diff --git a/.drone.yml b/.drone.yml
index c20a29e..2e2d263 100644
--- a/.drone.yml
+++ b/.drone.yml
@@ -4,26 +4,21 @@ name: default
 
 steps:
   - name: build
-    image: rust:1.68
+    image: rust:1.77
     commands:
       - cargo build
-    volumes:
+    volumes: &caches
       - name: cargo-cache
         path: /cache/cargo
-    environment:
+    environment: &env
       CARGO_HOME: /cache/cargo
-      CARGO_REGISTRIES_CRATES_IO_PROTOCOL: sparse
 
   - name: test
-    image: rust:1.68
+    image: rust:1.77
     commands:
       - cargo test --all-features
-    volumes:
-      - name: cargo-cache
-        path: /cache/cargo
-    environment:
-      CARGO_HOME: /cache/cargo
-      CARGO_REGISTRIES_CRATES_IO_PROTOCOL: sparse
+    volumes: *caches
+    environment: *env
     depends_on:
       - build
 
diff --git a/Cargo.toml b/Cargo.toml
index d660e5d..b23e17b 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -3,6 +3,7 @@ strip = true
 panic = "abort"
 
 [workspace]
+resolver = "2"
 members = [
     "board-shared",
     "board-frontend",
diff --git a/board-frontend/Cargo.toml b/board-frontend/Cargo.toml
index edca37f..6fe961d 100644
--- a/board-frontend/Cargo.toml
+++ b/board-frontend/Cargo.toml
@@ -8,13 +8,13 @@ categories = ["gui", "wasm", "web-programming"]
 
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 [dependencies]
-yew = { version="0.20", features=["csr"] }
+yew = { version = "0.21.0", features=["csr"] }
 board-shared = { path = "../board-shared" }
 board-network = { path = "../board-network" }
-gloo-dialogs = "0.1.1"
+gloo-dialogs = "0.2.0"
 getrandom = { version = "0.2.8", features = ["js"] }
-gloo-net = "0.2.6"
+gloo-net = "0.5.0"
 futures = "0.3.26"
 serde_json = "1.0.93"
-gloo-utils = "0.1.6"
+gloo-utils = "0.2.0"
 web-sys = "0.3.61"
diff --git a/board-frontend/src/hand_view.rs b/board-frontend/src/hand_view.rs
index d071835..a4042f5 100644
--- a/board-frontend/src/hand_view.rs
+++ b/board-frontend/src/hand_view.rs
@@ -1,7 +1,7 @@
 use crate::tile_view::TileView;
 use board_shared::game::Hand;
+use yew::html;
 use yew::prelude::*;
-use yew::{html, Callback, Html};
 
 #[derive(Properties, PartialEq)]
 pub struct HandViewProps {
diff --git a/board-frontend/src/remote_view.rs b/board-frontend/src/remote_view.rs
index ee01749..06ae6a5 100644
--- a/board-frontend/src/remote_view.rs
+++ b/board-frontend/src/remote_view.rs
@@ -43,7 +43,7 @@ pub fn remote_game_view(
     }: &RemoteGameViewProps,
 ) -> Html {
     macro_rules! send_client_message {
-        ($write:expr, $message:expr) => {{
+        ($write:ident, $message:expr) => {{
             let write = $write.clone();
             spawn_local(async move {
                 write
@@ -68,61 +68,54 @@ pub fn remote_game_view(
         let player_name = player_name.clone();
         let room_name = room_name.clone();
         let write = write.clone();
-        use_effect_with_deps(
-            move |_| {
-                send_client_message!(
-                    write,
-                    if let Some(room_name) = room_name {
-                        ClientMessage::JoinRoom(room_name, player_name)
-                    } else {
-                        ClientMessage::CreateRoom(player_name)
-                    }
-                );
-            },
-            (),
-        );
+        use_effect(move || {
+            send_client_message!(
+                write,
+                if let Some(room_name) = room_name {
+                    ClientMessage::JoinRoom(room_name, player_name)
+                } else {
+                    ClientMessage::CreateRoom(player_name)
+                }
+            );
+        });
 
