diff --git a/include/sapien/component/component.h b/include/sapien/component/component.h
index b05a3046..60db5c4a 100644
--- a/include/sapien/component/component.h
+++ b/include/sapien/component/component.h
@@ -45,6 +45,8 @@ class Component : public std::enable_shared_from_this<Component> {
   // internal only, set parent entity
   void internalSetEntity(std::shared_ptr<Entity> const &entity) { mEntity = entity; }
 
+  uint64_t getId() const { return mId; }
+
   virtual ~Component() = default;
 
   virtual std::vector<uint64_t> getSerializationDependencies() const { return {}; }
@@ -59,6 +61,18 @@ class Component : public std::enable_shared_from_this<Component> {
   uint64_t mId{};
 };
 
+struct comp_cmp {
+  bool operator()(std::shared_ptr<Component> const &a, std::shared_ptr<Component> const &b) const {
+    if (!a) {
+      return true;
+    }
+    if (!b) {
+      return true;
+    }
+    return a->getId() < b->getId();
+  }
+};
+
 } // namespace component
 } // namespace sapien
 
diff --git a/include/sapien/component/physx/articulation.h b/include/sapien/component/physx/articulation.h
index 91b34766..c06136be 100644
--- a/include/sapien/component/physx/articulation.h
+++ b/include/sapien/component/physx/articulation.h
@@ -3,8 +3,6 @@
 #include <Eigen/Eigen>
 #include <PxPhysicsAPI.h>
 #include <memory>
-#include <unordered_map>
-#include <unordered_set>
 #include <vector>
 
 #include <cereal/cereal.hpp>
diff --git a/include/sapien/component/physx/physx_system.h b/include/sapien/component/physx/physx_system.h
index eb9e601d..a9283fa6 100644
--- a/include/sapien/component/physx/physx_system.h
+++ b/include/sapien/component/physx/physx_system.h
@@ -1,4 +1,5 @@
 #pragma once
+#include "../component.h"
 #include "../system.h"
 #include "mesh_manager.h"
 #include "sapien/scene.h"
@@ -6,12 +7,15 @@
 #include "simulation_callback.hpp"
 #include <PxPhysicsAPI.h>
 #include <memory>
-#include <unordered_set>
+#include <set>
 
 namespace sapien {
 namespace component {
 class PhysxArticulation;
 class PhysxMaterial;
+class PhysxRigidDynamicComponent;
+class PhysxRigidStaticComponent;
+class PhysxArticulationLinkComponent;
 
 struct PhysxSceneConfig {
   Vec3 gravity = {0, 0, -9.81};           // default gravity
@@ -100,10 +104,11 @@ class PhysxSystem : public System {
   physx::PxScene *mPxScene;
   float mTimestep{0.01f};
 
-  std::unordered_set<std::shared_ptr<component::PhysxRigidDynamicComponent>>
+  std::set<std::shared_ptr<component::PhysxRigidDynamicComponent>,comp_cmp>
       mRigidDynamicComponents;
-  std::unordered_set<std::shared_ptr<component::PhysxRigidStaticComponent>> mRigidStaticComponents;
-  std::unordered_set<std::shared_ptr<component::PhysxArticulationLinkComponent>>
+  std::set<std::shared_ptr<component::PhysxRigidStaticComponent>, comp_cmp>
+      mRigidStaticComponents;
+  std::set<std::shared_ptr<component::PhysxArticulationLinkComponent>, comp_cmp>
       mArticulationLinkComponents;
 
   DefaultEventCallback mSimulationCallback;
diff --git a/include/sapien/component/sapien_renderer/sapien_renderer_system.h b/include/sapien/component/sapien_renderer/sapien_renderer_system.h
index 31d4f331..57c08d85 100644
--- a/include/sapien/component/sapien_renderer/sapien_renderer_system.h
+++ b/include/sapien/component/sapien_renderer/sapien_renderer_system.h
@@ -1,12 +1,13 @@
 #pragma once
 
+#include "../component.h"
 #include "../system.h"
 #include "cubemap.h"
 #include "sapien/math/vec3.h"
 #include "sapien/serialize.h"
+#include <set>
 #include <svulkan2/core/context.h>
 #include <svulkan2/scene/scene.h>
-#include <unordered_set>
 
 namespace sapien {
 namespace component {
@@ -103,11 +104,11 @@ class SapienRendererSystem : public System {
   std::shared_ptr<SapienRenderEngine> mEngine;
   std::shared_ptr<svulkan2::scene::Scene> mScene;
 
-  std::unordered_set<std::shared_ptr<SapienRenderBodyComponent>> mRenderBodyComponents;
-  std::unordered_set<std::shared_ptr<SapienRenderCameraComponent>> mRenderCameraComponents;
-  std::unordered_set<std::shared_ptr<SapienRenderLightComponent>> mRenderLightComponents;
-  std::unordered_set<std::shared_ptr<PointCloudComponent>> mPointCloudComponents;
-  std::unordered_set<std::shared_ptr<CudaDeformableMeshComponent>> mCudaDeformableMeshComponents;
+  std::set<std::shared_ptr<SapienRenderBodyComponent>, comp_cmp> mRenderBodyComponents;
+  std::set<std::shared_ptr<SapienRenderCameraComponent>, comp_cmp> mRenderCameraComponents;
+  std::set<std::shared_ptr<SapienRenderLightComponent>, comp_cmp> mRenderLightComponents;
+  std::set<std::shared_ptr<PointCloudComponent>, comp_cmp> mPointCloudComponents;
+  std::set<std::shared_ptr<CudaDeformableMeshComponent>, comp_cmp> mCudaDeformableMeshComponents;
 
   std::shared_ptr<SapienRenderCubemap> mCubemap;
 };
diff --git a/include/sapien/component/system.h b/include/sapien/component/system.h
index 0936f599..b47e319f 100644
--- a/include/sapien/component/system.h
+++ b/include/sapien/component/system.h
@@ -6,9 +6,6 @@
 
 namespace sapien {
 namespace component {
-class PhysxRigidDynamicComponent;
-class PhysxRigidStaticComponent;
-class PhysxArticulationLinkComponent;
 
 /** System controls entity components in a scene.
  *  Components should register themselves to a system to enable lifecycle methods */