diff --git a/src/birdoids/mod.rs b/src/birdoids/mod.rs
index 158aff5c..a48bda96 100644
--- a/src/birdoids/mod.rs
+++ b/src/birdoids/mod.rs
@@ -1,8 +1,12 @@
+pub mod physics;
+
 use bevy::prelude::*;
 use bevy_spatial::{
     kdtree::KDTree2, AutomaticUpdate, SpatialAccess, SpatialStructure, TransformMode,
 };
 
+use crate::birdoids::physics::{apply_velocity, Force, Velocity};
+
 const BACKGROUND_COLOR: Color = Color::srgb(0.4, 0.4, 0.4);
 const PLAYERBOID_COLOR: Color = Color::srgb(1.0, 0.0, 0.0);
 const TURN_FACTOR: f32 = 1.0;
@@ -47,14 +51,8 @@ pub(crate) struct Boid;
 #[derive(Component)]
 struct PlayerBoid;
 
-#[derive(Component, Deref, DerefMut)]
-pub(crate) struct Velocity(Vec3);
-
-#[derive(Component, Default, Deref, DerefMut, PartialEq, Debug)]
-pub(crate) struct Force(Vec3);
-
 #[derive(Component)]
-pub(crate) struct TrackedByKdTree;
+pub struct TrackedByKdTree;
 
 #[derive(Bundle)]
 struct BoidBundle {
@@ -136,15 +134,6 @@ fn turn_if_edge(
     }
 }
 
-fn apply_velocity(mut query: Query<(&mut Transform, &Velocity, &mut Force)>, time: Res<Time>) {
-    for (mut transform, velocity, mut acceleration) in &mut query {
-        let delta_v = **acceleration * time.delta_secs();
-        **acceleration = Vec3::ZERO;
-        let delta_position = (**velocity + delta_v) * time.delta_secs();
-        transform.translation += delta_position;
-    }
-}
-
 fn check_keyboard(
     keyboard_input: Res<ButtonInput<KeyCode>>,
     mut app_exit_events: ResMut<Events<bevy::app::AppExit>>,
@@ -324,7 +313,7 @@ mod tests {
 
     use crate::birdoids::{cohesive_force, separation_force};
 
-    use super::{Force, BOID_VIEW_RANGE};
+    use super::{physics::Force, BOID_VIEW_RANGE};
 
     // forces are relative to the boid's view range, so all
     // distances need to be fractions of that
diff --git a/src/birdoids/physics.rs b/src/birdoids/physics.rs
new file mode 100644
index 00000000..20b3e875
--- /dev/null
+++ b/src/birdoids/physics.rs
@@ -0,0 +1,16 @@
+use bevy::prelude::*;
+
+#[derive(Component, Deref, DerefMut)]
+pub struct Velocity(pub Vec3);
+
+#[derive(Component, Default, Deref, DerefMut, PartialEq, Debug)]
+pub struct Force(pub Vec3);
+
+pub fn apply_velocity(mut query: Query<(&mut Transform, &Velocity, &mut Force)>, time: Res<Time>) {
+    for (mut transform, velocity, mut acceleration) in &mut query {
+        let delta_v = **acceleration * time.delta_secs();
+        **acceleration = Vec3::ZERO;
+        let delta_position = (**velocity + delta_v) * time.delta_secs();
+        transform.translation += delta_position;
+    }
+}
diff --git a/src/debug_plugin.rs b/src/debug_plugin.rs
index 76127f6a..b7343aba 100644
--- a/src/debug_plugin.rs
+++ b/src/debug_plugin.rs
@@ -2,7 +2,7 @@ use bevy::{prelude::*, window::PrimaryWindow};
 use bevy_spatial::{kdtree::KDTree2, SpatialAccess};
 
 use crate::birdoids::{
-    center_of_boids, velocity_of_boids, Boid, Force, TrackedByKdTree, Velocity,
+    center_of_boids, physics::Force, physics::Velocity, velocity_of_boids, Boid, TrackedByKdTree,
 };
 
 const SCANRADIUS: f32 = 50.0;