diff --git a/src/autorouter/autoroute.rs b/src/autorouter/autoroute.rs
index 90a906a..94a2af0 100644
--- a/src/autorouter/autoroute.rs
+++ b/src/autorouter/autoroute.rs
@@ -10,13 +10,13 @@ use std::ops::ControlFlow;
 use crate::{
     board::AccessMesadata,
     drawing::{band::BandTermsegIndex, graph::PrimitiveIndex, Collect},
-    geometry::primitive::PrimitiveShape,
+    geometry::{edit::ApplyGeometryEdit, primitive::PrimitiveShape},
     graph::MakeRef,
     layout::LayoutEdit,
     router::{
         navcord::Navcord, navmesh::Navmesh, thetastar::ThetastarStepper, RouteStepper, Router,
     },
-    stepper::{EstimateProgress, Step},
+    stepper::{Abort, EstimateProgress, Step},
 };
 
 use super::{
@@ -165,6 +165,15 @@ impl<M: AccessMesadata> Step<Autorouter<M>, Option<LayoutEdit>, AutorouteContinu
     }
 }
 
+impl<M: AccessMesadata> Abort<Autorouter<M>> for AutorouteExecutionStepper {
+    fn abort(&mut self, autorouter: &mut Autorouter<M>) {
+        if let Some(ref route) = self.route {
+            autorouter.board.apply(&route.navcord().recorder.reverse());
+            self.curr_ratline_index = self.ratlines.len();
+        }
+    }
+}
+
 impl EstimateProgress for AutorouteExecutionStepper {
     type Value = f64;
 
diff --git a/src/autorouter/execution.rs b/src/autorouter/execution.rs
index 61ae470..fa4a3dd 100644
--- a/src/autorouter/execution.rs
+++ b/src/autorouter/execution.rs
@@ -158,10 +158,11 @@ impl<M: AccessMesadata + Clone> Abort<Invoker<M>> for ExecutionStepper<M> {
                 // TODO: maintain topo-navmesh just like layout
                 *invoker.autorouter.board.layout_mut() = autoroute.last_layout.clone();
             }
-            execution => {
-                // TODO
-                execution.finish(invoker);
-            }
+            ExecutionStepper::Autoroute(autoroute) => autoroute.abort(&mut invoker.autorouter),
+            ExecutionStepper::PlaceVia(_place_via) => (), //place_via.abort(),
+            ExecutionStepper::RemoveBands(_remove_bands) => (), //remove_bands.abort(),
+            ExecutionStepper::CompareDetours(_compare_detours) => (), //compare_detours.abort(),
+            ExecutionStepper::MeasureLength(_measure_length) => (), //measure_length.abort(),
         }
     }
 }
diff --git a/src/stepper.rs b/src/stepper.rs
index ac4b44c..6f9dba7 100644
--- a/src/stepper.rs
+++ b/src/stepper.rs
@@ -39,21 +39,21 @@ pub trait Step<Ctx, B, C = ()> {
 }
 
 /// Steppers that may be stepped backwards implement this trait.
-pub trait StepBack<C, S, E> {
+pub trait StepBack<Ctx, S, E> {
     /// Retreat the stepper's state by one step.
-    fn step_back(&mut self, context: &mut C) -> Result<S, E>;
+    fn step_back(&mut self, context: &mut Ctx) -> Result<S, E>;
 }
 
 /// Steppers that may be aborted implement this trait.
 ///
-/// Aborting a stepper puts it in a state where stepping or stepping back always
-/// fails.
-pub trait Abort<C> {
+/// Aborting a stepper puts it and its context back in its initial state, except
+/// that from then on trying to step or step back always fails.
+pub trait Abort<Ctx> {
     /// Abort the stepper.
-    fn abort(&mut self, context: &mut C);
+    fn abort(&mut self, context: &mut Ctx);
 }
 
-/// Steppers that can receive discrete events and act on them, implement this
+/// Steppers that can receive discrete events and act on them implement this
 /// trait.
 // XXX: Doesn't this violate the rule that stepper's future states are
 // determined by its initial state?