         let is_started = is_started.clone();
         let current_player_turn = current_player_turn.clone();
         let read = read.clone();
-        use_effect_with_deps(
-            move |_| {
-                spawn_local(async move {
-                    while let Some(event) = read.borrow_mut().next().await {
-                        if let Message::Text(msg) = event.unwrap() {
-                            match serde_json::from_str::<ServerMessage>(&msg) {
-                                Ok(ServerMessage::JoinedRoom {
-                                    room_name,
-                                    has_started,
-                                    ..
-                                }) => {
-                                    alert(&format!("Joined room {room_name}"));
-                                    is_started.set(has_started);
-                                }
-                                Ok(ServerMessage::PlayerTurn(player_id)) => {
-                                    current_player_turn.set(player_id);
-                                    is_started.set(true);
-                                }
-                                Ok(ServerMessage::SyncHand(hand)) => {
-                                    in_hand
-                                        .set(Hand::new(hand.iter().map(|&x| x.into()).collect()));
-                                }
-                                Ok(ServerMessage::TilePlaced(pos, tile)) => {
-                                    let mut changed = board.deref().clone();
-                                    changed.set(pos.x, pos.y, tile.into());
-                                    board.set(changed);
-                                }
-                                r => {
-                                    alert(&format!("{r:?}"));
-                                }
-                            };
-                        }
+        use_effect(move || {
+            spawn_local(async move {
+                while let Some(event) = read.borrow_mut().next().await {
+                    if let Message::Text(msg) = event.unwrap() {
+                        match serde_json::from_str::<ServerMessage>(&msg) {
+                            Ok(ServerMessage::JoinedRoom {
+                                room_name,
+                                has_started,
+                                ..
+                            }) => {
+                                alert(&format!("Joined room {room_name}"));
+                                is_started.set(has_started);
+                            }
+                            Ok(ServerMessage::PlayerTurn(player_id)) => {
+                                current_player_turn.set(player_id);
+                                is_started.set(true);
+                            }
+                            Ok(ServerMessage::SyncHand(hand)) => {
+                                in_hand.set(Hand::new(hand.iter().map(|&x| x.into()).collect()));
+                            }
+                            Ok(ServerMessage::TilePlaced(pos, tile)) => {
+                                let mut changed = board.deref().clone();
+                                changed.set(pos.x, pos.y, tile.into());
+                                board.set(changed);
+                            }
+                            r => {
+                                alert(&format!("{r:?}"));
+                            }
+                        };
                     }
-                });
-                || {}
-            },
-            (),
-        );
+                }
+            });
+            || {}
+        });
     }
 
     let on_tile_select = {
diff --git a/board-frontend/src/tile_view.rs b/board-frontend/src/tile_view.rs
index 1992c5e..5e6e9f8 100644
--- a/board-frontend/src/tile_view.rs
+++ b/board-frontend/src/tile_view.rs
@@ -1,6 +1,6 @@
 use board_shared::tile::Tile;
+use yew::html;
 use yew::prelude::*;
-use yew::{html, Callback, Html};
 
 #[derive(Properties, PartialEq)]
 pub struct PlacedTileViewProps {
@@ -54,6 +54,6 @@ pub fn tile_view(
     html! {
         <div class="tile" onclick={Callback::from(move |_| {
             on_select.emit(idx)
-        })}>{ tile }</div>
+        })}>{ tile.to_string() }</div>
     }
 }
diff --git a/board-network/src/lib.rs b/board-network/src/lib.rs
index c087a5c..1b800ec 100644
--- a/board-network/src/lib.rs
+++ b/board-network/src/lib.rs
@@ -1,2 +1 @@
 pub mod protocol;
-pub mod types;
diff --git a/board-network/src/protocol.rs b/board-network/src/protocol.rs
index 4cf239b..5186f67 100644
--- a/board-network/src/protocol.rs
+++ b/board-network/src/protocol.rs
@@ -1,4 +1,6 @@
-use crate::types::{BoardRef, Position2dRef, TileRef};
+use board_shared::board::Board;
+use board_shared::position::Position2d;
+use board_shared::tile::Tile;
 use serde::{Deserialize, Serialize};
 
