diff --git a/Cargo.lock b/Cargo.lock
index bd5cbe4..6d4ab83 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -224,6 +224,7 @@ dependencies = [
  "async-trait",
  "axum-core 0.4.1",
  "axum-macros",
+ "base64",
  "bytes",
  "futures-util",
  "http 1.0.0",
@@ -243,8 +244,10 @@ dependencies = [
  "serde_json",
  "serde_path_to_error",
  "serde_urlencoded",
+ "sha1",
  "sync_wrapper",
  "tokio",
+ "tokio-tungstenite",
  "tower",
  "tower-layer",
  "tower-service",
@@ -430,6 +433,7 @@ dependencies = [
  "axum-extra",
  "base64",
  "chrono",
+ "futures",
  "image",
  "regex",
  "reqwest",
@@ -660,6 +664,12 @@ dependencies = [
  "typenum",
 ]
 
+[[package]]
+name = "data-encoding"
+version = "2.5.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7e962a19be5cfc3f3bf6dd8f61eb50107f356ad6270fbb3ed41476571db78be5"
+
 [[package]]
 name = "der"
 version = "0.7.8"
@@ -843,6 +853,21 @@ dependencies = [
  "percent-encoding",
 ]
 
+[[package]]
+name = "futures"
+version = "0.3.29"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "da0290714b38af9b4a7b094b8a37086d1b4e61f2df9122c3cad2577669145335"
+dependencies = [
+ "futures-channel",
+ "futures-core",
+ "futures-executor",
+ "futures-io",
+ "futures-sink",
+ "futures-task",
+ "futures-util",
+]
+
 [[package]]
 name = "futures-channel"
 version = "0.3.29"
@@ -916,6 +941,7 @@ version = "0.3.29"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "a19526d624e703a3179b3d322efec918b6246ea0fa51d41124525f00f1cc8104"
 dependencies = [
+ "futures-channel",
  "futures-core",
  "futures-io",
  "futures-macro",
@@ -3301,6 +3327,18 @@ dependencies = [
  "tokio",
 ]
 
+[[package]]
+name = "tokio-tungstenite"
+version = "0.20.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "212d5dcb2a1ce06d81107c3d0ffa3121fe974b73f068c8282cb1c32328113b6c"
+dependencies = [
+ "futures-util",
+ "log",
+ "tokio",
+ "tungstenite",
+]
+
 [[package]]
 name = "tokio-util"
 version = "0.7.10"
@@ -3554,6 +3592,25 @@ dependencies = [
  "linked-hash-map",
 ]
 
+[[package]]
+name = "tungstenite"
+version = "0.20.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9e3dac10fd62eaf6617d3a904ae222845979aec67c615d1c842b4002c7666fb9"
+dependencies = [
+ "byteorder",
+ "bytes",
+ "data-encoding",
+ "http 0.2.11",
+ "httparse",
+ "log",
+ "rand",
+ "sha1",
+ "thiserror",
+ "url",
+ "utf-8",
+]
+
 [[package]]
 name = "typenum"
 version = "1.17.0"
@@ -3643,6 +3700,12 @@ version = "2.1.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "daf8dba3b7eb870caf1ddeed7bc9d2a049f3cfdfae7cb521b087cc33ae4c49da"
 
