diff --git a/extensions/gdpr/src/Jobs/ExportJob.php b/extensions/gdpr/src/Jobs/ExportJob.php
index 6fa7137f75..e3a10113ad 100644
--- a/extensions/gdpr/src/Jobs/ExportJob.php
+++ b/extensions/gdpr/src/Jobs/ExportJob.php
@@ -20,6 +20,12 @@
 
 class ExportJob extends GdprJob
 {
+    /**
+     * Each run writes an export file and dispatches Exporting/Exported events;
+     * retries would duplicate the file and fire listeners more than once.
+     */
+    public int $tries = 1;
+
     public function __construct(private User $user, private User $actor)
     {
     }
diff --git a/extensions/package-manager/src/Job/ComposerCommandJob.php b/extensions/package-manager/src/Job/ComposerCommandJob.php
index b195a4d633..fb6ceffdfe 100644
--- a/extensions/package-manager/src/Job/ComposerCommandJob.php
+++ b/extensions/package-manager/src/Job/ComposerCommandJob.php
@@ -25,6 +25,22 @@ class ComposerCommandJob extends AbstractJob implements ShouldBeUnique
      */
     public int $timeout = 60 * 3;
 
+    /**
+     * Composer commands are not idempotent; a retry after OOM (which bypasses
+     * the handle() try/catch) could run against a partially-modified vendor/.
+     */
+    public int $tries = 1;
+
+    /**
+     * How long (seconds) the ShouldBeUnique lock is held.
+     *
+     * Without an explicit value the default is 0, meaning the lock never
+     * expires. If the worker crashes mid-install, the lock can otherwise
+     * block future dispatches until the cache TTL runs down. 600s is
+     * longer than $timeout above so it won't expire mid-run.
+     */
+    public int $uniqueFor = 600;
+
     public function __construct(
         protected AbstractActionCommand $command,
         protected string $phpVersion
@@ -67,7 +83,14 @@ public function failed(Throwable $exception): void
     public function middleware(): array
     {
         return [
-            new WithoutOverlapping(),
+            // expireAfter matches $uniqueFor above so a crashed worker
+            // can't leave the overlap lock permanently held (default 0
+            // would mean the lock never expires). dontRelease fails a
+            // duplicate dispatch cleanly instead of tight-looping it
+            // against the held lock (default releaseAfter=0).
+            (new WithoutOverlapping())
+                ->expireAfter(600)
+                ->dontRelease(),
         ];
     }
 }
diff --git a/extensions/subscriptions/src/Job/SendReplyNotification.php b/extensions/subscriptions/src/Job/SendReplyNotification.php
index a598210d3a..35a4306552 100644
--- a/extensions/subscriptions/src/Job/SendReplyNotification.php
+++ b/extensions/subscriptions/src/Job/SendReplyNotification.php
@@ -24,6 +24,12 @@ class SendReplyNotification implements ShouldQueue
     use Queueable;
     use SerializesModels;
 
+    /** The maximum number of times the job may be attempted. */
+    public int $tries = 3;
+
+    /** Delay in seconds between retries. */
+    public array $backoff = [30, 60, 120];
+
     public function __construct(
         protected Post $post,
         protected ?int $lastPostNumber
diff --git a/framework/core/src/Notification/Job/SendNotificationsJob.php b/framework/core/src/Notification/Job/SendNotificationsJob.php
index 72a9eb3ed2..e3c1a34720 100644
--- a/framework/core/src/Notification/Job/SendNotificationsJob.php
+++ b/framework/core/src/Notification/Job/SendNotificationsJob.php
@@ -17,6 +17,12 @@
 
 class SendNotificationsJob extends AbstractJob
 {
+    /**
+     * Notification::notify() uses a raw bulk insert (not upsert), so retrying
+     * would create duplicate notification rows in recipients' feeds.
+     */
+    public int $tries = 1;
+
     public function __construct(
         private readonly BlueprintInterface&AlertableInterface $blueprint,
         /** @var User[] */
diff --git a/framework/core/src/Queue/AbstractJob.php b/framework/core/src/Queue/AbstractJob.php
index 6ec8235a8c..f16abdb465 100644
--- a/framework/core/src/Queue/AbstractJob.php
+++ b/framework/core/src/Queue/AbstractJob.php
@@ -19,4 +19,10 @@ class AbstractJob implements ShouldQueue
     use InteractsWithQueue;
     use Queueable;
     use SerializesModels;
+
+    /** The maximum number of times the job may be attempted. */
+    public int $tries = 3;
+
+    /** Delay in seconds between retries. */
+    public array $backoff = [30, 60, 120];
 }