diff --git a/Cargo.lock b/Cargo.lock
index da16aa4..e6579aa 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -3622,6 +3622,8 @@ dependencies = [
  "bevy",
  "bevy_aseprite_ultra",
  "bevy_dev_tools",
+ "serde",
+ "serde_json",
 ]
 
 [[package]]
diff --git a/Cargo.toml b/Cargo.toml
index c72a83a..529d8e9 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -17,3 +17,5 @@ lto = "thin"
 bevy = "0.17.2"
 bevy_aseprite_ultra = "0.7.0"
 bevy_dev_tools = "0.17.2"
+serde = { version = "1.0", features = ["derive"] }
+serde_json = "1.0"
diff --git a/assets/config.json b/assets/config.json
new file mode 100644
index 0000000..fa9d4aa
--- /dev/null
+++ b/assets/config.json
@@ -0,0 +1,5 @@
+{
+  "grid_width": 10,
+  "grid_height": 10,
+  "pom_speed": 2
+}
diff --git a/flake.nix b/flake.nix
index e054130..e0e87c2 100644
--- a/flake.nix
+++ b/flake.nix
@@ -24,10 +24,10 @@
 
       rust-toolchain = with fenix.packages.${system};
         combine [
-          beta.rustc
-          beta.cargo
-          beta.rust-src
-          beta.rust-analyzer
+          stable.rustc
+          stable.cargo
+          stable.rust-src
+          stable.rust-analyzer
         ];
 
       bevyDeps = with pkgs; [
diff --git a/src/config.rs b/src/config.rs
new file mode 100644
index 0000000..979ccb8
--- /dev/null
+++ b/src/config.rs
@@ -0,0 +1,17 @@
+use bevy::prelude::*;
+use serde::Deserialize;
+use std::fs::File;
+use std::io::BufReader;
+
+#[derive(Resource, Deserialize, Debug)]
+pub struct GameConfig {
+    pub grid_width: u32,
+    pub grid_height: u32,
+    pub pom_speed: f32,
+}
+
+pub fn read_config() -> Option<GameConfig> {
+    let file = File::open("assets/config.json").ok()?;
+    let reader = BufReader::new(file);
+    serde_json::from_reader(reader).ok()
+}
diff --git a/src/lib.rs b/src/lib.rs
index c45b318..4c07870 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -1,4 +1,5 @@
 pub mod components;
+pub mod config;
 pub mod errors;
 pub mod messages;
 pub mod plugins;
diff --git a/src/main.rs b/src/main.rs
index 12401b6..c045bd4 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,9 +1,12 @@
 use bevy::prelude::*;
 use bevy_aseprite_ultra::prelude::*;
 use bevy_dev_tools::fps_overlay::*;
+use pomomon_garden::config::read_config;
 use pomomon_garden::plugins;
 
 fn main() {
+    let config = read_config().expect("Error reading config");
+
     App::new()
         .add_plugins((
             DefaultPlugins.set(ImagePlugin::default_nearest()),
@@ -29,5 +32,6 @@ fn main() {
             plugins::PomPlugin,
             plugins::InputPlugin,
         ))
+        .insert_resource(config)
         .run();
 }
diff --git a/src/plugins/grid.rs b/src/plugins/grid.rs
index d8a4f75..d6e6026 100644
--- a/src/plugins/grid.rs
+++ b/src/plugins/grid.rs
@@ -1,16 +1,19 @@
 use crate::{
     components::tile::{Grid, Tile, TileState},
+    config::GameConfig,
     states::AppState,
 };
 use bevy::prelude::*;
 use bevy_aseprite_ultra::prelude::AseSlice;
 
 pub const TILE_SIZE: f32 = 32.0;
-pub const GRID_WIDTH: u32 = 10;
-pub const GRID_HEIGHT: u32 = 10;
 
-pub const GRID_START_X: f32 = -(GRID_WIDTH as f32 * TILE_SIZE) / 2.0 + TILE_SIZE / 2.0;
-pub const GRID_START_Y: f32 = -(GRID_HEIGHT as f32 * TILE_SIZE) / 2.0 + TILE_SIZE / 2.0;
+pub fn grid_start_x(grid_width: u32) -> f32 {
+    -(grid_width as f32 * TILE_SIZE) / 2.0 + TILE_SIZE / 2.0
+}
+pub fn grid_start_y(grid_height: u32) -> f32 {
+    -(grid_height as f32 * TILE_SIZE) / 2.0 + TILE_SIZE / 2.0
+}
 
 pub struct GridPlugin;
 
