diff --git a/crates/engine/src/cmd/delete.rs b/crates/engine/src/cmd/delete.rs
index 05b1cfd809..d330dd79bd 100644
--- a/crates/engine/src/cmd/delete.rs
+++ b/crates/engine/src/cmd/delete.rs
@@ -336,6 +336,36 @@ mod tests {
         assert!(s.model.state().sketch(sk).unwrap().sketch.constraints.iter().all(|c| c.id != angle));
     }
 
+    /// #9917: the check before a delete in a sketch with a rolled-back history after it builds the
+    /// history before the delete only when a feature fails after it. Deleting a hole in the plate
+    /// changes the plate and every cut after it and breaks none of them: the check reports
+    /// nothing. Deleting a side of the plate's outline breaks the plate, and the check still says
+    /// so, with the cache too small to keep a state (as on a large design).
+    #[test]
+    fn a_delete_in_a_rolled_back_history_reports_what_breaks_after_the_marker_and_nothing_else() {
+        let mut s = Session::default();
+        let sk = run(&mut s, "sketch.create", json!({"plane": "XY"}))["sketch"].as_u64().unwrap();
+        let outline = run(&mut s, "sketch.line", json!({"points": [[0, 0], [40, 0], [30, 20], [10, 20]], "closed": true}))["curves"][0]
+            .as_str()
+            .unwrap()
+            .to_string();
+        let hole = run(&mut s, "sketch.circle.center", json!({"center": [30, 15], "radius": 2}))["curves"][0].as_str().unwrap().to_string();
+        run(&mut s, "sketch.finish", json!({}));
+        run(&mut s, "solid.extrude", json!({"distance": 5, "name": "Plate"}));
+        for i in 0..6 {
+            run(&mut s, "solid.cylinder", json!({"base": [12 + 3 * i, 8, -1], "radius": 1, "height": 10, "operation": "cut"}));
+        }
+        run(&mut s, "timeline.roll_to", json!({"position": 1}));
+        run(&mut s, "sketch.edit", json!({"sketch": sk}));
+        *s.model.cache.lock().unwrap() = solidcraft_doc::EvalCache::with_budget(1);
+        let doc = s.doc.clone();
+        let dry = run(&mut s, "selection.delete", json!({"items": [{"type": "sketch_curve", "id": hole}], "dry_run": true}));
+        assert_eq!(dry["would_fail"], json!([]), "{dry}");
+        let dry = run(&mut s, "selection.delete", json!({"items": [{"type": "sketch_curve", "id": outline}], "dry_run": true}));
+        assert!(dry["would_fail"].as_array().unwrap().contains(&json!("Plate")), "{dry}");
+        assert_eq!(*s.doc, *doc, "the checks change nothing");
+    }
+
     #[test]
     fn mixed_selection_is_one_undo_step() {
         let (mut s, _) = part();
diff --git a/crates/engine/src/cmd/edit.rs b/crates/engine/src/cmd/edit.rs
index 886d40b3a5..c998019df0 100644
--- a/crates/engine/src/cmd/edit.rs
+++ b/crates/engine/src/cmd/edit.rs
@@ -1353,7 +1353,14 @@ pub(super) fn newly_broken_in_history(
         model.evaluate(&doc);
         model
     };
-    newly_broken(&whole(before_doc, before), &whole(after_doc, after))
+    // Only a feature that fails after the change can be newly broken: when none does, the
+    // history before it needn't be built again (#9917: each build ran every boolean after the
+    // marker, half a minute on a large design).
+    let after = whole(after_doc, after);
+    if after.results.iter().all(|r| r.error.is_none()) {
+        return Vec::new();
+    }
+    newly_broken(&whole(before_doc, before), &after)
 }
 
 /// Whether `after_doc` differs from `before_doc` only in sketch constraints and dimensions (and