diff --git a/Cargo.lock b/Cargo.lock
index 9458aa2..0459a5b 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -119,6 +119,20 @@ version = "1.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "baf1de4339761588bc0619e3cbc0120ee582ebb74b53b4efbf79117bd2da40fd"
 
+[[package]]
+name = "combine"
+version = "4.6.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "35ed6e9d84f0b51a7f52daf1c7d71dd136fd7a3f41a8462b8cdb8c78d920fad4"
+dependencies = [
+ "bytes",
+ "futures-core",
+ "memchr",
+ "pin-project-lite",
+ "tokio",
+ "tokio-util",
+]
+
 [[package]]
 name = "fnv"
 version = "1.0.7"
@@ -149,6 +163,12 @@ version = "0.3.28"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "4bca583b7e26f571124fe5b7561d49cb2868d79116cfa0eefce955557c6fee8c"
 
+[[package]]
+name = "futures-sink"
+version = "0.3.28"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f43be4fe21a13b9781a69afa4985b0f6ee0e1afab2c6f454a8cf30e2b2237b6e"
+
 [[package]]
 name = "futures-task"
 version = "0.3.28"
@@ -162,6 +182,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "26b01e40b772d54cf6c6d721c1d1abd0647a0106a12ecaa1c186273392a69533"
 dependencies = [
  "futures-core",
+ "futures-sink",
  "futures-task",
  "pin-project-lite",
  "pin-utils",
@@ -239,6 +260,16 @@ dependencies = [
  "want",
 ]
 
+[[package]]
+name = "idna"
+version = "0.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7d20d6b07bfbc108882d88ed8e37d39636dcc260e15e30c45e6ba089610b917c"
+dependencies = [
+ "unicode-bidi",
+ "unicode-normalization",
+]
+
 [[package]]
 name = "itoa"
 version = "1.0.9"
@@ -250,6 +281,7 @@ name = "kosyncrs"
 version = "0.1.0"
 dependencies = [
  "axum",
+ "redis",
  "serde",
  "serde_json",
  "tokio",
@@ -386,6 +418,27 @@ dependencies = [
  "proc-macro2",
 ]
 
+[[package]]
+name = "redis"
+version = "0.23.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "4f49cdc0bb3f412bf8e7d1bd90fe1d9eb10bc5c399ba90973c14662a27b3f8ba"
+dependencies = [
+ "async-trait",
+ "bytes",
+ "combine",
+ "futures-util",
+ "itoa",
+ "percent-encoding",
+ "pin-project-lite",
+ "ryu",
+ "sha1_smol",
+ "socket2 0.4.9",
+ "tokio",
+ "tokio-util",
+ "url",
+]
+
 [[package]]
 name = "rustc-demangle"
 version = "0.1.23"
@@ -457,6 +510,12 @@ dependencies = [
  "serde",
 ]
 
+[[package]]
+name = "sha1_smol"
+version = "1.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ae1a47186c03a32177042e55dbc5fd5aee900b8e0069a8d70fba96a9375cd012"
+
 [[package]]
 name = "socket2"
 version = "0.4.9"
@@ -494,6 +553,21 @@ version = "0.1.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "2047c6ded9c721764247e62cd3b03c09ffc529b2ba5b10ec482ae507a4a70160"
 
+[[package]]
+name = "tinyvec"
+version = "1.6.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "87cc5ceb3875bb20c2890005a4e226a4651264a5c75edb2421b52861a0a0cb50"
+dependencies = [
+ "tinyvec_macros",
+]
+
+[[package]]
+name = "tinyvec_macros"
+version = "0.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1f3ccbac311fea05f86f61904b462b55fb3df8837a366dfc601a0161d0532f20"
+
 [[package]]
 name = "tokio"
 version = "1.32.0"
@@ -501,6 +575,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "17ed6077ed6cd6c74735e21f37eb16dc3935f96878b1fe961074089cc80893f9"
 dependencies = [
  "backtrace",
+ "bytes",
  "libc",
  "mio",
  "num_cpus",
@@ -521,6 +596,20 @@ dependencies = [
  "syn",
 ]
 