@@ -26,13 +29,15 @@ impl Plugin for GridPlugin {
     }
 }
 
-fn setup(mut commands: Commands, asset_server: Res<AssetServer>) {
-    let mut tiles = Vec::with_capacity(GRID_WIDTH as usize);
+fn setup(mut commands: Commands, asset_server: Res<AssetServer>, config: Res<GameConfig>) {
+    let grid_width = config.grid_width;
+    let grid_height = config.grid_height;
+    let mut tiles = Vec::with_capacity(grid_width as usize);
 
-    for x in 0..GRID_WIDTH {
-        let mut column = Vec::with_capacity(GRID_HEIGHT as usize);
+    for x in 0..grid_width {
+        let mut column = Vec::with_capacity(grid_height as usize);
 
-        for y in 0..GRID_HEIGHT {
+        for y in 0..grid_height {
             let tile_entity = commands
                 .spawn((
                     Tile { x, y },
@@ -42,7 +47,13 @@ fn setup(mut commands: Commands, asset_server: Res<AssetServer>) {
                         aseprite: asset_server.load("tiles/tile-unclaimed.aseprite"),
                     },
                     Sprite::default(),
-                    Transform::from_translation(grid_to_world_coords(x, y, None)),
+                    Transform::from_translation(grid_to_world_coords(
+                        x,
+                        y,
+                        None,
+                        grid_width,
+                        grid_height,
+                    )),
                 ))
                 .id();
             column.push(tile_entity);
@@ -51,8 +62,8 @@ fn setup(mut commands: Commands, asset_server: Res<AssetServer>) {
     }
 
     commands.insert_resource(Grid {
-        width: GRID_WIDTH,
-        height: GRID_HEIGHT,
+        width: grid_width,
+        height: grid_height,
         tiles,
     });
 }
@@ -84,27 +95,36 @@ fn update_tile_colors(
     }
 }
 
-pub fn world_to_grid_coords(world_pos: Vec3) -> (u32, u32) {
-    let x = ((world_pos.x - GRID_START_X + TILE_SIZE / 2.0) / TILE_SIZE).floor();
-    let y = ((world_pos.y - GRID_START_Y + TILE_SIZE / 2.0) / TILE_SIZE).floor();
+pub fn world_to_grid_coords(world_pos: Vec3, grid_width: u32, grid_height: u32) -> (u32, u32) {
+    let start_x = grid_start_x(grid_width);
+    let start_y = grid_start_y(grid_height);
+
+    let x = ((world_pos.x - start_x + TILE_SIZE / 2.0) / TILE_SIZE).floor();
+    let y = ((world_pos.y - start_y + TILE_SIZE / 2.0) / TILE_SIZE).floor();
 
     let mut x_u32 = x as u32;
     let mut y_u32 = y as u32;
 
-    if x_u32 >= GRID_WIDTH {
-        x_u32 = GRID_WIDTH - 1;
+    if x_u32 >= grid_width {
+        x_u32 = grid_width - 1;
     }
-    if y_u32 >= GRID_HEIGHT {
-        y_u32 = GRID_HEIGHT - 1;
+    if y_u32 >= grid_height {
+        y_u32 = grid_height - 1;
     }
 
     (x_u32, y_u32)
 }
 
-pub fn grid_to_world_coords(grid_x: u32, grid_y: u32, z: Option<f32>) -> Vec3 {
+pub fn grid_to_world_coords(
+    grid_x: u32,
+    grid_y: u32,
+    z: Option<f32>,
+    grid_width: u32,
+    grid_height: u32,
+) -> Vec3 {
     Vec3::new(
-        GRID_START_X + grid_x as f32 * TILE_SIZE,
-        GRID_START_Y + grid_y as f32 * TILE_SIZE,
+        grid_start_x(grid_width) + grid_x as f32 * TILE_SIZE,
+        grid_start_y(grid_height) + grid_y as f32 * TILE_SIZE,
         z.unwrap_or(0.0),
     )
 }
diff --git a/src/plugins/input.rs b/src/plugins/input.rs
index c16b1ad..1a9f77b 100644
--- a/src/plugins/input.rs
+++ b/src/plugins/input.rs
@@ -3,6 +3,7 @@ use bevy::prelude::*;
 use bevy::window::PrimaryWindow;
 
 use crate::components::tile::{Grid, TileState};
+use crate::config::GameConfig;
 use crate::messages::{InteractStartMessage, InvalidMoveMessage, MoveMessage};
 use crate::plugins::grid::world_to_grid_coords;
 use crate::states::AppState;
@@ -28,6 +29,7 @@ fn move_click(
     mouse_btn: Res<ButtonInput<MouseButton>>,
     window: Single<&Window, With<PrimaryWindow>>,
     camera: Single<(&Camera, &GlobalTransform), With<Camera2d>>,
+    config: Res<GameConfig>,
 ) {
     if mouse_btn.just_pressed(MouseButton::Right) {
         let (cam, cam_transform) = *camera;
@@ -38,7 +40,7 @@ fn move_click(
         let Ok(world_pos) = cam.viewport_to_world(cam_transform, cursor_pos) else {
             return;
         };
-        let (x, y) = world_to_grid_coords(world_pos.origin);
+        let (x, y) = world_to_grid_coords(world_pos.origin, config.grid_width, config.grid_height);
 
