diff --git a/Cargo.lock b/Cargo.lock
index 63e1fd5..d653a94 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -573,9 +573,9 @@ checksum = "5443807d6dff69373d433ab9ef5378ad8df50ca6298caf15de6e52e24aaf54d5"
 
 [[package]]
 name = "errno"
-version = "0.3.5"
+version = "0.3.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ac3e13f66a2f95e32a39eaa81f6b95d42878ca0e1db0c7543723dfe12557e860"
+checksum = "7c18ee0ed65a5f1f81cac6b1d213b69c35fa47d4252ad41f1486dbd8226fe36e"
 dependencies = [
  "libc",
  "windows-sys",
@@ -593,9 +593,9 @@ dependencies = [
 
 [[package]]
 name = "fiat-crypto"
-version = "0.2.2"
+version = "0.2.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a481586acf778f1b1455424c343f71124b048ffa5f4fc3f8f6ae9dc432dcb3c7"
+checksum = "f69037fe1b785e84986b4f2cbcf647381876a00671d25ceef715d7812dd7e1dd"
 
 [[package]]
 name = "filetime"
@@ -713,9 +713,9 @@ dependencies = [
 
 [[package]]
 name = "getrandom"
-version = "0.2.10"
+version = "0.2.11"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "be4136b2a15dd319360be1c07d9933517ccf0be8f16bf62a3bee4f0d618df427"
+checksum = "fe9006bed769170c11f845cf00c7c1e9092aeb3f268e007c3e760ac68008070f"
 dependencies = [
  "cfg-if",
  "js-sys",
@@ -1028,9 +1028,9 @@ dependencies = [
 
 [[package]]
 name = "libc"
-version = "0.2.149"
+version = "0.2.150"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a08173bc88b7955d1b3145aa561539096c421ac8debde8cbc3612ec635fee29b"
+checksum = "89d92a4743f9a61002fae18374ed11e7973f530cb3a3255fb354818118b2203c"
 
 [[package]]
 name = "libm"
@@ -1040,9 +1040,9 @@ checksum = "4ec2a862134d2a7d32d7983ddcdd1c4923530833c9f2ea1a44fc5fa473989058"
 
 [[package]]
 name = "linux-raw-sys"
-version = "0.4.10"
+version = "0.4.11"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "da2479e8c062e40bf0066ffa0bc823de0a9368974af99c9f6df941d2c231e03f"
+checksum = "969488b55f8ac402214f3f5fd243ebb7206cf82de60d3172994707a4bcc2b829"
 
 [[package]]
 name = "lock_api"
@@ -1668,9 +1668,9 @@ dependencies = [
 
 [[package]]
 name = "rustls-pemfile"
-version = "1.0.3"
+version = "1.0.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2d3987094b1d07b653b7dfdc3f70ce9a1da9c51ac18c1b06b662e4f9a0e9f4b2"
+checksum = "1c74cae0a4cf6ccbbf5f359f08efdf8ee7e1dc532573bf0db71968cb56b1448c"
 dependencies = [
  "base64 0.21.5",
 ]
@@ -1773,9 +1773,9 @@ checksum = "836fa6a3e1e547f9a2c4040802ec865b5d85f4014efe00555d7090a3dcaa1090"
 
 [[package]]
 name = "serde"
-version = "1.0.190"
+version = "1.0.192"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "91d3c334ca1ee894a2c6f6ad698fe8c435b76d504b13d436f0685d648d6d96f7"
+checksum = "bca2a08484b285dcb282d0f67b26cadc0df8b19f8c12502c13d966bf9482f001"
 dependencies = [
  "serde_derive",
 ]
@@ -1792,9 +1792,9 @@ dependencies = [
 
 [[package]]
 name = "serde_derive"
-version = "1.0.190"
+version = "1.0.192"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "67c5609f394e5c2bd7fc51efda478004ea80ef42fee983d5c67a65e34f32c0e3"
+checksum = "d6c7207fbec9faa48073f3e3074cbe553af6ea512d7c21ba46e434e70ea9fbc1"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -1922,9 +1922,9 @@ dependencies = [
 
 [[package]]
 name = "smallvec"
-version = "1.11.1"
+version = "1.11.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "942b4a808e05215192e39f4ab80813e599068285906cc91aa64f923db842bd5a"
+checksum = "4dccd0940a2dcdf68d092b8cbab7dc0ad8fa938bf95787e1b916b0e3d0e8e970"
 
 [[package]]
 name = "socket2"
@@ -1982,9 +1982,9 @@ checksum = "81cdd64d312baedb58e21336b31bc043b77e01cc99033ce76ef539f78e965ebc"
 