 /// A message sent by the client to the server.
@@ -19,11 +21,11 @@ pub enum ClientMessage {
     /// Try to place a tile from the hand on the board.
     ///
     /// The server will validate the move and answer with a TilePlaced if the message is valid.
-    TileUse(Position2dRef, usize),
+    TileUse(Position2d, usize),
     /// Try to place an equal sign on the board.
-    TilePlaceEqual(Position2dRef),
+    TilePlaceEqual(Position2d),
     /// Try to remove a tile from the board to add it to the hand.
-    TileTake(Position2dRef),
+    TileTake(Position2d),
     /// Get the server to validate the current player moves.
     Validate,
 }
@@ -35,7 +37,7 @@ pub enum ServerMessage {
     JoinedRoom {
         room_name: String,
         players: Vec<(String, u32, bool)>,
-        board: BoardRef,
+        board: Board,
         active_player: usize,
         has_started: bool,
     },
@@ -50,13 +52,13 @@ pub enum ServerMessage {
     /// Change the current player
     PlayerTurn(usize),
     /// Update the current hand of the player
-    SyncHand(Vec<TileRef>),
+    SyncHand(Vec<Tile>),
     /// Update the score of the n-th player.
     SyncScore(usize, u32),
     /// Informs that a tile has been placed
-    TilePlaced(Position2dRef, TileRef),
+    TilePlaced(Position2d, Tile),
     /// Informs that a tile has been removed
-    TileRemoved(Position2dRef),
+    TileRemoved(Position2d),
     TurnRejected(String),
     /// Notify that the game has ended.
     GameOver,
diff --git a/board-network/src/types.rs b/board-network/src/types.rs
deleted file mode 100644
index 8ca4ffc..0000000
--- a/board-network/src/types.rs
+++ /dev/null
@@ -1,134 +0,0 @@
-use board_shared::{
-    board::Board,
-    position::{Grid2d, Position2d},
-    tile::{Digit, Operator, Tile},
-};
-use serde::{Deserialize, Serialize};
-
-#[derive(Clone, Debug, Serialize, Deserialize)]
-pub struct BoardRef {
-    pub tiles: Vec<Option<TileRef>>,
-    pub width: usize,
-    pub height: usize,
-}
-
-#[derive(Clone, Copy, Debug, Serialize, Deserialize)]
-pub enum TileRef {
-    Digit(DigitRef),
-    Operator(OperatorRef),
-    Equals,
-}
-
-#[derive(Clone, Copy, Debug, Serialize, Deserialize)]
-pub struct DigitRef {
-    pub value: i8,
-    pub has_left_parenthesis: bool,
-    pub has_right_parenthesis: bool,
-}
-
-#[derive(Clone, Copy, Debug, Serialize, Deserialize)]
-pub enum OperatorRef {
-    Add,
-    Subtract,
-    Multiply,
-    Divide,
-}
-
-#[derive(Clone, Copy, Debug, Serialize, Deserialize)]
-pub struct Position2dRef {
-    pub x: usize,
-    pub y: usize,
-}
-
-impl From<&Board> for BoardRef {
-    fn from(value: &Board) -> Self {
-        Self {
-            tiles: value
-                .iter()
-                .map(|tile| tile.map(Into::into))
-                .collect::<Vec<_>>(),
-            width: value.width(),
-            height: value.height(),
-        }
-    }
-}
-
-impl From<Tile> for TileRef {
-    fn from(value: Tile) -> Self {
-        match value {
-            Tile::Digit(digit) => TileRef::Digit(digit.into()),
-            Tile::Operator(operator) => TileRef::Operator(operator.into()),
-            Tile::Equals => TileRef::Equals,
-        }
-    }
-}
-
-impl From<TileRef> for Tile {
-    fn from(value: TileRef) -> Self {
-        match value {
-            TileRef::Digit(digit) => Tile::Digit(digit.into()),
-            TileRef::Operator(operator) => Tile::Operator(operator.into()),
-            TileRef::Equals => Tile::Equals,
-        }
-    }
-}
-
-impl From<Digit> for DigitRef {
-    fn from(value: Digit) -> Self {
-        Self {
-            value: value.value,
-            has_left_parenthesis: value.has_left_parenthesis,
-            has_right_parenthesis: value.has_right_parenthesis,
-        }
-    }
-}
-
-impl From<DigitRef> for Digit {
-    fn from(value: DigitRef) -> Self {
-        Self {
-            value: value.value,
-            has_left_parenthesis: value.has_left_parenthesis,
-            has_right_parenthesis: value.has_right_parenthesis,
-        }
-    }
-}
-
-impl From<Operator> for OperatorRef {
-    fn from(value: Operator) -> Self {
-        match value {
-            Operator::Add => OperatorRef::Add,
-            Operator::Subtract => OperatorRef::Subtract,
-            Operator::Multiply => OperatorRef::Multiply,
-            Operator::Divide => OperatorRef::Divide,
-        }
-    }
-}
-
-impl From<OperatorRef> for Operator {
-    fn from(value: OperatorRef) -> Self {
-        match value {
-            OperatorRef::Add => Operator::Add,
-            OperatorRef::Subtract => Operator::Subtract,
-            OperatorRef::Multiply => Operator::Multiply,
-            OperatorRef::Divide => Operator::Divide,
-        }
-    }
-}
-
-impl From<Position2d> for Position2dRef {
-    fn from(value: Position2d) -> Self {
-        Self {
-            x: value.x,
-            y: value.y,
-        }
-    }
-}
-
-impl From<Position2dRef> for Position2d {
-    fn from(value: Position2dRef) -> Self {
-        Self {
-            x: value.x,
-            y: value.y,
-        }
-    }
-}
diff --git a/board-server/Cargo.toml b/board-server/Cargo.toml
index f14cc12..11c55d8 100644
--- a/board-server/Cargo.toml
+++ b/board-server/Cargo.toml
@@ -7,13 +7,13 @@ edition = "2021"
 