         println!("Move Click: ({}, {})", x, y);
         move_messages.write(MoveMessage { x, y });
@@ -50,6 +52,7 @@ fn interact_click(
     mouse_btn: Res<ButtonInput<MouseButton>>,
     window: Single<&Window, With<PrimaryWindow>>,
     camera: Single<(&Camera, &GlobalTransform), With<Camera2d>>,
+    config: Res<GameConfig>,
     // for debug
     grid: ResMut<Grid>,
     tile_query: Query<&mut TileState>,
@@ -63,7 +66,7 @@ fn interact_click(
         let Ok(world_pos) = cam.viewport_to_world(cam_transform, cursor_pos) else {
             return;
         };
-        let (x, y) = world_to_grid_coords(world_pos.origin);
+        let (x, y) = world_to_grid_coords(world_pos.origin, config.grid_width, config.grid_height);
 
         println!("Interact Click: ({}, {})", x, y);
         interact_messages.write(InteractStartMessage { x, y });
diff --git a/src/plugins/pom.rs b/src/plugins/pom.rs
index 71eefda..c096822 100644
--- a/src/plugins/pom.rs
+++ b/src/plugins/pom.rs
@@ -1,14 +1,13 @@
 use crate::components::pom::{GridPosition, MovingState, PathQueue, Pom};
 use crate::components::tile::{Grid, TileState};
+use crate::config::GameConfig;
 use crate::messages::{InvalidMoveMessage, MoveMessage};
-use crate::plugins::grid::{GRID_WIDTH, grid_to_world_coords};
+use crate::plugins::grid::{TILE_SIZE, grid_to_world_coords};
 use crate::states::*;
 use crate::utils::pathfinding::find_path;
 use bevy::prelude::*;
 use bevy_aseprite_ultra::prelude::*;
 
-const MOVE_SPEED: f32 = 2.0 * GRID_WIDTH as f32;
-
 pub struct PomPlugin;
 
 impl Plugin for PomPlugin {
@@ -23,7 +22,7 @@ impl Plugin for PomPlugin {
     }
 }
 
-fn setup(mut commands: Commands, asset_server: Res<AssetServer>) {
+fn setup(mut commands: Commands, asset_server: Res<AssetServer>, config: Res<GameConfig>) {
     commands.spawn((
         Pom,
         GridPosition { x: 0, y: 0 },
@@ -34,7 +33,13 @@ fn setup(mut commands: Commands, asset_server: Res<AssetServer>) {
             animation: Animation::tag("sleep-sit-start").with_repeat(AnimationRepeat::Loop),
         },
         Sprite::default(),
-        Transform::from_translation(grid_to_world_coords(0, 0, Some(1.0))),
+        Transform::from_translation(grid_to_world_coords(
+            0,
+            0,
+            Some(1.0),
+            config.grid_width,
+            config.grid_height,
+        )),
     ));
 }
 
@@ -82,12 +87,20 @@ fn move_pom(
         &mut PathQueue,
         &mut MovingState,
     )>,
+    config: Res<GameConfig>,
 ) {
     let dt = time.delta_secs();
+    let move_speed = config.pom_speed * TILE_SIZE;
 
     for (mut transform, mut grid_pos, mut path_queue, mut moving_state) in query.iter_mut() {
         if let Some(&target) = path_queue.steps.front() {
-            let target_pos = grid_to_world_coords(target.0, target.1, Some(1.0));
+            let target_pos = grid_to_world_coords(
+                target.0,
+                target.1,
+                Some(1.0),
+                config.grid_width,
+                config.grid_height,
+            );
             let distance = transform.translation.distance(target_pos);
 
             let dx = target.0 as i32 - grid_pos.x as i32;
@@ -100,14 +113,14 @@ fn move_pom(
                 _ => (),
             }
 
-            if distance < MOVE_SPEED * dt {
+            if distance < move_speed * dt {
                 transform.translation = target_pos;
                 grid_pos.x = target.0;
                 grid_pos.y = target.1;
                 path_queue.steps.pop_front();
             } else {
                 let direction = (target_pos - transform.translation).normalize();
-                transform.translation += direction * MOVE_SPEED * dt;
+                transform.translation += direction * move_speed * dt;
             }
         } else {
             *moving_state = MovingState::Idle;