diff --git a/lyra-ecs/src/system/graph.rs b/lyra-ecs/src/system/graph.rs
index 5c32e84..68c6651 100644
--- a/lyra-ecs/src/system/graph.rs
+++ b/lyra-ecs/src/system/graph.rs
@@ -106,7 +106,7 @@ impl GraphExecutor {
 
 #[cfg(test)]
 mod tests {
-    use crate::{View, QueryBorrow, tests::Vec2, IntoSystem, world::World, Resource};
+    use crate::{View, QueryBorrow, tests::Vec2, IntoSystem, world::World, Resource, ResourceMut};
 
     use super::GraphExecutor;
 
@@ -118,36 +118,48 @@ mod tests {
 
         let mut exec = GraphExecutor::new();
 
-        /// TODO:
-        /// * Implement FnArg for World
-        /// * Implement ResourceMut
-
-        let a_system = |view: View<(QueryBorrow<Vec2>, Resource<Vec<String>>)>| -> anyhow::Result<()> {
+        let a_system = |view: View<ResourceMut<Vec<String>>>| -> anyhow::Result<()> {
             println!("System 'a' ran!");
             
-            let order = view.into_iter().next();
+            let mut order = view.into_iter().next().unwrap();
+            order.push("a".to_string());
 
             Ok(())
         };
 
-        let b_system = |view: View<QueryBorrow<Vec2>>| -> anyhow::Result<()> {
+        let b_system = |view: View<ResourceMut<Vec<String>>>| -> anyhow::Result<()> {
             println!("System 'b' ran!");
 
+            let mut order = view.into_iter().next().unwrap();
+            order.push("b".to_string());
+
             Ok(())
         };
 
-        let c_system = |view: View<QueryBorrow<Vec2>>| -> anyhow::Result<()> {
+        let c_system = |view: View<ResourceMut<Vec<String>>>| -> anyhow::Result<()> {
             println!("System 'c' ran!");
 
+            let mut order = view.into_iter().next().unwrap();
+            order.push("c".to_string());
+
             Ok(())
         };
 
-        exec.insert_system("c", c_system.into_system(), &[]);
+        // inserted into the graph out of order...
+        exec.insert_system("c", c_system.into_system(), &["b"]);
         exec.insert_system("a", a_system.into_system(), &[]);
         exec.insert_system("b", b_system.into_system(), &["a"]);
 
-        
         exec.execute(&world, true).unwrap();
         println!("Executed systems");
+
+        let order = world.get_resource::<Vec<String>>();
+        let mut order_iter = order.iter();
+
+        // ... but still executed in order
+        assert_eq!(order_iter.next().unwrap().clone(), "a".to_string());
+        assert_eq!(order_iter.next().unwrap().clone(), "b".to_string());
+        assert_eq!(order_iter.next().unwrap().clone(), "c".to_string());
+        println!("Systems executed in order");
     }
 }
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