diff --git a/Cargo.lock b/Cargo.lock
index 76593e3..7066a83 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -32,6 +32,18 @@ version = "1.0.83"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "25bdb32cbbdce2b519a9cd7df3a678443100e265d5e25ca763b7572a5104f5f3"
 
+[[package]]
+name = "arrayref"
+version = "0.3.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6b4930d2cb77ce62f89ee5d5289b4ac049559b1c45539271f5ed4fdc7db34545"
+
+[[package]]
+name = "arrayvec"
+version = "0.7.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "96d30a06541fbafbc7f82ed10c06164cfbd2c401138f6addd8404629c4b16711"
+
 [[package]]
 name = "async-stream"
 version = "0.3.5"
@@ -149,6 +161,19 @@ version = "2.5.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "cf4b9d6a944f767f8e5e0db018570623c85f3d925ac718db4e06d0187adb21c1"
 
+[[package]]
+name = "blake3"
+version = "1.5.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "30cca6d3674597c30ddf2c587bf8d9d65c9a84d2326d941cc79c9842dfe0ef52"
+dependencies = [
+ "arrayref",
+ "arrayvec",
+ "cc",
+ "cfg-if",
+ "constant_time_eq",
+]
+
 [[package]]
 name = "byteorder"
 version = "1.5.0"
@@ -214,6 +239,12 @@ dependencies = [
  "tokio-util",
 ]
 
+[[package]]
+name = "constant_time_eq"
+version = "0.3.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f7144d30dcf0fafbce74250a3963025d8d52177934239851c917d29f1df280c2"
+
 [[package]]
 name = "crossterm"
 version = "0.27.0"
@@ -1243,6 +1274,7 @@ checksum = "2047c6ded9c721764247e62cd3b03c09ffc529b2ba5b10ec482ae507a4a70160"
 name = "tcp-chat"
 version = "0.1.0"
 dependencies = [
+ "blake3",
  "color-eyre",
  "diesel",
  "futures",
diff --git a/server/Cargo.toml b/server/Cargo.toml
index e14a948..11f0817 100644
--- a/server/Cargo.toml
+++ b/server/Cargo.toml
@@ -12,6 +12,7 @@ path = "src/main.rs"
 path = "src/lib.rs"
 
 [dependencies]
+blake3 = "1.5.1"
 color-eyre = "0.6.3"
 diesel = { version = "2.1.6", features = ["postgres", "uuid", "r2d2"] }
 futures = "0.3.30"
diff --git a/server/src/services/registry.rs b/server/src/services/registry.rs
index 7810c67..cf39aa2 100644
--- a/server/src/services/registry.rs
+++ b/server/src/services/registry.rs
@@ -41,7 +41,7 @@ impl proto::registry_server::Registry for Registry {
         use diesel::query_dsl::methods::{FilterDsl, SelectDsl};
         use diesel::{ExpressionMethods, OptionalExtension, RunQueryDsl, SelectableHelper};
 
-        let credentials = request.into_inner();
+        let mut credentials = request.into_inner();
         let duplicate_user = users
             .filter(username.eq(&credentials.username))
             .select(User::as_select())
@@ -52,6 +52,9 @@ impl proto::registry_server::Registry for Registry {
         match duplicate_user {
             // No duplicate usernames found, registering a new account.
             None => {
+                // Hash the password using Blake3.
+                credentials.password = blake3::hash(credentials.password.as_bytes()).to_string();
+
                 let mut rng = self.rng.lock().await;
                 let user = User::new(credentials.username.clone(), credentials.password, &mut rng);
                 let _ = diesel::insert_into(users)
@@ -86,7 +89,11 @@ impl proto::registry_server::Registry for Registry {
         use diesel::query_dsl::methods::{FilterDsl, SelectDsl};
         use diesel::{ExpressionMethods, OptionalExtension, RunQueryDsl, SelectableHelper};
 
-        let credentials = request.into_inner();
+        let mut credentials = request.into_inner();
+
+        // Hash the password using Blake3.
+        credentials.password = blake3::hash(credentials.password.as_bytes()).to_string();
+
         let candidate_user = users
             .filter(username.eq(&credentials.username))
             .filter(password.eq(&credentials.password))