 [dependencies]
 futures = { version = "0.3" }
-board-shared = { path = "../board-shared" }
+board-shared = { path = "../board-shared", features = ["serde"] }
 board-network = { path = "../board-network" }
-smol = "1.3.0"
-async-tungstenite = "0.20.0"
-tungstenite = "0.18.0"
+smol = "2.0.0"
+async-tungstenite = "0.25.0"
+tungstenite = "0.21.0"
 anyhow = "1.0.69"
 rand = "0.8.5"
 serde_json = "1.0.93"
-redis = { version = "0.22.3", features = ["aio", "async-std-comp"] }
+redis = { version = "0.25.2", features = ["aio", "async-std-comp"] }
 async-trait = "0.1.66"
diff --git a/board-server/Dockerfile b/board-server/Dockerfile
index 7b8bc11..4044bf7 100644
--- a/board-server/Dockerfile
+++ b/board-server/Dockerfile
@@ -1,6 +1,5 @@
-FROM rust:1.68.0-slim as builder
+FROM rust:1.77.0-slim as builder
 
-ENV CARGO_REGISTRIES_CRATES_IO_PROTOCOL=sparse
 WORKDIR /usr/src/board
 
 # Build with musl to statically link
diff --git a/board-server/src/leaderboard.rs b/board-server/src/leaderboard.rs
index 21814e8..7621568 100644
--- a/board-server/src/leaderboard.rs
+++ b/board-server/src/leaderboard.rs
@@ -29,13 +29,13 @@ impl RedisLeaderboard {
 #[async_trait]
 impl Leaderboard for RedisLeaderboard {
     async fn add_score(&self, player_name: &str, score: u32) -> Result<(), RedisError> {
-        let mut con = self.client.get_async_connection().await?;
+        let mut con = self.client.get_multiplexed_async_connection().await?;
         con.zadd(LEADERBOARD, player_name, score).await?;
         Ok(())
     }
 
