diff --git a/src/controller_examples/rabbitmq_controller/exec/reconciler.rs b/src/controller_examples/rabbitmq_controller/exec/reconciler.rs
index 6d47504f2..2d7e6f987 100644
--- a/src/controller_examples/rabbitmq_controller/exec/reconciler.rs
+++ b/src/controller_examples/rabbitmq_controller/exec/reconciler.rs
@@ -39,7 +39,7 @@ impl RabbitmqReconcileState {
 pub struct RabbitmqReconciler {}
 
 #[verifier(external)]
-impl Reconciler<RabbitmqCluster, RabbitmqReconcileState, EmptyType, EmptyType, EmptyLib> for RabbitmqReconciler {
+impl Reconciler<RabbitmqCluster, RabbitmqReconcileState, EmptyType, EmptyType, EmptyAPI> for RabbitmqReconciler {
     fn reconcile_init_state(&self) -> RabbitmqReconcileState {
         reconcile_init_state()
     }
diff --git a/src/controller_examples/simple_controller/exec/reconciler.rs b/src/controller_examples/simple_controller/exec/reconciler.rs
index 816ba39a9..ae310e88c 100644
--- a/src/controller_examples/simple_controller/exec/reconciler.rs
+++ b/src/controller_examples/simple_controller/exec/reconciler.rs
@@ -33,7 +33,7 @@ impl SimpleReconcileState {
 pub struct SimpleReconciler {}
 
 #[verifier(external)]
-impl Reconciler<CustomResource, SimpleReconcileState, EmptyType, EmptyType, EmptyLib> for SimpleReconciler {
+impl Reconciler<CustomResource, SimpleReconcileState, EmptyType, EmptyType, EmptyAPI> for SimpleReconciler {
     fn reconcile_init_state(&self) -> SimpleReconcileState {
         reconcile_init_state()
     }
diff --git a/src/external_api/exec.rs b/src/external_api/exec.rs
index 6c2fa5da9..74870ed6d 100644
--- a/src/external_api/exec.rs
+++ b/src/external_api/exec.rs
@@ -1,6 +1,6 @@
 // Copyright 2022 VMware, Inc.
 // SPDX-License-Identifier: MIT
-use crate::external_api::spec::*;
+use crate::external_api::spec::EmptyTypeView;
 use crate::pervasive_ext::to_view::*;
 use vstd::{prelude::*, view::*};
 
@@ -17,10 +17,10 @@ pub trait ExternalAPI<Input: ToView, Output: ToView> {
 
 // An empty library that implements External Library.
 // This can be used by those controllers that don't rely on a third-party library.
-// Users can define a reconciler as Reconciler<xx, xx, EmptyType, EmptyType, EmptyLib>.
-pub struct EmptyLib {}
+// Users can define a reconciler as Reconciler<xx, xx, EmptyType, EmptyType, EmptyAPI>.
+pub struct EmptyAPI {}
 
-impl ExternalAPI<EmptyType, EmptyType> for EmptyLib {
+impl ExternalAPI<EmptyType, EmptyType> for EmptyAPI {
     fn transition(input: EmptyType) -> Option<EmptyType> {
         Option::None
     }
diff --git a/src/rabbitmq_controller.rs b/src/rabbitmq_controller.rs
index 2b70e1587..12dc0dfeb 100644
--- a/src/rabbitmq_controller.rs
+++ b/src/rabbitmq_controller.rs
@@ -39,7 +39,7 @@ async fn main() -> Result<()> {
         println!("{}", serde_yaml::to_string(&deps_hack::RabbitmqCluster::crd())?);
     } else if cmd == String::from("run") {
         println!("running rabbitmq-controller");
-        run_controller::<deps_hack::RabbitmqCluster, RabbitmqCluster, RabbitmqReconciler, RabbitmqReconcileState, EmptyType, EmptyType, EmptyLib>().await?;
+        run_controller::<deps_hack::RabbitmqCluster, RabbitmqCluster, RabbitmqReconciler, RabbitmqReconcileState, EmptyType, EmptyType, EmptyAPI>().await?;
         println!("controller terminated");
     } else {
         println!("wrong command; please use \"export\" or \"run\"");
diff --git a/src/simple_controller.rs b/src/simple_controller.rs
index 0a70d9652..b90cc3afb 100644
--- a/src/simple_controller.rs
+++ b/src/simple_controller.rs
@@ -39,7 +39,7 @@ async fn main() -> Result<()> {
         println!("{}", serde_yaml::to_string(&deps_hack::SimpleCR::crd())?);
     } else if cmd == String::from("run") {
         println!("running simple-controller");
-        run_controller::<deps_hack::SimpleCR, CustomResource, SimpleReconciler, SimpleReconcileState, EmptyType, EmptyType, EmptyLib>().await?;
+        run_controller::<deps_hack::SimpleCR, CustomResource, SimpleReconciler, SimpleReconcileState, EmptyType, EmptyType, EmptyAPI>().await?;
         println!("controller terminated");
     } else {
         println!("wrong command; please use \"export\" or \"run\"");