diff --git a/kilo_editor.nyash b/kilo_editor.nyash
new file mode 100644
index 00000000..c5c32d0d
--- /dev/null
+++ b/kilo_editor.nyash
@@ -0,0 +1,237 @@
+// Kilo Text Editor - Memory Management Stress Test
+// This tests Box method calls and memory management extensively
+
+// KiloEditor Box - stores editor state
+box KiloEditor {
+    init { lines, cursor_row, cursor_col, filename, dirty }
+    
+    // Initialize empty editor
+    init_empty() {
+        me.lines = new ArrayBox()
+        me.cursor_row = 0  
+        me.cursor_col = 0
+        me.filename = ""
+        me.dirty = false
+        
+        // Start with one empty line
+        local empty_line
+        empty_line = new StringBox()
+        me.lines.push(empty_line)
+    }
+    
+    // Get current line as StringBox
+    get_current_line() {
+        return me.lines.get(me.cursor_row)
+    }
+    
+    // Insert character at cursor position
+    insert_char(ch) {
+        local current_line
+        local left_part
+        local right_part  
+        local new_line
+        
+        current_line = me.get_current_line()
+        
+        // Split line at cursor position
+        left_part = current_line.substring(0, me.cursor_col)
+        right_part = current_line.substring(me.cursor_col, current_line.length())
+        
+        // Create new line with inserted character
+        new_line = left_part.concat(ch).concat(right_part)
+        
+        // Replace line in array
+        me.lines.set(me.cursor_row, new_line)
+        
+        // Move cursor
+        me.cursor_col = me.cursor_col + 1
+        me.dirty = true
+    }
+    
+    // Delete character before cursor  
+    delete_char() {
+        local current_line
+        local left_part
+        local right_part
+        local new_line
+        
+        if me.cursor_col > 0 {
+            current_line = me.get_current_line()
+            
+            // Split line at cursor position
+            left_part = current_line.substring(0, me.cursor_col - 1)
+            right_part = current_line.substring(me.cursor_col, current_line.length())
+            
+            // Create new line without deleted character
+            new_line = left_part.concat(right_part)
+            
+            // Replace line in array
+            me.lines.set(me.cursor_row, new_line)
+            
+            // Move cursor back
+            me.cursor_col = me.cursor_col - 1
+            me.dirty = true
+        }
+    }
+    
+    // Insert new line at cursor
+    insert_newline() {
+        local current_line
+        local left_part
+        local right_part
+        
+        current_line = me.get_current_line()
+        
+        // Split current line
+        left_part = current_line.substring(0, me.cursor_col)
+        right_part = current_line.substring(me.cursor_col, current_line.length())
+        
+        // Update current line with left part
+        me.lines.set(me.cursor_row, left_part)
+        
+        // Insert new line with right part
+        me.lines.insert(me.cursor_row + 1, right_part)
+        
+        // Move cursor to start of new line
+        me.cursor_row = me.cursor_row + 1
+        me.cursor_col = 0
+        me.dirty = true
+    }
+    
+    // Get editor stats for memory testing
+    get_stats() {
+        local stats
+        local total_chars
+        local line_count
+        local i
+        local current_line
+        
+        stats = new StringBox()
+        line_count = me.lines.length()
+        total_chars = 0
+        
+        // Count total characters across all lines
+        i = 0
+        loop(i < line_count) {
+            current_line = me.lines.get(i)
+            total_chars = total_chars + current_line.length()
+            i = i + 1
+        }
+        
+        stats = stats.concat("Lines: ").concat(line_count.toString())
+        stats = stats.concat(" | Chars: ").concat(total_chars.toString())
+        stats = stats.concat(" | Cursor: ").concat(me.cursor_row.toString())
+        stats = stats.concat(",").concat(me.cursor_col.toString())
+        
+        return stats
+    }
+    
+    // Render editor content (simplified)
+    render() {
+        local line_count
+        local i
+        local current_line
+        local line_display
+        
+        print("=== Kilo Editor ===")
+        
+        line_count = me.lines.length()
+        i = 0
+        
+        loop(i < line_count) {
+            current_line = me.lines.get(i)
+            
+            // Create line display with line number
+            line_display = (i + 1).toString().concat(": ").concat(current_line.toString())
+            
+            // Mark current line with cursor
+            if i == me.cursor_row {
+                line_display = line_display.concat(" <-- cursor at col ").concat(me.cursor_col.toString())
+            }
+            
+            print(line_display)
+            i = i + 1
+        }
+        
+        print("---")
+        print(me.get_stats())
+        print("===================")
+    }
+}
+
+// Test the kilo editor with intensive Box operations
+local editor
+local test_char
+local i
+
+print("Starting Kilo Editor Memory Test...")
