>>> [!note] Migrated issue <!-- Drupal.org comment --> <!-- Migrated from issue #3214464. --> Reported by: [benjifisher](https://www.drupal.org/user/683300) Related to !2 >>> <h3 id="summary-problem-motivation">Problem/Motivation</h3> <p>One of the changes in <span class="drupalorg-gitlab-issue-link drupalorg-gitlab-link-wrapper"><a href="https://git.drupalcode.org/project/migrate_scanner/-/work_items/3214186" class="drupalorg-gitlab-link">https://git.drupalcode.org/project/migrate_scanner/-/work_items/3214186</a></span> is</p> <pre>--- a/src/Plugin/MigrationPluginManager.php<br>+++ b/src/Plugin/MigrationPluginManager.php<br>@@ -23,7 +23,7 @@ class MigrationPluginManager extends DefaultMigrationPluginManager {<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; }, $this-&gt;moduleHandler-&gt;getModuleDirectories());<br> <br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; // Retrieves **/*.yml files but gets rid of /migrations/state/*.yml files.<br>-&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; $yaml_discovery = new YamlRecursiveDirectoryDiscovery($directories, 'migrate', 'id', '#/migrations/state/#');<br>+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; $yaml_discovery = new YamlRecursiveDirectoryDiscovery($directories, 'migrate', 'id', '#/migrations/(process|state)/#');</pre><p>That does not scale well. I think we need an easy way for a developer to set exclude rules while working on a custom migration.</p> <p>It might be useful to allow include rules as well as exclude rules. For example, a developer working on several related sites might want a single module (perhaps including some custom plugins) and migrations in <code>migrations/site1/</code>, <code>migrations/site2/</code>, ...</p> <h3 id="summary-proposed-resolution">Proposed resolution</h3> <p>Either add an alter hook or trigger an event so that other modules can modify the paths to be scanned.</p> <p>I think we should optimize for simplicity, not flexibility. Instead of giving other modules the list of directories and letting them manipulate it, just let them add include/exclude patterns.</p> <h3 id="summary-remaining-tasks">Remaining tasks</h3> <h3 id="summary-ui-changes">User interface changes</h3> <h3 id="summary-api-changes">API changes</h3> <p>This feature will add to the public API of this module.</p> <h3 id="summary-data-model-changes">Data model changes</h3>