diff --git a/.jules/bolt.md b/.jules/bolt.md
new file mode 100644
index 00000000..5fb263fd
--- /dev/null
+++ b/.jules/bolt.md
@@ -0,0 +1,5 @@
+## 2024-05-30 - Optimize string concatenation
+
+**Learning:** Rust string iterators using `.collect::<Vec<_>>().join("")` allocate an unnecessary intermediate vector.
+
+**Action:** Replace this pattern with `.collect::<String>()` to bypass the intermediate vector allocation.
diff --git a/xdk-lib/src/casing.rs b/xdk-lib/src/casing.rs
index 6463487e..bd04c567 100644
--- a/xdk-lib/src/casing.rs
+++ b/xdk-lib/src/casing.rs
@@ -29,11 +29,7 @@ impl Casing {
                     result
                 }
             }
-            Casing::Pascal => words
-                .iter()
-                .map(|w| pascal_case(w))
-                .collect::<Vec<_>>()
-                .join(""),
+            Casing::Pascal => words.iter().map(|w| pascal_case(w)).collect::<String>(),
             Casing::Kebab => words.join("-").to_lowercase(),
             Casing::ScreamingSnake => words.join("_").to_uppercase(),
         }
@@ -118,6 +114,6 @@ pub fn camel_case(value: &str) -> String {
     let mut chars = pascal.chars();
     match chars.next() {
         None => String::new(),
-        Some(first) => first.to_lowercase().collect::<String>() + chars.as_str(),
+        Some(first) => first.to_lowercase().to_string() + chars.as_str(),
     }
 }