yle="color:#393A34"><span class="token plain">feature_1_value,feature_2_value,feature_3_value;expiry_ts</span><br></span></code></pre></div></div>
<p>This format allowed:</p>
<ul>
<li>Consistent writes and reads at the group level</li>
<li>Easy parsing of feature values using the schema lookup from ZooKeeper</li>
<li>Efficient storage with minimal DB column usage</li>
<li>Support for per-group TTLs and schema evolution</li>
</ul>
<h2 class="anchor anchorWithStickyNavbar_LWe7" id="tracking-changes-in-feature