diff --git a/Cargo.toml b/Cargo.toml
index 3eeeb8a..f1771f4 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "aliurl"
-version = "0.3.2"
+version = "0.3.3"
 edition = "2021"
 license = "MIT"
 repository = "https://github.com/ivabus/aliurl"
diff --git a/src/main.rs b/src/main.rs
index 4bf296d..7477ff0 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -50,7 +50,17 @@ struct Alias {
 	redirect_with_ad: Option<bool>,
 }
 
+fn lock() {
+	while std::path::Path::new("./alias.json.lock").exists() {}
+	std::fs::File::create("./alias.json.lock").unwrap();
+}
+
+fn unlock() {
+	std::fs::remove_file("./alias.json.lock").unwrap()
+}
+
 fn read_aliases() -> Vec<Alias> {
+	lock();
 	if !std::path::Path::new("./alias.json").exists() {
 		let mut file = std::fs::File::create("./alias.json").unwrap();
 		file.write_all(b"[]").unwrap();
@@ -66,6 +76,7 @@ fn read_aliases() -> Vec<Alias> {
 	let mut contents = String::new();
 	buf_reader.read_to_string(&mut contents).unwrap();
 	let aliases_list: Vec<Alias> = serde_json::from_str(&contents).unwrap();
+	unlock();
 	aliases_list
 }
 
diff --git a/src/post.rs b/src/post.rs
index 1c1977e..53a163f 100644
--- a/src/post.rs
+++ b/src/post.rs
@@ -71,7 +71,7 @@ fn check_access_key(key: Option<String>) -> Result<String, (Status, RawJson<Stri
 }
 
 #[post("/api/create_alias", data = "<data>")]
-pub fn create_alias(data: &RawStr) -> (Status, RawJson<String>) {
+pub async fn create_alias(data: &RawStr) -> (Status, RawJson<String>) {
 	let data: CreateAliasRequest = match serde_json::from_str(&data.to_string()) {
 		Ok(req) => req,
 		Err(e) => {
@@ -82,8 +82,8 @@ pub fn create_alias(data: &RawStr) -> (Status, RawJson<String>) {
 	if let Err(e) = check_access_key(data.access_key) {
 		return e;
 	}
-
 	let mut aliases_list = read_aliases();
+	lock();
 	let mut file = std::fs::File::options().write(true).open("./alias.json").unwrap();
 	let alias = match data.alias {
 		None => {
@@ -128,12 +128,13 @@ pub fn create_alias(data: &RawStr) -> (Status, RawJson<String>) {
 
 	file.write_all(serde_json::to_string(&aliases_list).unwrap().as_bytes()).unwrap();
 	file.sync_all().unwrap();
+	unlock();
 
 	return (Status::Ok, RawJson(serde_json::to_string(&alias).unwrap()));
 }
 
 #[post("/api/get_aliases", data = "<data>")]
-pub fn get_aliases(data: &RawStr) -> (Status, RawJson<String>) {
+pub async fn get_aliases(data: &RawStr) -> (Status, RawJson<String>) {
 	let data: GetAliasesRequest = match serde_json::from_str(&data.to_string()) {
 		Ok(req) => req,
 		Err(e) => {
@@ -149,7 +150,7 @@ pub fn get_aliases(data: &RawStr) -> (Status, RawJson<String>) {
 }
 
 #[post("/api/remove_alias", data = "<data>")]
-pub fn remove_alias(data: &RawStr) -> (Status, RawJson<String>) {
+pub async fn remove_alias(data: &RawStr) -> (Status, RawJson<String>) {
 	let data: RemoveAliasRequest = match serde_json::from_str(&data.to_string()) {
 		Ok(req) => req,
 		Err(e) => {
@@ -161,6 +162,7 @@ pub fn remove_alias(data: &RawStr) -> (Status, RawJson<String>) {
 	}
 	let mut aliases_list = read_aliases();
 	let mut removed_aliases: Vec<Alias> = vec![];
+	lock();
 	let mut file = std::fs::File::options().write(true).open("./alias.json").unwrap();
 
 	for i in (0..aliases_list.len()).rev() {
@@ -172,6 +174,7 @@ pub fn remove_alias(data: &RawStr) -> (Status, RawJson<String>) {
 	file.write_all(&aliases_list.as_bytes()).unwrap();
 	file.set_len(aliases_list.as_bytes().len() as u64).unwrap();
 	file.sync_all().unwrap();
+	unlock();
 
 	return (Status::Ok, RawJson(serde_json::to_string(&removed_aliases).unwrap()));
 }