+
+// Create editor
+editor = new KiloEditor()
+editor.init_empty()
+
+print("Initial state:")
+editor.render()
+
+// Test 1: Insert multiple characters (stress StringBox creation)
+print("Test 1: Inserting 'Hello World'...")
+editor.insert_char("H")
+editor.insert_char("e")
+editor.insert_char("l")
+editor.insert_char("l")
+editor.insert_char("o")
+editor.insert_char(" ")
+editor.insert_char("W")
+editor.insert_char("o")
+editor.insert_char("r")
+editor.insert_char("l")
+editor.insert_char("d")
+
+editor.render()
+
+// Test 2: Insert new lines (stress ArrayBox operations)
+print("Test 2: Adding new lines...")
+editor.insert_newline()
+editor.insert_char("L")
+editor.insert_char("i")
+editor.insert_char("n")
+editor.insert_char("e")
+editor.insert_char(" ")
+editor.insert_char("2")
+
+editor.insert_newline()
+editor.insert_char("L")
+editor.insert_char("i")
+editor.insert_char("n")
+editor.insert_char("e")
+editor.insert_char(" ")
+editor.insert_char("3")
+
+editor.render()
+
+// Test 3: Delete operations (memory cleanup test)
+print("Test 3: Testing deletions...")
+editor.delete_char()
+editor.delete_char()
+editor.delete_char()
+
+editor.render()
+
+// Test 4: Intensive operations for memory stress
+print("Test 4: Memory stress test - 50 operations...")
+i = 0
+loop(i < 10) {
+    editor.insert_char("X")
+    editor.delete_char()
+    editor.insert_char("Y")
+    editor.delete_char()
+    editor.insert_char("Z")
+    i = i + 1
+}
+
+editor.render()
+
+print("Kilo Editor Memory Test Complete!")
+local final_stats
+final_stats = editor.get_stats()
+print(final_stats)
\ No newline at end of file
diff --git a/kilo_simple_test.nyash b/kilo_simple_test.nyash
new file mode 100644
index 00000000..eb5e4bde
--- /dev/null
+++ b/kilo_simple_test.nyash
@@ -0,0 +1,79 @@
+// Simple Kilo Editor Test - Step by step validation
+// Test basic Box operations before full editor
+
+local s1
+local s2
+local s3
+local result
+
+print("=== StringBox Methods Test ===")
+
+// Test basic StringBox operations
+s1 = ""  // Create empty string instead of new StringBox()
+print("Created empty StringBox")
+
+s2 = "Hello"
+print("String length test:")
+result = s2.length()
+print(result)
+
+print("String substring test:")
+result = s2.substring(1, 4)
+print(result)
+
+print("String concat test:")
+s3 = " World"
+result = s2.concat(s3)
+print(result)
+
+print("=== ArrayBox Methods Test ===")
+
+local arr
+local item
+local len
+
+arr = new ArrayBox()
+print("Created empty ArrayBox")
+
+len = arr.length()
+print("Array length:")
+print(len)
+
+print("=== Basic Editor Component Test ===")
+
+// Test a simple editor component without full complexity
+box SimpleEditor {
+    init { text, cursor }
+    
+    init_empty() {
+        me.text = ""
+        me.cursor = 0
+    }
+    
+    append_char(ch) {
+        me.text = me.text.concat(ch)
+        me.cursor = me.cursor + 1
+    }
+    
+    get_text() {
+        return me.text
+    }
+    
+    get_cursor() {
+        return me.cursor
+    }
+}
+
+local editor
+editor = new SimpleEditor()
+editor.init_empty()
+
+print("Testing simple editor:")
+editor.append_char("H")
+editor.append_char("i")
+
+print("Editor text:")
+print(editor.get_text())
+
+print("Editor cursor:")
+print(editor.get_cursor())
\ No newline at end of file
diff --git a/src/backend/vm.rs b/src/backend/vm.rs
index 42b07a2a..3a3e608f 100644
--- a/src/backend/vm.rs
+++ b/src/backend/vm.rs
@@ -335,10 +335,36 @@ impl VM {
                 Ok(ControlFlow::Continue)
             },
             
-            MirInstruction::NewBox { dst, box_type: _, args: _ } => {
-                // For now, new box creates a placeholder string value
-                // TODO: Implement proper box creation
-                self.values.insert(*dst, VMValue::String("NewBox".to_string()));
+            MirInstruction::NewBox { dst, box_type, args: _ } => {
+                // Implement basic box creation for common types
+                let result = match box_type.as_str() {
+                    "StringBox" => {
+                        // Create empty StringBox - in real implementation would use args
+                        let string_box = Box::new(StringBox::new(""));
+                        VMValue::from_nyash_box(string_box)
+                    },
+                    "ArrayBox" => {
+                        // Create empty ArrayBox - in real implementation would use args
+                        let array_box = Box::new(crate::boxes::array::ArrayBox::new());
+                        VMValue::from_nyash_box(array_box)
+                    },
+                    "IntegerBox" => {
+                        // Create IntegerBox with default value
+                        let int_box = Box::new(IntegerBox::new(0));
+                        VMValue::from_nyash_box(int_box)
+                    },
+                    "BoolBox" => {
+                        // Create BoolBox with default value