+[[package]]
+name = "tokio-util"
+version = "0.7.9"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1d68074620f57a0b21594d9735eb2e98ab38b17f80d3fcb189fca266771ca60d"
+dependencies = [
+ "bytes",
+ "futures-core",
+ "futures-sink",
+ "pin-project-lite",
+ "tokio",
+ "tracing",
+]
+
 [[package]]
 name = "tower"
 version = "0.4.13"
@@ -576,12 +665,38 @@ version = "0.2.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "3528ecfd12c466c6f163363caf2d02a71161dd5e1cc6ae7b34207ea2d42d81ed"
 
+[[package]]
+name = "unicode-bidi"
+version = "0.3.13"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "92888ba5573ff080736b3648696b70cafad7d250551175acbaa4e0385b3e1460"
+
 [[package]]
 name = "unicode-ident"
 version = "1.0.12"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "3354b9ac3fae1ff6755cb6db53683adb661634f67557942dea4facebec0fee4b"
 
+[[package]]
+name = "unicode-normalization"
+version = "0.1.22"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5c5713f0fc4b5db668a2ac63cdb7bb4469d8c9fed047b1d0292cc7b0ce2ba921"
+dependencies = [
+ "tinyvec",
+]
+
+[[package]]
+name = "url"
+version = "2.4.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "143b538f18257fac9cad154828a57c6bf5157e1aa604d4816b5995bf6de87ae5"
+dependencies = [
+ "form_urlencoded",
+ "idna",
+ "percent-encoding",
+]
+
 [[package]]
 name = "want"
 version = "0.3.1"
diff --git a/Cargo.toml b/Cargo.toml
index 9ce402b..1e8a777 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -7,6 +7,7 @@ edition = "2021"
 
 [dependencies]
 axum = "0.6.20"
-serde = "1.0.188"
+redis = { version = "0.23.3", features = ["tokio-comp"] }
+serde = { version = "1.0.188", features = ["derive"] }
 serde_json = "1.0.107"
 tokio = { version = "1.32.0", features = ["macros", "rt-multi-thread"] }
diff --git a/src/main.rs b/src/main.rs
index ceabda4..83a049f 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -2,6 +2,16 @@ use axum::{http::StatusCode, routing::get, routing::post, routing::put, Json, Ro
 
 use serde_json::{json, Value};
 
+use serde::Deserialize;
+
+use redis::Commands;
+
+#[derive(Deserialize)]
+pub struct CreateUser {
+    username: String,
+    password: String,
+}
+
 #[tokio::main]
 async fn main() {
     // build our application with a single route
@@ -24,7 +34,28 @@ async fn root() -> &'static str {
     "KOreader sync server"
 }
 
-async fn create_user() {}
+async fn create_user(Json(payload): Json<CreateUser>) -> (StatusCode, String) {
+    let client = redis::Client::open("redis://127.0.0.1/").unwrap();
+    let mut con = client.get_connection().unwrap();
+
+    let username = payload.username;
+    let password = payload.password;
+
+    let user_key = format!("user:{username}:key");
+
+    let does_exist: bool = con.exists(&user_key).unwrap();
+
+    if does_exist == false {
+        let _: () = con.set(&user_key, password).unwrap();
+    } else {
+        return (
+            StatusCode::PAYMENT_REQUIRED,
+            "Username is already registered.".to_owned(),
+        );
+    }
+
+    (StatusCode::CREATED, format!("username = {username}"))
+}
 
 async fn auth_user() {}
 
@@ -33,5 +64,5 @@ async fn update_progress() {}
 async fn get_progress() {}
 
 async fn healthcheck() -> (StatusCode, Json<Value>) {
-    (StatusCode::OK, Json(json!({ "state": "OK" })))
+    (StatusCode::OK, Json(json!({ "state" : "OK" })))
 }