diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..93526df
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,2 @@
+venv/
+__pycache__/
diff --git a/README.md b/README.md
index 14fa2f2..bacdd5e 100644
--- a/README.md
+++ b/README.md
@@ -1 +1,40 @@
-# asteroids
+# Asteroids
+
+`Asteroids` is a very simple asteroids game developed with Python and [Pygame](https://www.pygame.org/docs/).
+
+## Repository mirrors
+
+- **Code Flow:** https://codeflow.dananglin.me.uk/apollo/asteroids
+- **GitHub:** https://github.com/dananglin/asteroids
+
+## Requirements
+
+To run the application you'll need a recent version of Python 3.
+This application was built and tested with Python 3.12.3.
+
+You'll also need to install pygame.
+The installation instructions are below.
+
+## How to run the game
+
+- Clone this repository to your local machine.
+   ```
+   git clone https://github.com/dananglin/asteroids.git
+   cd asteroids
+   ```
+
+- (Optional) create a virtual environment and activate it.
+   ```
+   python3 -m venv venv
+   source venv/bin/activate
+   ```
+
+- Install the dependencies listed in `requirements.txt`.
+   ```
+   pip3 install -r requirements.txt
+   ```
+
+- Launch the game.
+   ```
+   python3 main.py
+   ```
diff --git a/asteroid.py b/asteroid.py
new file mode 100644
index 0000000..ca67bed
--- /dev/null
+++ b/asteroid.py
@@ -0,0 +1,33 @@
+import random
+import pygame
+from circleshape import CircleShape
+from constants import ASTEROID_MIN_RADIUS
+
+
+class Asteroid(CircleShape):
+    def __init__(self, x, y, radius) -> None:
+        super().__init__(x, y, radius)
+
+    def draw(self, screen) -> None:
+        pygame.draw.circle(screen, "white", self.position, self.radius, 2)
+
+    def update(self, dt: int):
+        self.position += self.velocity * dt
+
+    def split(self):
+        self.kill()
+
+        if self.radius <= ASTEROID_MIN_RADIUS:
+            return
+
+        new_radius = self.radius - ASTEROID_MIN_RADIUS
+
+        random_angle = random.uniform(20, 50)
+        vec_0 = self.velocity.rotate(random_angle)
+        vec_1 = self.velocity.rotate(-random_angle)
+
+        new_asteroid_0 = Asteroid(self.position.x, self.position.y, new_radius)
+        new_asteroid_0.velocity = vec_0 * 1.2
+
+        new_asteroid_1 = Asteroid(self.position.x, self.position.y, new_radius)
+        new_asteroid_1.velocity = vec_1 * 1.2
diff --git a/asteroidfield.py b/asteroidfield.py
new file mode 100644
index 0000000..da82d41
--- /dev/null
+++ b/asteroidfield.py
@@ -0,0 +1,51 @@
+import pygame
+import random
+from asteroid import Asteroid
+from constants import *
+
+
+class AsteroidField(pygame.sprite.Sprite):
+    edges = [
+        [
+            pygame.Vector2(1, 0),
+            lambda y: pygame.Vector2(-ASTEROID_MAX_RADIUS, y * SCREEN_HEIGHT),
+        ],
+        [
+            pygame.Vector2(-1, 0),
+            lambda y: pygame.Vector2(
+                SCREEN_WIDTH + ASTEROID_MAX_RADIUS, y * SCREEN_HEIGHT
+            ),
+        ],
+        [
+            pygame.Vector2(0, 1),
+            lambda x: pygame.Vector2(x * SCREEN_WIDTH, -ASTEROID_MAX_RADIUS),
+        ],
+        [
+            pygame.Vector2(0, -1),
+            lambda x: pygame.Vector2(
+                x * SCREEN_WIDTH, SCREEN_HEIGHT + ASTEROID_MAX_RADIUS
+            ),
+        ],
+    ]
+
+    def __init__(self):
+        pygame.sprite.Sprite.__init__(self, self.containers)
+        self.spawn_timer = 0.0
+
+    def spawn(self, radius, position, velocity):
+        asteroid = Asteroid(position.x, position.y, radius)
+        asteroid.velocity = velocity
+
+    def update(self, dt):
+        self.spawn_timer += dt
+        if self.spawn_timer > ASTEROID_SPAWN_RATE:
+            self.spawn_timer = 0
+
+            # spawn a new asteroid at a random edge
+            edge = random.choice(self.edges)
+            speed = random.randint(40, 100)
+            velocity = edge[0] * speed
+            velocity = velocity.rotate(random.randint(-30, 30))
+            position = edge[1](random.uniform(0, 1))
+            kind = random.randint(1, ASTEROID_KINDS)
+            self.spawn(ASTEROID_MIN_RADIUS * kind, position, velocity)
diff --git a/circleshape.py b/circleshape.py
new file mode 100644
index 0000000..200e532
--- /dev/null
+++ b/circleshape.py
@@ -0,0 +1,32 @@
+import pygame
+
+
+# Base class for game objects
+class CircleShape(pygame.sprite.Sprite):
+    def __init__(self, x: int, y: int, radius: int) -> None:
+        # we will be using this later
+        if hasattr(self, "containers"):
+            super().__init__(self.containers)
+        else:
+            super().__init__()
+
+        self.position = pygame.Vector2(x, y)
+        self.velocity = pygame.Vector2(0, 0)
+        self.radius = radius
+
+    def draw(self, screen):
+        # sub-classes must override
+        pass
+
+    def update(self, dt):
+        # sub-classes must override
+        pass
+
+    def is_colliding_with(self, obj: "CircleShape") -> bool:
+        distance = self.position.distance_to(obj.position)
+        radius_total = self.radius + obj.radius
+
+        if distance <= radius_total:
+            return True
+
+        return False
diff --git a/constants.py b/constants.py
new file mode 100644
index 0000000..2af71c6
--- /dev/null
+++ b/constants.py
@@ -0,0 +1,15 @@
+SCREEN_WIDTH = 1280
+SCREEN_HEIGHT = 720
+
+ASTEROID_MIN_RADIUS = 20
+ASTEROID_KINDS = 3
+ASTEROID_SPAWN_RATE = 0.8  # seconds
+ASTEROID_MAX_RADIUS = ASTEROID_MIN_RADIUS * ASTEROID_KINDS
+
+PLAYER_RADIUS = 20
+PLAYER_TURN_SPEED = 300
+PLAYER_SPEED = 200
+PLAYER_SHOOT_SPEED = 500
+PLAYER_SHOOT_COOLDOWN = 0.3
+
+SHOT_RADUIS = 3
diff --git a/main.py b/main.py
new file mode 100644
index 0000000..e04e820
--- /dev/null
+++ b/main.py
@@ -0,0 +1,64 @@
+import sys
+import pygame
+from constants import SCREEN_WIDTH, SCREEN_HEIGHT
+from player import Player
+from asteroid import Asteroid
+from asteroidfield import AsteroidField
+from shot import Shot
+
+
+def main():
+    print("Starting asteroids!")
