diff --git a/dev.org b/dev.org
index a44fa61..a79a10a 100644
--- a/dev.org
+++ b/dev.org
@@ -4,6 +4,11 @@
 - A parser combinator library for Rust :: https://github.com/Marwes/combine
 - Parsing Expression Grammar (PEG) parser generator for Rust :: https://github.com/kevinmehall/rust-peg
 - General purpose parser :: https://pest.rs/
+* Considerations
+** Hashmaps
+*** DOS attack
+- https://www.anchor.com.au/blog/2012/12/how-to-explain-hash-dos-to-your-parents-by-using-cats/
+- https://en.wikipedia.org/wiki/Collision_attack
 
 * Resources
 ** Rust