     async fn get_highscores(&self) -> Result<Vec<LeaderboardEntry>, RedisError> {
-        let mut con = self.client.get_async_connection().await?;
+        let mut con = self.client.get_multiplexed_async_connection().await?;
         let count: isize = con.zcard(LEADERBOARD).await?;
         let leaderboard: Vec<LeaderboardEntry> = con
             .zrange_withscores(LEADERBOARD, 0, (count - 1).min(LEADERBOARD_SIZE))
diff --git a/board-server/src/room.rs b/board-server/src/room.rs
index f368df2..383d924 100644
--- a/board-server/src/room.rs
+++ b/board-server/src/room.rs
@@ -1,7 +1,6 @@
 use crate::leaderboard::{InMemoryLeaderboard, Leaderboard};
 use crate::player::Player;
 use board_network::protocol::{ClientMessage, ServerMessage};
-use board_network::types::TileRef;
 use board_shared::board::Board;
 use board_shared::deck::RngDeck;
 use board_shared::expr::is_valid_guess;
@@ -87,7 +86,7 @@ impl Room {
                 .iter()
                 .map(|p| (p.name.clone(), p.score, p.ws.is_some()))
                 .collect(),
-            board: (&self.board).into(),
+            board: self.board.clone(),
             active_player: self.active_player,
             has_started: self.has_started,
         })?;
@@ -328,13 +327,7 @@ impl Room {
     fn sync_hand(&mut self, player_id: usize) {
         self.send(
             player_id,
-            ServerMessage::SyncHand(
-                self.players[player_id]
-                    .hand
-                    .iter()
-                    .map(|t| <Tile as Into<TileRef>>::into(*t))
-                    .collect::<Vec<_>>(),
-            ),
+            ServerMessage::SyncHand(self.players[player_id].hand.tiles.clone()),
         );
     }
 }
diff --git a/board-shared/Cargo.toml b/board-shared/Cargo.toml
index 2a3721d..5657e3b 100644
--- a/board-shared/Cargo.toml
+++ b/board-shared/Cargo.toml
@@ -7,8 +7,10 @@ edition = "2021"
 
 [dependencies]
 enum-map = "2.4.2"
-itertools = { version = "0.10.5", optional = true }
+itertools = { version = "0.12.1", optional = true }
 rand = "0.8.5"
+serde = { version = "1.0.197", features = ["derive"], optional = true }
 
 [features]
-ai = ["itertools"]
+ai = ["dep:itertools"]
+serde = ["dep:serde"]
diff --git a/board-shared/src/board.rs b/board-shared/src/board.rs
index f2d980a..cb9d723 100644
--- a/board-shared/src/board.rs
+++ b/board-shared/src/board.rs
@@ -12,6 +12,7 @@ const DEFAULT_BOARD_SIZE: usize = 19;
 /// to create a new board with a default size. To create a board with a custom
 /// size, use [`Board::new()`].
 #[derive(Debug, Clone, PartialEq, Eq)]
+#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
 pub struct Board {
     tiles: Vec<Option<Tile>>,
     width: usize,
@@ -192,7 +193,7 @@ impl Board {
     }
 
     /// Tests whether the given positions are part of the same chain.
-    fn belong_to_same_chain(&self, positions: &Vec<Position2d>, direction: Direction) -> bool {
+    fn belong_to_same_chain(&self, positions: &[Position2d], direction: Direction) -> bool {
         let mut it = positions.iter().copied().peekable();
         while let Some(mut pos) = it.next() {
             if let Some(&next) = it.peek() {
diff --git a/board-shared/src/game.rs b/board-shared/src/game.rs
index 40504d1..7528935 100644
--- a/board-shared/src/game.rs
+++ b/board-shared/src/game.rs
@@ -54,11 +54,7 @@ impl Hand {
     }
 
     pub fn remove(&mut self, idx: usize) -> Option<Tile> {
-        if idx < self.tiles.len() {
-            Some(self.tiles.remove(idx))
-        } else {
-            None
-        }
+        (idx < self.tiles.len()).then(|| self.tiles.remove(idx))
     }
 
     pub fn iter(&self) -> impl Iterator<Item = &Tile> {
diff --git a/board-shared/src/lexer.rs b/board-shared/src/lexer.rs
index 777cc1d..f0a2ed1 100644
--- a/board-shared/src/lexer.rs
+++ b/board-shared/src/lexer.rs
@@ -83,7 +83,7 @@ mod tests {
 
     #[test]
     fn test_lex() {
-        let input = vec![
+        let input = [
             Tile::Digit(Digit::new(1)),
             Tile::Digit(Digit::new(2)),
             Tile::Digit(Digit::new(3)),
@@ -104,7 +104,7 @@ mod tests {
 