+    print(f"Screen width: {SCREEN_WIDTH}")
+    print(f"Screen height: {SCREEN_HEIGHT}")
+
+    pygame.init()
+
+    screen = pygame.display.set_mode((SCREEN_WIDTH, SCREEN_HEIGHT))
+
+    clock = pygame.time.Clock()
+    dt = 0
+
+    updatable = pygame.sprite.Group()
+    drawable = pygame.sprite.Group()
+    asteroids = pygame.sprite.Group()
+    shots = pygame.sprite.Group()
+
+    Player.containers = (updatable, drawable)
+    Asteroid.containers = (asteroids, updatable, drawable)
+    AsteroidField.containers = updatable
+    Shot.containers = (shots, updatable, drawable)
+
+    playerObj = Player(SCREEN_WIDTH/2, SCREEN_HEIGHT/2)
+    asteroidFieldObj = AsteroidField()
+
+    # this is the game loop
+    while True:
+        for event in pygame.event.get():
+            if event.type == pygame.QUIT:
+                return
+
+        for obj in updatable:
+            obj.update(dt)
+
+        for asteroid in asteroids:
+            if playerObj.is_colliding_with(asteroid):
+                print("Game over!")
+                sys.exit(0)
+
+            for shot in shots:
+                if shot.is_colliding_with(asteroid):
+                    asteroid.split()
+                    shot.kill()
+
+        screen.fill("black")
+
+        for obj in drawable:
+            obj.draw(screen)
+
+        pygame.display.flip()
+        dt = clock.tick(60) / 1000
+
+
+if __name__ == "__main__":
+    main()
diff --git a/player.py b/player.py
new file mode 100644
index 0000000..685f5b5
--- /dev/null
+++ b/player.py
@@ -0,0 +1,58 @@
+import pygame
+from circleshape import CircleShape
+from constants import *
+from shot import Shot
+
+
+class Player(CircleShape):
+    def __init__(self, x: int, y: int) -> None:
+        super().__init__(x, y, PLAYER_RADIUS)
+
+        self.rotation = 0
+        self.timer = 0
+
+    def triangle(self):
+        forward = pygame.Vector2(0, 1).rotate(self.rotation)
+        right = pygame.Vector2(0, 1).rotate(
+            self.rotation + 90) * self.radius / 1.5
+        a = self.position + forward * self.radius
+        b = self.position - forward * self.radius - right
+        c = self.position - forward * self.radius + right
+        return [a, b, c]
+
+    def draw(self, screen) -> None:
+        pygame.draw.polygon(screen, "white", self.triangle(), 2)
+
+    def rotate(self, dt: int):
+        self.rotation += PLAYER_TURN_SPEED * dt
+
+    def update(self, dt: int):
+        keys = pygame.key.get_pressed()
+
+        if keys[pygame.K_a]:
+            self.rotate(-dt)
+
+        if keys[pygame.K_d]:
+            self.rotate(dt)
+
+        if keys[pygame.K_w]:
+            self.move(dt)
+
+        if keys[pygame.K_s]:
+            self.move(-dt)
+
+        if keys[pygame.K_SPACE]:
+            if self.timer <= 0:
+                self.shoot()
+
+        self.timer -= dt
+
+    def move(self, dt: int):
+        forward = pygame.Vector2(0, 1).rotate(self.rotation)
+        self.position += forward * PLAYER_SPEED * dt
+
+    def shoot(self):
+        player_shot = Shot(self.position.x, self.position.y)
+        player_shot.velocity = pygame.Vector2(0, 1).rotate(
+            self.rotation) * PLAYER_SHOOT_SPEED
+        self.timer = PLAYER_SHOOT_COOLDOWN
diff --git a/requirements.txt b/requirements.txt
new file mode 100644
index 0000000..5873083
--- /dev/null
+++ b/requirements.txt
@@ -0,0 +1 @@
+pygame==2.6.1
diff --git a/shot.py b/shot.py
new file mode 100644
index 0000000..41aa764
--- /dev/null
+++ b/shot.py
@@ -0,0 +1,14 @@
+import pygame
+from constants import SHOT_RADUIS
+from circleshape import CircleShape
+
+
+class Shot(CircleShape):
+    def __init__(self, x: int, y :int) -> None:
+        super().__init__(x, y, SHOT_RADUIS)
+
+    def draw(self, screen) -> None:
+        pygame.draw.circle(screen, "white", self.position, self.radius, 2)
+
+    def update(self, dt: int):
+        self.position += self.velocity * dt