diff --git a/Cargo.toml b/Cargo.toml
index 4e01422..08e89be 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -6,3 +6,4 @@ edition = "2021"
 [dependencies]
 bevy = { version = "0.16", features = ["dynamic_linking"] }
 bevy-inspector-egui = "0.32.0"
+rand = "0.9.2"
diff --git a/src/asteroids.rs b/src/asteroids.rs
index d389ce2..c1d09e4 100644
--- a/src/asteroids.rs
+++ b/src/asteroids.rs
@@ -1,4 +1,5 @@
 use std::time::Duration;
+use rand::SeedableRng;
 
 /// This is the module containing all the rock-related things
 /// not... not the whole game.
@@ -17,6 +18,7 @@ pub enum AsteroidSize {
 
 #[derive(Resource)]
 pub struct AsteroidSpawner {
+    rng: std::sync::Mutex<rand::rngs::StdRng>,
     timer: Timer,
     // TODO: Configurables?
     // - interval
@@ -27,6 +29,7 @@ pub struct AsteroidSpawner {
 impl AsteroidSpawner {
     pub fn new() -> Self {
         Self {
+            rng: std::sync::Mutex::new(rand::rngs::StdRng::from_seed(crate::config::RNG_SEED)),
             timer: Timer::new(Duration::from_secs(3), TimerMode::Repeating),
         }
     }
diff --git a/src/config.rs b/src/config.rs
index fd585af..9f0aa61 100644
--- a/src/config.rs
+++ b/src/config.rs
@@ -16,3 +16,5 @@ pub(crate) const ASTEROID_SMALL_COLOR: Color = Color::srgb(1.0, 0., 0.);
 
 pub(crate) const SHIP_THRUST: f32 = 1.0;
 pub(crate) const SHIP_ROTATION: f32 = 0.1; // +/- rotation speed in... radians per frame
+
+pub const RNG_SEED: [u8; 32] = *b"12345678909876543210123456789098";