     #[test]
     fn test_lex_parentheses() {
-        let input = vec![
+        let input = [
             Tile::Digit(Digit::new(1)),
             Tile::Operator(Operator::Subtract),
             Tile::Digit(Digit {
@@ -133,7 +133,7 @@ mod tests {
 
     #[test]
     fn test_lex_parentheses_long() {
-        let input = vec![
+        let input = [
             Tile::Digit(Digit {
                 value: 1,
                 has_left_parenthesis: true,
diff --git a/board-shared/src/lib.rs b/board-shared/src/lib.rs
index 7ca103b..4146849 100644
--- a/board-shared/src/lib.rs
+++ b/board-shared/src/lib.rs
@@ -1,15 +1,15 @@
-///! # Scrabble with Numbers
-///!
-///! This crate provides the core game logic for the Scrabble with Numbers game.
-///! It can be used standalone, or as a library for other projects.
-///!
-///! ## Features
-///! - Create and verify game expressions, such as `2*3+4*5`.
-///! - Generate valid automatic moves for a given board state, with the `ai` feature.
-///! - Check if a player move valid.
-///! - Calculate the score of an expression.
-///!
-///! If you are looking for a server implementation, see the `board-server` crate.
+//! # Scrabble with Numbers
+//!
+//! This crate provides the core game logic for the Scrabble with Numbers game.
+//! It can be used standalone, or as a library for other projects.
+//!
+//! ## Features
+//! - Create and verify game expressions, such as `2*3+4*5`.
+//! - Generate valid automatic moves for a given board state, with the `ai` feature.
+//! - Check if a player move valid.
+//! - Calculate the score of an expression.
+//!
+//! If you are looking for a server implementation, see the `board-server` crate.
 
 #[cfg(feature = "ai")]
 pub mod ai;
diff --git a/board-shared/src/parser.rs b/board-shared/src/parser.rs
index 9c75f77..aee4915 100644
--- a/board-shared/src/parser.rs
+++ b/board-shared/src/parser.rs
@@ -39,20 +39,17 @@ pub fn parse(tokens: &[Token]) -> Result<Expressions, ()> {
 fn parse_primary<'a>(
     tokens: &mut Peekable<impl Iterator<Item = &'a Token>>,
 ) -> Result<Expression, ()> {
-    if let Some(Token::NumberLiteral(value)) = tokens.peek() {
-        tokens.next();
-        Ok(Expression::Digit(*value))
-    } else if let Some(Token::LeftParen) = tokens.peek() {
-        tokens.next();
-        let expr = parse_term(tokens)?;
-        if let Some(Token::RightParen) = tokens.peek() {
-            tokens.next();
-            Ok(Expression::Parentheses(Box::new(expr)))
-        } else {
-            Err(())
+    match tokens.next() {
+        Some(Token::NumberLiteral(value)) => Ok(Expression::Digit(*value)),
+        Some(Token::LeftParen) => {
+            let expr = parse_term(tokens)?;
+            if let Some(Token::RightParen) = tokens.next() {
+                Ok(Expression::Parentheses(Box::new(expr)))
+            } else {
+                Err(())
+            }
         }
-    } else {
-        Err(())
+        _ => Err(()),
     }
 }
 
@@ -104,7 +101,7 @@ mod tests {
 
     #[test]
     fn test_parse() {
-        let tokens = vec![
+        let tokens = [
             Token::NumberLiteral(1),
             Token::Operator(Operator::Add),
             Token::NumberLiteral(2),
@@ -128,7 +125,7 @@ mod tests {
 
     #[test]
     fn test_parse_reverse() {
-        let tokens = vec![
+        let tokens = [
             Token::NumberLiteral(2),
             Token::Operator(Operator::Multiply),
             Token::NumberLiteral(3),
@@ -152,7 +149,7 @@ mod tests {
 
     #[test]
     fn test_parse_parentheses() {
-        let tokens = vec![
+        let tokens = [
             Token::LeftParen,
             Token::NumberLiteral(1),
             Token::Operator(Operator::Add),
@@ -178,7 +175,7 @@ mod tests {
 
