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interface</a></li></ol></li></ol></li><li class="chapter-item expanded "><a href="../workers.html">Workers</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="../synctl_workers.html">Using synctl with Workers</a></li><li class="chapter-item expanded "><a href="../systemd-with-workers/index.html">Systemd</a></li></ol></li></ol></li><li class="chapter-item expanded "><a href="../usage/administration/index.html">Administration</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="../usage/administration/admin_api/index.html">Admin API</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="../admin_api/account_validity.html">Account Validity</a></li><li class="chapter-item expanded "><a href="../usage/administration/admin_api/background_updates.html">Background Updates</a></li><li class="chapter-item expanded "><a href="../admin_api/event_reports.html">Event Reports</a></li><li class="chapter-item expanded "><a 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- <h1 id="implementing-experimental-features-in-synapse"><a class="header" href="#implementing-experimental-features-in-synapse">Implementing experimental features in Synapse</a></h1>
- <p>It can be desirable to implement "experimental" features which are disabled by
- default and must be explicitly enabled via the Synapse configuration. This is
- applicable for features which:</p>
- <ul>
- <li>Are unstable in the Matrix spec (e.g. those defined by an MSC that has not yet been merged).</li>
- <li>Developers are not confident in their use by general Synapse administrators/users
- (e.g. a feature is incomplete, buggy, performs poorly, or needs further testing).</li>
- </ul>
- <p>Note that this only really applies to features which are expected to be desirable
- to a broad audience. The <a href="../modules/index.html">module infrastructure</a> should
- instead be investigated for non-standard features.</p>
- <p>Guarding experimental features behind configuration flags should help with some
- of the following scenarios:</p>
- <ul>
- <li>Ensure that clients do not assume that unstable features exist (failing
- gracefully if they do not).</li>
- <li>Unstable features do not become de-facto standards and can be removed
- aggressively (since only those who have opted-in will be affected).</li>
- <li>Ease finding the implementation of unstable features in Synapse (for future
- removal or stabilization).</li>
- <li>Ease testing a feature (or removal of feature) due to enabling/disabling without
- code changes. It also becomes possible to ask for wider testing, if desired.</li>
- </ul>
- <p>Experimental configuration flags should be disabled by default (requiring Synapse
- administrators to explicitly opt-in), although there are situations where it makes
- sense (from a product point-of-view) to enable features by default. This is
- expected and not an issue.</p>
- <p>It is not a requirement for experimental features to be behind a configuration flag,
- but one should be used if unsure.</p>
- <p>New experimental configuration flags should be added under the <code>experimental</code>
- configuration key (see the <code>synapse.config.experimental</code> file) and either explain
- (briefly) what is being enabled, or include the MSC number.</p>
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