Lacros Makes Chrome OS & Browser Better By Tearing Them Apart


Google has a project in the works codenamed "lacros" that will decouple Chrome as an OS from the Chrome browser. That's based on a recent report from Android Police citing source code documentation.

As described by the documentation, the change will separate the two parts into their own binaries. Those would be dubbed ash-chrome, for the system UI, and lacros-chrome, for the web browser. The company hopes to accomplish that by making relatively few changes to the underlying OS. But also to improve the browser's Wayland support and "make it act like the web browser on Chrome OS"

The browser would then ship as the lacros-chrome binary.


What's in a name for lacros on Chrome OS?

The lacros name was chosen as an acronym of 'Linux And ChRome OS'. Unsurprisingly, Google indicates it can be thought of as a Linux app in Chrome OS. And, as noted above, it will allow Chrome OS and Chrome to ship separately.

Now, Google isn't giving any clear answers when it comes to the reasons for its decision to separate the two on Chromebooks. But the underlying goal is provided. Namely, it wants to allow the two to be released and updated separately. And the end result of that could be wildly different version numbers for either.

For example, the initial API boundary will be semi-stable, the company says. So it will only support one or two milestones, in terms of the version difference between the two. In the search giant's example, across might launch at milestone 101. But the branch for Chrome OS itself, ash chrome, could run at milestone version 100.


Over time, that gap could widen, though, eventually allowing more degrees of separation between the two. In particular, allowing updates to one without updates to the other.

Is there a reason for this separation?

The separation itself will come with caveats, however. Most notably, those will be to performance and resource management — according to Google. Speculatively, the trade-off could be made to ensure a longer life for Chromebooks. Or at least for the Chrome browser on Chromebooks.

Typically a modern Chrome OS gadget has a shelf life of up to 6.5-years from the moment it becomes official. Although it seems unlikely the benefits of separation would be significant since Chrome OS itself would remain un-updated. So there are likely some other reasons Google is still keeping well under wraps for the time being.