diff -r 4e80fb049dca -r 2e4517b55442 src/bisection_tree/refine.rs
--- a/src/bisection_tree/refine.rs	Sun Apr 27 15:56:43 2025 -0500
+++ b/src/bisection_tree/refine.rs	Sun Apr 27 20:41:36 2025 -0500
@@ -364,10 +364,10 @@
                                 let mut container = container_arc.lock().unwrap();
                                 // Safe: we just created arg_b and have a mutable exclusive
                                 // reference to self containing it.
-                                #[cfg(feature = "nightly")]
+                                #[cfg(nightly)]
                                 unsafe { Arc::get_mut_unchecked(arc_b) }
                                     .stage_refine(domain, &mut *container);
-                                #[cfg(not(feature = "nightly"))]
+                                #[cfg(not(nightly))]
                                 Arc::get_mut(arc_b).unwrap()
                                     .stage_refine(domain, &mut *container);