+                        let bool_box = Box::new(BoolBox::new(false));
+                        VMValue::from_nyash_box(bool_box)
+                    },
+                    _ => {
+                        // For unknown types, create a placeholder string
+                        VMValue::String(format!("NewBox[{}]", box_type))
+                    }
+                };
+                
+                self.values.insert(*dst, result);
                 Ok(ControlFlow::Continue)
             },
             
@@ -630,6 +656,39 @@ impl VM {
                 "toString" => {
                     return Ok(Box::new(StringBox::new(string_box.value.clone())));
                 },
+                "substring" => {
+                    // substring(start, end) - simplified implementation
+                    if _args.len() >= 2 {
+                        if let (Some(start_box), Some(end_box)) = (_args.get(0), _args.get(1)) {
+                            if let (Some(start_int), Some(end_int)) = (
+                                start_box.as_any().downcast_ref::<IntegerBox>(),
+                                end_box.as_any().downcast_ref::<IntegerBox>()
+                            ) {
+                                let start = start_int.value.max(0) as usize;
+                                let end = end_int.value.max(0) as usize;
+                                let len = string_box.value.len();
+                                
+                                if start <= len {
+                                    let end_idx = end.min(len);
+                                    if start <= end_idx {
+                                        let substr = &string_box.value[start..end_idx];
+                                        return Ok(Box::new(StringBox::new(substr)));
+                                    }
+                                }
+                            }
+                        }
+                    }
+                    return Ok(Box::new(StringBox::new(""))); // Return empty string on error
+                },
+                "concat" => {
+                    // concat(other) - concatenate with another string
+                    if let Some(other_box) = _args.get(0) {
+                        let other_str = other_box.to_string_box().value;
+                        let result = string_box.value.clone() + &other_str;
+                        return Ok(Box::new(StringBox::new(result)));
+                    }
+                    return Ok(Box::new(StringBox::new(string_box.value.clone())));
+                },
                 _ => return Ok(Box::new(VoidBox::new())), // Unsupported method
             }
         }
@@ -657,6 +716,46 @@ impl VM {
             }
         }
         
+        // ArrayBox methods - needed for kilo editor
+        if let Some(array_box) = box_value.as_any().downcast_ref::<crate::boxes::array::ArrayBox>() {
+            match method {
+                "length" | "len" => {
+                    let items = array_box.items.lock().unwrap();
+                    return Ok(Box::new(IntegerBox::new(items.len() as i64)));
+                },
+                "get" => {
+                    // get(index) - get element at index
+                    if let Some(index_box) = _args.get(0) {
+                        if let Some(index_int) = index_box.as_any().downcast_ref::<IntegerBox>() {
+                            let items = array_box.items.lock().unwrap();
+                            let index = index_int.value as usize;
+                            if index < items.len() {
+                                return Ok(items[index].clone_box());
+                            }
+                        }
+                    }
+                    return Ok(Box::new(VoidBox::new())); // Return void for out of bounds
+                },
+                "set" => {
+                    // set(index, value) - simplified implementation
+                    // Note: This is a read-only operation in the VM for now
+                    // In a real implementation, we'd need mutable access
+                    return Ok(Box::new(VoidBox::new()));
+                },
+                "push" => {
+                    // push(value) - simplified implementation
+                    // Note: This is a read-only operation in the VM for now
+                    return Ok(Box::new(VoidBox::new()));
+                },
+                "insert" => {
+                    // insert(index, value) - simplified implementation
+                    // Note: This is a read-only operation in the VM for now
+                    return Ok(Box::new(VoidBox::new()));
+                },
+                _ => return Ok(Box::new(VoidBox::new())), // Unsupported method
+            }
+        }
+        
         // Default: return void for any unrecognized box type or method
         Ok(Box::new(VoidBox::new()))
     }