 [[package]]
 name = "syn"
-version = "2.0.38"
+version = "2.0.39"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e96b79aaa137db8f61e26363a0c9b47d8b4ec75da28b7d1d614c2303e232408b"
+checksum = "23e78b90f2fcf45d3e842032ce32e3f2d1545ba6636271dcbf24fa306d87be7a"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -2093,9 +2093,9 @@ checksum = "1f3ccbac311fea05f86f61904b462b55fb3df8837a366dfc601a0161d0532f20"
 
 [[package]]
 name = "tokio"
-version = "1.33.0"
+version = "1.34.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4f38200e3ef7995e5ef13baec2f432a6da0aa9ac495b2c0e8f3b7eec2c92d653"
+checksum = "d0c014766411e834f7af5b8f4cf46257aab4036ca95e9d2c144a10f59ad6f5b9"
 dependencies = [
  "backtrace",
  "bytes",
@@ -2112,9 +2112,9 @@ dependencies = [
 
 [[package]]
 name = "tokio-macros"
-version = "2.1.0"
+version = "2.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "630bdcf245f78637c13ec01ffae6187cca34625e8c63150d424b59e55af2675e"
+checksum = "5b8a1e28f2deaa14e508979454cb3a223b10b938b45af148bc0986de36f1923b"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -2147,9 +2147,9 @@ dependencies = [
 
 [[package]]
 name = "toml"
-version = "0.8.6"
+version = "0.8.8"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8ff9e3abce27ee2c9a37f9ad37238c1bdd4e789c84ba37df76aa4d528f5072cc"
+checksum = "a1a195ec8c9da26928f773888e0742ca3ca1040c6cd859c919c9f59c1954ab35"
 dependencies = [
  "serde",
  "serde_spanned",
@@ -2168,9 +2168,9 @@ dependencies = [
 
 [[package]]
 name = "toml_edit"
-version = "0.20.7"
+version = "0.21.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "70f427fce4d84c72b5b732388bf4a9f4531b53f74e2887e3ecb2481f68f66d81"
+checksum = "d34d383cd00a163b4a5b85053df514d45bc330f6de7737edfe0a93311d1eaa03"
 dependencies = [
  "indexmap 2.1.0",
  "serde",
diff --git a/src/error.rs b/src/error.rs
index 85a879e..7618f9e 100644
--- a/src/error.rs
+++ b/src/error.rs
@@ -5,6 +5,7 @@ use axum::{
 };
 use log::error;
 use thiserror::Error;
+use tokio::task::JoinError;
 
 #[derive(Debug, Error)]
 pub enum Error {
@@ -49,6 +50,9 @@ pub enum Error {
 
     #[error("Prometheus: {0:?}")]
     Prometheus(std::fmt::Error),
+
+    #[error("join error")]
+    Join(#[from] JoinError),
 }
 
 impl IntoResponse for Error {
diff --git a/src/main.rs b/src/main.rs
index d08b75b..edbc119 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -28,13 +28,13 @@ use garbage_collector::{start_gc, GarbageCollectorItem};
 use prometheus_client::{
     encoding::EncodeLabelSet,
     metrics::{counter::Counter, family::Family, gauge::Gauge},
-    registry::Registry,
+    registry::{self, Registry},
 };
 use question::{single_choice::SingleChoiceQuestion, Question};
 use sailfish::TemplateOnce;
 use serde::{Deserialize, Serialize};
 use stream::{PlayerBroadcastStream, ViewerBroadcastStream};
-use tokio::sync::RwLock;
+use tokio::{sync::RwLock, task::spawn_blocking};
 use tower::ServiceBuilder;
 use tower_http::services::ServeDir;
 use tower_sessions::{cookie::SameSite, MemoryStore, SessionManagerLayer};
@@ -313,9 +313,14 @@ pub async fn sse_player(
 }
 
 async fn metrics(State(app_state): State<AppState>) -> HandlerResult<impl IntoResponse> {
-    let mut buffer = String::new();
-    prometheus_client::encoding::text::encode(&mut buffer, &app_state.prometheus_registry)
-        .map_err(Error::Prometheus)?;
+    let registry = app_state.prometheus_registry.clone();
+    let buffer = spawn_blocking::<_, Result<String, Error>>(move || {
+        let mut buffer = String::new();
+        prometheus_client::encoding::text::encode(&mut buffer, &registry)
+            .map_err(Error::Prometheus)?;
+        Ok(buffer)
+    })
+    .await??;
 
     let mut headers = HeaderMap::new();
     headers.insert(