Apple container!</h1>' > index.html

CMD ["python3", "-m", "http.server", "80"]

This image starts from a lightweight Python base image, creates a simple HTML page, and runs Python’s built-in web server on port 80.

Build the image

From the same directory as your Dockerfile, run:

container build --tag hello-web --file Dockerfile .

The . at the end tells the builder to use the current directory as the build context. The command pulls the base image, runs the Dockerfile instructions, and tags the result as hello-web.

After your first build, you may see a builder container when you list containers. That is expected; container uses it to build images.

Run the web server

Start the container in the background:

container run --name my-site --detach --rm hello-web

Here’s what the flags mean:

• --name my-site gives the container a friendly name.
• --detach runs it in the background.
• --rm automatically removes the container when it stops.

List running containers:

container list

Look for the IP address in the IP column. It may look something like this:

ID        IMAGE                                                OS     ARCH   STATE    IP               CPUS  MEMORY   STARTED
my-site   hello-web:latest                                     linux  arm64  running  192.168.64.4/24  4     1024 MB  2026-06-24T20:28:15Z
buildkit  ghcr.io/apple/container-builder-shim/builder:0.12.0  linux  arm64  running  192.168.64.3/24  2     2048 MB  2026-06-24T20:27:48Z

Open the site in your browser:

open http://192.168.64.4

Replace 192.168.64.4 with the IP address shown on your machine.

You should see:

Hello from Apple container!

Optional: use localhost instead

If you prefer opening the site through localhost, publish the container port to your Mac. The container run command supports --publish / -p for mapping a container port to a host port.

Stop the current container first:

container stop my-site

Then run it again with port publishing:

container run --name my-site --detach --rm --publish 8080:80 hello-web

Open:

open http://localhost:8080

This maps port 8080 on your Mac to port 80 inside the container.

View logs

To see what the web server is logging, run:

container logs my-site

You should see HTTP request logs from Python’s web server.

result:

❯ container logs my-site
192.168.64.1 - - [24/Jun/2026 20:36:03] "GET / HTTP/1.1" 200 -
192.168.64.1 - - [24/Jun/2026 20:36:03] code 404, message File not found
192.168.64.1 - - [24/Jun/2026 20:36:03] "GET /favicon.ico HTTP/1.1" 404 -

Clean up

Stop the container:

container stop my-site

Because you started it with --rm, container removes it automatically after it stops.

Check again:

container list --all

The my-site container should no longer appear.

That’s it,
Evaggelos!

The purpose of this blog post is to act as a visual guide/tutorial on how to setup an iOS device (iPad or iPhone) using the native apps against a custom Linux Mail, Calendar & Contact server.

Disclaimer: I wrote this blog post after 36hours with an apple device. I have never had any previous encagement with an apple product. Huge culture change & learning curve. Be aware, that the below notes may not apply to your setup.

Original creation date: Friday 12 Oct 2018
Last Update: Sunday 18 Nov 2018

Linux Mail Server

Notes are based on the below setup:

• CentOS 6.10
• Dovecot IMAP server with STARTTLS (TCP Port: 143) with Encrypted Password Authentication.
• Postfix SMTP with STARTTLS (TCP Port: 587) with Encrypted Password Authentication.
• Baïkal as Calendar & Contact server.

Thunderbird

Thunderbird settings for imap / smtp over STARTTLS and encrypted authentication

Baikal

Dashboard

CardDAV

contact URI for user Username

https://baikal.baikal.example.org/html/card.php/addressbooks/Username/default

CalDAV

calendar URI for user Username

https://baikal.example.org/html/cal.php/calendars/Username/default

iOS

There is a lot of online documentation but none in one place. Random Stack Overflow articles & posts in the internet. It took me almost an entire day (and night) to figure things out. In the end, I enabled debug mode on my dovecot/postifx & apache web server. After that, throught trail and error, I managed to setup both iPhone & iPad using only native apps.

Mail

Open Password & Accounts & click on New Account

Choose Other

Now the tricky part, you have to click Next and fill the imap & smtp settings.

Now we have to go back and change the settings, to enable STARTTLS and encrypted password authentication.

STARTTLS with Encrypted Passwords for Authentication

In the home-page of the iPad/iPhone we will see the Mail-Notifications have already fetch some headers.

and finally, open the native mail app:

Contact Server

Now ready for setting up the contact account

https://baikal.baikal.example.org/html/card.php/addressbooks/Username/default

Opening Contact App:

Calendar Server

https://baikal.example.org/html/cal.php/calendars/Username/default