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<p>The upcoming Android O release includes Project Treble, a major re-architect
of the Android OS framework designed to make it easier, faster, and less costly
for manufacturers to update devices to a new version of Android.</p>

<h2 id=about-treble>Android updates</h2>
<p>Project Treble separates the vendor implementation (device-specific,
lower-level software written by silicon manufacturers) from the Android OS
framework via a new vendor interface.</p>

<p>In Android 7.x and earlier, no formal vendor interface exists so device
makers must update large portions of the Android code to move a device to a
newer version of Android:</p>

<img src="images/treble_blog_before.png">

<p class="img-caption"><strong>Figure 1.</strong> Pre-Treble Android update
environment</p>

<p>With Treble, a new stable vendor interface provides access to the
hardware-specific parts of Android, enabling device makers to deliver new
Android releases simply by updating the Android OS framework&mdash;without any
additional work required from the silicon manufacturers:</p>

<img src="images/treble_blog_after.png">

<p class="img-caption"><strong>Figure 2.</strong> Treble Android update
environment</p>

<h2 id=testing-treble>Testing Treble</h2>
<p>To ensure forward compatibility of the vendor implementation, the new vendor
interface will be validated by the Vendor Test Suite (VTS), which is analogous
to the <a href="/compatibility/cts/">Compatibility Test Suite (CTS)</a>. VTS is
already launched and can be used to automate HAL and OS kernel testing even in
pre-Treble environments; for details, see
<a href="/devices/tech/test_infra/tradefed/fundamentals/vts">Systems Testing
With VTS</a>.</p>

<h2 id=launching-treble>Coming soon</h2>
<p>Project Treble is coming to all new devices launching with Android O and
beyond, and the new architecture is already running on the Developer Preview of
O for Pixel phones. When Android O launches, we'll have full details here (on
<a href="https://source.android.com/">source.android.com</a>). In the interim,
you can find more details on Treble over at the
<a href="https://android-developers.googleblog.com/2017/05/here-comes-treble-modular-base-for.html">Android
Developers Blog</a>.</p>


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