diff --git a/Cargo.toml b/Cargo.toml
index 7ec1bfc..f924931 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "markets"
-version = "0.3.0"
+version = "0.3.1"
 authors = ["Jonathan Strong <jonathan.strong@gmail.com>"]
 edition = "2018"
 description = "kind of like the http crate, except about tradeable markets"
diff --git a/src/crypto.rs b/src/crypto.rs
index eaa0990..5a811a6 100644
--- a/src/crypto.rs
+++ b/src/crypto.rs
@@ -39,10 +39,11 @@ macro_rules! t {
 /// which side of the transaction (buying or selling)
 /// a price/trade is
 ///
+#[repr(u8)]
 #[derive(Debug, PartialEq, Clone, Copy, Eq, Serialize)]
 pub enum Side { 
-    Bid, 
-    Ask 
+    Bid = 1,
+    Ask = 2,
 }
 
 impl TryFrom<u8> for Side {