diff --git a/battlesnake/Cargo.toml b/battlesnake/Cargo.toml
index fe0daa0..734fdb0 100644
--- a/battlesnake/Cargo.toml
+++ b/battlesnake/Cargo.toml
@@ -19,7 +19,7 @@ nursery = "warn"
 # server
 tokio = { version = "1.43", features = ["net", "macros", "rt-multi-thread"] }
 axum = { version = "0.8", features = ["http2", "multipart", "ws"] }
-serde = { version = "1.0", features = ["derive"] }
+serde = { version = "1.0", features = ["derive", "rc"] }
 
 # logging
 log = "0.4"
diff --git a/battlesnake/benches/simulation.rs b/battlesnake/benches/simulation.rs
index 5316314..1b5c2d4 100644
--- a/battlesnake/benches/simulation.rs
+++ b/battlesnake/benches/simulation.rs
@@ -1,4 +1,7 @@
-use std::sync::atomic::{AtomicU32, Ordering};
+use std::sync::{
+    atomic::{AtomicU32, Ordering},
+    Arc,
+};
 
 use criterion::{black_box, criterion_group, criterion_main, Bencher, BenchmarkId, Criterion};
 
@@ -9,7 +12,7 @@ use battlesnake::types::{
 };
 
 fn create_start_snake(coord: Coord) -> Battlesnake {
-    let id = format!("{coord:?}");
+    let id: Arc<str> = format!("{coord:?}").into();
     Battlesnake {
         id: id.clone(),
         name: id.clone(),
@@ -18,7 +21,7 @@ fn create_start_snake(coord: Coord) -> Battlesnake {
         latency: "0".into(),
         head: coord,
         length: 3,
-        shout: String::new(),
+        shout: None,
         squad: id,
     }
 }
diff --git a/battlesnake/src/types/simulation.rs b/battlesnake/src/types/simulation.rs
index df53c79..d2d8397 100644
--- a/battlesnake/src/types/simulation.rs
+++ b/battlesnake/src/types/simulation.rs
@@ -3,6 +3,7 @@ use std::{
     fmt::Display,
     num::NonZeroUsize,
     ops::{Deref, DerefMut},
+    sync::Arc,
 };
 
 use bitvec::prelude::*;
@@ -70,6 +71,7 @@ pub struct Board {
     free: SmallBitBox,
     snakes: Vec<Snake>,
     constrictor: bool,
+    id_map: Arc<[(u8, Arc<str>)]>,
 }
 
 impl From<&Request> for Board {
@@ -77,6 +79,18 @@ impl From<&Request> for Board {
         let width = value.board.width;
         let height = value.board.height;
         let fields = usize::from(width) * usize::from(height);
+        let id_map = value
+            .board
+            .snakes
+            .iter()
+            .enumerate()
+            .filter_map(|(i, snake)| {
+                u8::try_from(i)
+                    .inspect_err(|e| warn!("unable to convert id to u8: {e}"))
+                    .ok()
+                    .map(|i| (i, snake.id.clone()))
+            })
+            .collect::<Vec<_>>();
         let mut board = Self {
             width,
             height,
@@ -88,7 +102,8 @@ impl From<&Request> for Board {
             hazard: SmallBitBox::new(false, fields),
             free: SmallBitBox::new(true, fields),
             snakes: Vec::with_capacity(value.board.snakes.len()),
-            constrictor: value.game.ruleset.name == "constrictor",
+            constrictor: &*value.game.ruleset.name == "constrictor",
+            id_map: id_map.into(),
         };
 
         for &food in &value.board.food {
diff --git a/battlesnake/src/types/wire.rs b/battlesnake/src/types/wire.rs
index 214686b..7fe22c5 100644
--- a/battlesnake/src/types/wire.rs
+++ b/battlesnake/src/types/wire.rs
@@ -1,3 +1,5 @@
+use std::sync::Arc;
+
 use serde::{Deserialize, Serialize};
 
 use super::{Coord, Direction};
@@ -17,11 +19,11 @@ pub struct Request {
 #[derive(Debug, PartialEq, Eq, Clone, Deserialize)]
 pub struct Game {
     /// A unique identifier for this Game.
-    pub id: String,
+    pub id: Arc<str>,
     /// Information about the ruleset being used to run this Game.
     pub ruleset: Ruleset,
     /// The name of the map being played on.
-    pub map: String,
+    pub map: Arc<str>,
     /// How much time your snake has to respond to requests for this Game.
     pub timeout: u16,
     /// The source of this Game.
@@ -31,15 +33,15 @@ pub struct Game {
     /// - arena
     /// - challenge
     /// - custom
-    pub source: String,
+    pub source: Arc<str>,
 }
 
 #[derive(Debug, PartialEq, Eq, Clone, Deserialize)]
 pub struct Ruleset {
     /// Name of the ruleset being used to run this game.
-    pub name: String,
+    pub name: Arc<str>,
     /// The release version of the Rules module used in this game.
-    pub version: String,
+    pub version: Arc<str>,
     /// A collection of specific settings being used by the current game that control how the rules
     /// are applied.
     pub settings: Settings,
@@ -84,9 +86,9 @@ pub struct Board {
 #[derive(Debug, PartialEq, Eq, Clone, Deserialize)]
 pub struct Battlesnake {
     /// Unique identifier for this Battlesnake in the context of the current Game.
-    pub id: String,
+    pub id: Arc<str>,
     /// Name given to this Battlesnake by its author
-    pub name: String,
+    pub name: Arc<str>,
     /// Health value of this Battlesnake, between 0 and 100
     pub health: u8,
     /// Array of coordinates representing the Battlesnake's location on the game board.
@@ -94,7 +96,7 @@ pub struct Battlesnake {
     pub body: Vec<Coord>,
     /// The previous response time of this Battlesnake, in milliseconds.
     /// If the Battlesnake timed out and failed to respond, the game timeout will be returned
-    pub latency: String,
+    pub latency: Arc<str>,
     /// Coordinates for this Battlesnake's head.
     /// Equivalent to the first element of the body array.
     pub head: Coord,
@@ -102,10 +104,10 @@ pub struct Battlesnake {
     /// Equivalent to the length of the body array.
     pub length: u16,
     /// Message shouted by this Battlesnake on the previous turn
-    pub shout: String,
+    pub shout: Option<Arc<str>>,
     /// The squad that the Battlesnake belongs to.
     /// Used to identify squad members in Squad Mode games.
-    pub squad: String,
+    pub squad: Arc<str>,
 }
 
 #[derive(Debug, PartialEq, Eq, Clone, Serialize)]