+[[package]]
+name = "utf-8"
+version = "0.7.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "09cc8ee72d2a9becf2f2febe0205bbed8fc6615b7cb429ad062dc7b7ddd036a9"
+
 [[package]]
 name = "uuid"
 version = "1.6.1"
diff --git a/Cargo.toml b/Cargo.toml
index 22c718f..1be3adb 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -6,10 +6,11 @@ edition = "2021"
 [dependencies]
 askama = { version = "0.12.1", features = ["with-axum"] }
 askama_axum = "0.4.0"
-axum = { version = "0.7.2", features = ["macros", "multipart"] }
+axum = { version = "0.7.2", features = ["macros", "multipart", "ws"] }
 axum-extra = { version = "0.9.0", features = ["typed-header"] }
 base64 = "0.21.5"
 chrono = { version = "0.4.31", default-features = false, features = ["std"] }
+futures = "0.3.29"
 image = "0.24.7"
 regex = "1.10.2"
 reqwest = { version = "0.11.22", features = ["json"] }
diff --git a/src/cal/day19.rs b/src/cal/day19.rs
new file mode 100644
index 0000000..05a3489
--- /dev/null
+++ b/src/cal/day19.rs
@@ -0,0 +1,128 @@
+use axum::{
+    extract::{
+        ws::{WebSocket, WebSocketUpgrade},
+        Path, State,
+    },
+    response::IntoResponse,
+    routing::{get, post},
+    Router,
+};
+use futures::{SinkExt, StreamExt};
+use std::{
+    collections::HashMap,
+    sync::{
+        atomic::{AtomicU64, Ordering},
+        Arc, Mutex,
+    },
+};
+use tokio::{spawn, sync::broadcast::Sender};
+
+#[derive(Clone, serde::Serialize)]
+struct Message {
+    user: String,
+    message: String,
+}
+
+#[derive(Clone)]
+struct Day19State {
+    view_count: Arc<AtomicU64>,
+    sockets: Arc<Mutex<HashMap<u64, Sender<Message>>>>,
+}
+
+pub(crate) fn router() -> Router {
+    Router::new()
+        .route("/19/ws/ping", get(ping_handler))
+        .route("/19/reset", post(reset))
+        .route("/19/views", get(views))
+        .route("/19/ws/room/:id/user/:user", get(room_handler))
+        .with_state(Day19State {
+            view_count: Arc::new(AtomicU64::new(0)),
+            sockets: Arc::new(Mutex::new(HashMap::new())),
+        })
+}
+
+async fn ping_handler(ws: WebSocketUpgrade) -> impl IntoResponse {
+    ws.on_upgrade(ping)
+}
+
+async fn ping(mut ws: WebSocket) {
+    let mut served = false;
+    while let Some(Ok(msg)) = ws.recv().await {
+        if let Ok(msg) = msg.to_text() {
+            match msg {
+                "serve" => served = true,
+                "ping" if served => {
+                    let _ = ws.send("pong".into()).await;
+                }
+                _ => {}
+            }
+        }
+    }
+}
+
+async fn reset(State(state): State<Day19State>) {
+    state.view_count.store(0, Ordering::Relaxed);
+}
+
+async fn views(State(state): State<Day19State>) -> impl IntoResponse {
+    state.view_count.load(Ordering::Relaxed).to_string()
+}
+
+async fn room_handler(
+    ws: WebSocketUpgrade,
+    Path((id, user)): Path<(u64, String)>,
+    State(state): State<Day19State>,
+) -> impl IntoResponse {
+    ws.on_upgrade(move |s| room(s, id, user, state))
+}
+
+#[derive(serde::Deserialize)]
+struct WsMsg {
+    message: String,
+}
+
+async fn room(ws: WebSocket, id: u64, user: String, state: Day19State) {
+    let send = {
+        let Ok(mut map) = state.sockets.lock() else {
+            return;
+        };
+
+        if let Some(ch) = map.get(&id) {
+            ch.clone()
+        } else {
+            let ch = Sender::new(128);
+            map.insert(id, ch.clone());
+            ch
+        }
+    };
+
+    let (mut ws_send, mut ws_recv) = ws.split();
+
+    let mut recv = send.subscribe();
+    let recv_task = spawn(async move {
+        while let Ok(message) = recv.recv().await {
+            if let Ok(message) = serde_json::to_string(&message) {
+                if ws_send.send(message.into()).await.is_ok() {
+                    state.view_count.fetch_add(1, Ordering::Relaxed);
+                } else {
+                    return;
+                }
+            }
+        }
+    });
+
+    while let Some(Ok(msg)) = ws_recv.next().await {
+        if let Ok(msg) = msg.into_text() {
+            if let Ok(WsMsg { message }) = serde_json::from_str::<WsMsg>(&msg) {
+                if message.len() <= 128 {
+                    let _ = send.send(Message {
+                        user: user.clone(),
+                        message,
+                    });
+                }
+            }
+        }
+    }
+
+    recv_task.abort();
+}
diff --git a/src/cal/mod.rs b/src/cal/mod.rs
index 7cddaf9..f544ec4 100644
--- a/src/cal/mod.rs
+++ b/src/cal/mod.rs
@@ -10,6 +10,7 @@ mod day13;
 mod day14;
 mod day15;
 mod day18;
+mod day19;
 
 pub(crate) fn router(pool: sqlx::PgPool) -> axum::Router {
     axum::Router::new()
@@ -25,4 +26,5 @@ pub(crate) fn router(pool: sqlx::PgPool) -> axum::Router {
         .nest("/", day14::router())
         .nest("/", day15::router())
         .nest("/", day18::router(pool))
+        .nest("/", day19::router())
 }