If you have multiple Macs, there are some ways to keep things — files, preferences, and even apps — synced across them. The more complete solutions, though, either require a complex setup or are expensive. However, there’s a way to keep your Mac devices identical (for the most part) with minimal configuration, using SyncThing and Syncalicious.
What Means Keeping Multiple Mac Devices Completely Synced, Exactly?
Think of it as using the same Mac… but across multiple Macs. Your files, preferences, and apps, all look the same no matter which computer you’re using. Installing an app, changing a setting, or downloading a file on one machine, automatically applies to all of them.
Doesn’t iCloud Drive Do That Already?
Only partially. By default, iCloud Drive has a setting to sync the Desktop and Documents folders across your Macs. However, this option lacks important features:
- Obviously, it only syncs these two folders. Whatever you place in Pictures, Movies, or Downloads, e.g., won’t be available on other devices. To sync these, you need to manually move the files and folders to iCloud Drive, and then to the other Macs.
- It consumes your iCloud Drive storage. Therefore, if you don’t subscribe to the more expensive plans, you’ll quickly run out of space.
- The sync doesn’t always work reliably. In some extreme cases, it may even leave your Desktop completely empty due to a sync error.
Keeping Macs Identical Is Possible, But Hard
Now, before we move on to the guide itself, I’ll digress really quickly. That’s because there are solutions more effective than the one I’ll teach below.
All the methods have been suggested in a Reddit post on r/macapps. The OP asked for tools to keep different devices synced, and all alternatives will work satisfactorily. However, each of them has its own shortcomings.
ChronoSync is the first alternative that comes to mind. The app’s main feature is precisely keeping two (or more) Macs identical. However, each Mac needs a separate license, which varies from $30 to almost $40 depending on how many you purchase. It’s not a terrible deal for a lifetime subscription, but still, shelling out at least $75 upfront isn’t pleasant.
The other way involves using nix-darwin, a version of the Nix package manager for macOS. In short, a package manager is like an App Store that runs in Terminal. The drawback here is that setting up Nix requires a lengthy process and previous knowledge about scripting and Terminal commands. After setting up the package manager, you’ll also need to configure Nix Home Manager (or, rather, home-manager). It’s home-manager that does the syncing, not Nix itself, so it’s a two-step procedure, and two tedious steps.
Using SyncThing and Syncalicious To Keep Multiple Mac Devices Synced
Now, for the next best thing. Using Syncalicious and SyncThing you can keep most stuff on your Macs synchronized. The latter requires an initial setup way simpler than Nix, while the former works out of the box. Both are open-source projects, and completely free as well.
One major drawback is that Syncalicious isn’t actively maintained, so it may not work reliably, especially on newer macOS versions. However, since the code is available on GitHub, anyone with the technical knowledge can try and fix issues by themselves. While at that, you can check SyncThing’s repository as well.
Installing and Setting Up Syncalicious
Syncalicious will ensure your preferences stay consistent between your devices. It automatically detects which apps are present in your Macs, and allows you to share settings amongst them.
The first thing to do is download Syncalicious from the app’s Releases page and run it on your Mac. Give the app the required permissions and point it to a folder that syncs online on all your devices.
In this case, there’s no problem using iCloud Drive: app preferences are stored in small text files. They’re called Property Lists, or PLists for short. Each .plist file weighs a few hundred kB at most, and often much less than that. Therefore, even if you have hundreds of installed apps, storing their preferences in iCloud Drive won’t make a huge difference in your available storage.
After setting Syncalicious up on all Macs, open the app’s window (tip: it starts showing only the menu bar icon). On the left, you’ll see the list of installed apps. On the right, buttons to back up and sync the preferences across devices. Below that is a list of Macs that have the app installed. Syncing the preferences is as simple as clicking Sync for each app, in each computer.
Installing and Setting Up SyncThing
First, download SyncThing from the app’s page. As the page shows, it has versions for multiple OSes, so you’re not limited to syncing files across Macs.
After installing SyncThing, the app will also live in your menu bar. Click the icon, then Open. You’ll see the settings page, with a folder list on the left and some device information on the right.
In short, the configuration process starts by selecting which folders you want to share from each device. After that, you’ll connect your devices with each other. The final step is linking one device’s folders with its counterpart in the other devices. When the initial syncing finishes, any changes made to a folder in one device will be reproduced in the others.
This is done through identifier codes for both folders and devices. The procedure isn’t as simple as described above, but it’s way less complicated than the alphanumeric codes make it seem. I have detailed the steps in my article about Möbius Sync, the iOS port of SyncThing. You can head there for detailed instructions.
For user folders, I recommend syncing on a per-folder basis (i.e. syncing Downloads, Movies, Pictures, and so on). This is safer than syncing the whole folder with your username, since it may contain device-specific system files. Syncing such files between devices may cause instabilities, or worse, prevent you from logging into your macOS user account altogether.
Keeping Applications Folder Synced on Multiple Macs Using SyncThing
Now, you may be wondering: if macOS apps are all stored in the /Applications folder, can’t this folder be synced? Technically, yes, but there are major downsides to that.
Firstly, there’s the issue of app sizes. Some apps, like games, XCode, Adobe tools, or macOS installers, may weigh several GB each. If one of the synced devices has a small internal disk, syncing the /Applications folder would take precious space.
Related to limited storage is data usage. Frequently, users want to sync their folders to have everything at hand when working on the go. However, that also means inconsistent Wi-Fi availability, and, frequently, people rather use their phones as hotspots. Imagine burning through your data and hitting bandwidth caps because your MacBook was syncing Baldur’s Gate 3 from your iMac.
Lastly, there’s the same issue as when syncing the home folder: device-specific files (or, in this case, apps). Here, the risk isn’t as immediate, since most apps won’t start by themselves. However, you may open one such app by mistake, with effects ranging from brief slowdowns to kernel panics and reboots.
At first, the idea of keeping in sync folders, files, and preferences of multiple macs, may be frightening. And it’s not because of the idea itself, but because it invokes the impression of needing to perform lots of complex configurations. Luckily, with Syncalicious and SyncThing, the procedure is very straightforward, requiring a few minutes of initial setup. After that, the apps need little to no maintenance, and should remain working indefinitely.