diff --git a/.dir-locals.el b/.dir-locals.el
index 5481334..273bf42 100644
--- a/.dir-locals.el
+++ b/.dir-locals.el
@@ -2,8 +2,9 @@
 
 ((clojure-mode
   . ((cider-clojure-cli-parameters . "-M:common:dev")
-     (cider-inject-dependencies-at-jack-in . nil)
-     (eval
+     (cider-inject-dependencies-at-jack-in . nil)))
+ (nil
+  . ((eval
       . (progn
           (unless (fboundp 'clj-watch)
             (load (expand-file-name
@@ -20,12 +21,18 @@
             (interactive)
             (cider-interactive-eval "(engine/clear-error!)"))
 
+          (defun clj-game-reload-config ()
+            "Re-read config-path and re-init the running game's state from it."
+            (interactive)
+            (cider-interactive-eval "(engine/reload-config!)"))
+
           (unless (boundp 'clj-game-mode-map)
             (defvar clj-game-mode-map
               (let ((m (make-sparse-keymap)))
-                (define-key m (kbd "C-c C-w") #'clj-watch)
-                (define-key m (kbd "C-c C-M-r") #'clj-game-run-main)
-                (define-key m (kbd "C-c C-M-e") #'clj-game-clear-error)
+                (define-key m (kbd "C-c g w") #'clj-watch)
+                (define-key m (kbd "C-c g r") #'clj-game-run-main)
+                (define-key m (kbd "C-c g e") #'clj-game-clear-error)
+                (define-key m (kbd "C-c g c") #'clj-game-reload-config)
                 m)))
 
           (unless (fboundp 'clj-game-mode)
@@ -34,4 +41,4 @@
               :lighter " Game"
               :keymap clj-game-mode-map))
 
-          (clj-game-mode 1))))))
+          (clj-game-mode 1)))))))
diff --git a/.gitignore b/.gitignore
index 613c299..f3e5100 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,2 +1,3 @@
 /.cpcache/
 /.nrepl-port
+/source-assets/
diff --git a/deps.edn b/deps.edn
index bf3ff27..f614b80 100644
--- a/deps.edn
+++ b/deps.edn
@@ -7,9 +7,10 @@
   {:jvm-opts ["--enable-native-access=ALL-UNNAMED"
               "-Draylib.path=/home/joe/.local/bin/odin/vendor/raylib/linux/libraylib.so.600"]}
   :run
-  {:jvm-opts  ["--enable-native-access=ALL-UNNAMED"
-               "-Draylib.path=/home/joe/.local/bin/odin/vendor/raylib/linux/libraylib.so.600"]
-   :main-opts ["-m" "game"]}
+  {:main-opts ["-m" "game"]}
+
+  :sprite-atlas
+  {:main-opts ["-m" "sprite-atlas"]}
 
   :dev
   {:extra-deps {nrepl/nrepl       {:mvn/version "1.7.0"}
diff --git a/src/engine.clj b/src/engine.clj
index 0a46bcb..a813703 100644
--- a/src/engine.clj
+++ b/src/engine.clj
@@ -5,30 +5,39 @@
    [watch :as w]))
 
 (defonce ^:private last-error (atom nil))
+(defonce ^:private game-state (atom nil))
+(defonce ^:private game-config (atom nil))
 
-(defn clear-error!
-  "Call from the REPL to resume the loop after an error froze it."
-  []
+(defn clear-error! []
   (reset! last-error nil))
 
+(defn reload-config! []
+  (try
+    (swap! game-config #(assoc % :config (edn/read-string (slurp (:config-path %)))))
+    (catch Exception e
+      (println e))))
+
 (defn run-game!
   [{:keys [title width height config-path init input update draw watch-fn]
     :or   {title "Untitled" width 1200 height 900 watch-fn (constantly nil)}}]
   (rl/set-trace-log-level! rl/log-warning)
   (rl/init-window! width height title)
   (rl/set-target-fps! 60)
-  (let [state (atom (init (edn/read-string (slurp config-path))))]
+  (let [config (edn/read-string (slurp config-path))]
+    (reset! game-config {:config-path config-path :config config})
+    (reset! game-state (init config))
     (while (not (rl/window-should-close?))
       (if @last-error
         (Thread/sleep 50)
-        (rl/with-drawing!
-          (try
-            (swap! state input)
-            (swap! state update)
-            (draw @state)
-            (w/watch! (watch-fn @state))
-            (catch Throwable t
-              (println t)
-              (reset! last-error t)
-              (w/watch! (merge (watch-fn @state) {:error t})))))))
+        (let [config (:config @game-config)]
+          (rl/with-drawing!
+            (try
+              (swap! game-state #(input config %))
+              (swap! game-state #(update config %))
+              (draw config @game-state)
+              (w/watch! (watch-fn config @game-state))
+              (catch Throwable t
+                (println t)
+                (reset! last-error t)
+                (w/watch! (merge (watch-fn config @game-state) {:error t}))))))))
     (rl/close-window!)))
diff --git a/src/game.clj b/src/game.clj
index 8127d70..925197f 100644
--- a/src/game.clj
+++ b/src/game.clj
@@ -9,18 +9,18 @@
 (defn init-game [config]
   {:color-idx 0})
 
-(defn handle-game-input [game]
+(defn handle-game-input [config game]
   (when (rl/key-pressed? rl/key-r))
   (when (rl/mouse-button-down? rl/mouse-button-left))
   game)
 
-(defn update-game [game]
+(defn update-game [config game]
   game)
 
-(defn draw-game [game]
+(defn draw-game [config game]
   (rl/clear-background!* rl/cornflower-blue))
 
-(defn watch-game [game]
+(defn watch-game [config game]
   {:color-idx (:color-idx game)})
 
 (defn -main [& _args]
diff --git a/src/user.clj b/src/user.clj
new file mode 100644
index 0000000..c54c2c7
--- /dev/null
+++ b/src/user.clj
@@ -0,0 +1,2 @@
+(ns user
+  (:require [game]))