diff --git a/src/Class/AttributeInfo.zig b/src/Class/AttributeInfo.zig
index 9e13aa0..3fd70ba 100644
--- a/src/Class/AttributeInfo.zig
+++ b/src/Class/AttributeInfo.zig
@@ -393,7 +393,10 @@ pub const AttributeInfo = union(enum) {
                         _ = try w.write("source_file:\n");
                         try source_file.indentedFormat(w, depth, indent + 1, constant_pool);
                     },
-                    //.source_debug_extension,
+                    .source_debug_extension => |attr| {
+                        try w.splatByteAll(' ', depth * indent);
+                        try w.print("debug_extension: {s}\n", .{ attr.debug_extension });
+                    },
                     //.line_number_table,
                     //.local_variable_table,
                     //.local_variable_type_table,