Source code, Building, and Installation

The initial application of Synit is to mobile phones.

As such, in addition to regular system layer concepts, Synit supports concepts from mobile telephony: calls, SMSes, mobile data, headsets, speakerphone, hotspots, battery levels and charging status, and so on.

Synit builds upon many existing technologies, but primarily relies on the following:

  • PostmarketOS. Synit builds on PostmarketOS, replacing only a few core packages. All of PostmarketOS and Alpine Linux are available underneath Synit.

  • Preserves. The Preserves data language and its associated schema and query languages are central to Synit.

  • Syndicate. Syndicate is an umbrella project for tools and specifications related to the Syndicated Actor Model (the SAM).

You will need

  • A Linux development system. (I use Debian testing/unstable.)

  • Rust nightly and Cargo (perhaps installed via rustup).

  • The rust cross tool (even for x86_64 builds):

    cargo install cross
  • Docker (containers are used frequently for building packages, among other things!)

  • Python 3.9 or greater

  • git, ssh, rsync

  • Make, a C compiler, and so on; standard Unix programming tools.

  • The preserves-tool binary installed on your PATH:

    cargo install preserves-tools
  • qemu and its binfmt support (even for x86_64 builds). On Debian, apt install binfmt-support qemu-user-static.1

  • Source code for Synit components (see below).

  • A standard PostmarketOS distribution for the target computer or mobile phone. If you don't want to install on actual hardware, you can use a virtual machine. See the instructions for installing PostmarketOS.

  • Great tolerance for the possibility of soft-bricking your phone. This is experimental software! When it breaks, you'll often have to (at least) reinstall PostmarketOS from absolute scratch on the machine. I do lots of development using qemu-amd64 for this reason. See here for instructions on running Synit on a emulated device.

Here's a small shell snippet to quickly check for the dependencies you will need:2

    rustc +nightly --version
    cross +nightly --version
    docker --version
    python3 --version
    git --version
    ssh -V 2>&1
    rsync --version | head -1
    make --version | head -1
    cc --version | head -1
    preserves-tool --version
    qemu-system-aarch64 --version | head -1
    ls -la /proc/sys/fs/binfmt_misc/qemu-aarch64 2>&1
) 2>/dev/null

On my machine, it outputs:

rustc 1.78.0-nightly (878c8a2a6 2024-02-29)
cross 0.2.5
cargo 1.78.0-nightly (8964c8ccf 2024-02-27)
Docker version 20.10.25+dfsg1, build b82b9f3
Python 3.11.8
git version 2.43.0
OpenSSH_9.6p1 Debian-4, OpenSSL 3.1.5 30 Jan 2024
rsync  version 3.2.7  protocol version 31
GNU Make 4.3
cc (Debian 13.2.0-13) 13.2.0
preserves-tool 4.994.0
QEMU emulator version 8.2.1 (Debian 1:8.2.1+ds-2)
-rw-r--r-- 1 root root 0 Mar  1 15:37 /proc/sys/fs/binfmt_misc/qemu-aarch64

Get the code

The Synit codebase itself is contained in the synit git repository:

git clone

See the README for an overview of the contents of the repository.

Synit depends on published packages for Preserves and Syndicate support in each of the many programming languages it uses. These will be automatically found and downloaded during the Synit build process, but you can find details on the Preserves and Syndicate homepages, respectively.

For the Smalltalk-based phone-management and UI part of the system, you will need a number of other tools. See the README for the squeak-phone repository:

git clone

Build the packages

To build, type make ARCH=<architecture> in the packaging directory of your checkout, where <architecture> is one of:

  • aarch64 (default), for e.g. Pinephone or Samsung Galaxy S7 deployment
  • x86_64, for e.g. qemu-amd64 deployment

If you see errors of the form "exec /bin/sh: exec format error" while building, say, the aarch64 packages using an x86_64 build host, you need to install qemu's binfmt support. See above.

The result of the build will be a collection of Alpine Linux apk packages in packaging/target/packages/<architecture>/. At the time of writing, these include

  • preserves-schemas, common schema files for working with general Preserves data and schemas
  • preserves-tools, standard command-line tools for working with Preserves documents (pretty-printer, document query processor, etc.)
  • py3-preserves, python support libraries for Preserves
  • py3-syndicate, python support for the Syndicated Actor Model
  • squeak-cog-vm and squeak-stack-vm, Squeak Smalltalk virtual machine for the Smalltalk-based portions of the system
  • syndicate-schemas, common schema files for working with the Syndicated Actor Model
  • syndicate-server, package for the core system bus
  • synit-config, main package for Synit, with configuration files, init scripts, system daemons and so on.
  • synit-pid1, PID1 program for Synit that starts the core system bus and then becomes passive

Install PostmarketOS on your system

Follow the instructions for your device on the PostmarketOS wiki.

Boot and connect your device to your development machine. Make sure you can ssh into it.

Upload Synit packages

Change to the scripts/ directory, and run the ./ script from there to rsync the ingredients for transforming stock PostmarketOS to Synit to the phone.

Run the transformation script

Use ssh to log into your phone. Run ./ (If your user's password on the phone is anything other than user, you will have to run SUDOPASS=yourpassword ./

This will install the Synit packages. After this step is complete, next time you boot the system, it will boot into Synit. It may very well be unbootable at this point, depending on the state of the codebase! Make sure you know how to restore to a stock PostmarketOS installation.

Install the Smalltalk parts of the system (optional)

If you want to experiment with the Smalltalk-based modem support and UI, follow the instructions in the squeak-phone README now.

Reboot and hope

With luck, you'll see the Smalltalk user interface start up. (If you didn't install the UI, you should still be able to ssh into the system.) From here, you can operate the system normally, following the information in the following chapter.



Version 1:7.0+dfsg-7 of qemu-user-static has a bug (possibly this one) which makes Docker-based cross builds hang. Downgrading qemu-user-static to version 1:5.2+dfsg-11+deb11u2 worked for me, as did upgrading (as of October 2022) to version 1:7.1+dfsg-2.


Please contact me at if a dependency needs to be added to the list.