     #[test]
     fn test_parse_equals() {
-        let tokens = vec![
+        let tokens = [
             Token::NumberLiteral(1),
             Token::Equals,
             Token::NumberLiteral(2),
@@ -198,7 +195,7 @@ mod tests {
 
     #[test]
     fn test_parse_unary_and_binary_minus() {
-        let tokens = vec![
+        let tokens = [
             Token::Operator(Operator::Subtract),
             Token::NumberLiteral(1),
             Token::Operator(Operator::Subtract),
@@ -220,7 +217,7 @@ mod tests {
 
     #[test]
     fn test_parse_unary_before_parenthesis() {
-        let tokens = vec![
+        let tokens = [
             Token::Operator(Operator::Subtract),
             Token::LeftParen,
             Token::NumberLiteral(9),
@@ -244,7 +241,7 @@ mod tests {
 
     #[test]
     fn test_double_unary() {
-        let tokens = vec![
+        let tokens = [
             Token::Operator(Operator::Subtract),
             Token::Operator(Operator::Subtract),
             Token::NumberLiteral(7),
diff --git a/board-shared/src/position.rs b/board-shared/src/position.rs
index 8aa53ea..c591d0e 100644
--- a/board-shared/src/position.rs
+++ b/board-shared/src/position.rs
@@ -1,5 +1,6 @@
 /// A position in a 2d grid.
 #[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
+#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
 pub struct Position2d {
     pub x: usize,
     pub y: usize,
diff --git a/board-shared/src/score.rs b/board-shared/src/score.rs
index 9a4313b..98ef569 100644
--- a/board-shared/src/score.rs
+++ b/board-shared/src/score.rs
@@ -14,14 +14,10 @@ fn calc_expression_score(tiles: &[Tile]) -> u32 {
     for token in tiles {
         match token {
             Tile::Digit(_) => digit_score += 1,
-            Tile::Operator(op) => {
-                match op {
-                    Operator::Add | Operator::Subtract => multiplier = 2,
-                    Operator::Multiply => multiplier = 3,
-                    Operator::Divide => digit_score += 10,
-                };
-            }
-            _ => unreachable!(),
+            Tile::Operator(Operator::Add | Operator::Subtract) => multiplier = 2,
+            Tile::Operator(Operator::Multiply) => multiplier = 3,
+            Tile::Operator(Operator::Divide) => digit_score += 10,
+            Tile::Equals => unreachable!(),
         }
     }
     digit_score * multiplier
diff --git a/board-shared/src/tile.rs b/board-shared/src/tile.rs
index 8f88bb1..7e5f612 100644
--- a/board-shared/src/tile.rs
+++ b/board-shared/src/tile.rs
@@ -1,8 +1,10 @@
 use enum_map::Enum;
 use std::fmt;
+use std::str::FromStr;
 
 /// A single digit that can be wrapped in parentheses.
 #[derive(Debug, PartialEq, Eq, Copy, Clone)]
+#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
 pub struct Digit {
     pub value: i8,
     pub has_left_parenthesis: bool,
@@ -61,6 +63,7 @@ impl TryFrom<&str> for Digit {
 
 /// An operator that can be applied between two terms.
 #[derive(Debug, PartialEq, Eq, Copy, Clone, Enum)]
+#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
 pub enum Operator {
     Add,
     Subtract,
@@ -104,6 +107,7 @@ impl TryFrom<char> for Operator {
 
 /// A single piece of a mathematical expression.
 #[derive(Debug, PartialEq, Eq, Copy, Clone)]
+#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
 pub enum Tile {
     Digit(Digit),
     Operator(Operator),
@@ -114,6 +118,14 @@ impl TryFrom<&str> for Tile {
     type Error = ();
 
     fn try_from(value: &str) -> Result<Self, Self::Error> {
+        Self::from_str(value)
+    }
+}
+
+impl FromStr for Tile {
+    type Err = ();
+
+    fn from_str(value: &str) -> Result<Self, Self::Err> {
         if let Ok(digit) = Digit::try_from(value) {
             return Ok(Tile::Digit(digit));
         }