diff --git a/Cargo.toml b/Cargo.toml
index ee13d82..f60d02b 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -19,7 +19,7 @@ actix-service = "2.0.0"
 actix-web = "4.0.0-beta.6"
 anyhow = "*"
 clap = "3.0.0-beta.2"
-chrono = "*"
+chrono = { version = "*", features = [ "serde" ]}
 futures = "*"
 futures-util = "*"
 http = "*"
@@ -38,6 +38,7 @@ async-trait = "0.1.48"
 sea-query = { version = "0.9.4", features = [ "with-chrono" ] }
 lldap_model = { path = "model" }
 lldap_app = { path = "app" }
+serde_json = "1.0.64"
 
 [dependencies.figment]
 features = ["toml", "env"]
diff --git a/app/src/app.rs b/app/src/app.rs
index 38b77d8..89770a2 100644
--- a/app/src/app.rs
+++ b/app/src/app.rs
@@ -8,6 +8,7 @@ pub enum Msg {
     ListUsersRequest(ListUsersRequest),
 }
 
+
 impl Component for App {
     type Message = Msg;
     type Properties = ();
diff --git a/model/Cargo.toml b/model/Cargo.toml
index f4528de..b3b1c59 100644
--- a/model/Cargo.toml
+++ b/model/Cargo.toml
@@ -8,7 +8,7 @@ edition = "2018"
 js = []
 
 [dependencies]
-chrono = "*"
+chrono = { version = "*", features = [ "serde" ]}
 serde = "*"
 
 [target.'cfg(not(target_arch = "wasm32"))'.dependencies]
diff --git a/model/src/lib.rs b/model/src/lib.rs
index ba87c7b..2bac1a2 100644
--- a/model/src/lib.rs
+++ b/model/src/lib.rs
@@ -1,10 +1,12 @@
-#[derive(PartialEq, Eq, Debug)]
+use serde::{Serialize, Deserialize};
+
+#[derive(PartialEq, Eq, Debug, Serialize, Deserialize)]
 pub struct BindRequest {
     pub name: String,
     pub password: String,
 }
 
-#[derive(PartialEq, Eq, Debug)]
+#[derive(PartialEq, Eq, Debug, Serialize, Deserialize)]
 pub enum RequestFilter {
     And(Vec<RequestFilter>),
     Or(Vec<RequestFilter>),
@@ -12,12 +14,12 @@ pub enum RequestFilter {
     Equality(String, String),
 }
 
-#[derive(PartialEq, Eq, Debug)]
+#[derive(PartialEq, Eq, Debug, Serialize, Deserialize)]
 pub struct ListUsersRequest {
     pub filters: Option<RequestFilter>,
 }
 
-#[derive(PartialEq, Eq, Debug)]
+#[derive(PartialEq, Eq, Debug, Serialize, Deserialize)]
 #[cfg_attr(not(target_arch = "wasm32"), derive(sqlx::FromRow))]
 pub struct User {
     pub user_id: String,
@@ -29,7 +31,7 @@ pub struct User {
     pub creation_date: chrono::NaiveDateTime,
 }
 
-#[derive(PartialEq, Eq, Debug)]
+#[derive(PartialEq, Eq, Debug, Serialize, Deserialize)]
 pub struct Group {
     pub display_name: String,
     pub users: Vec<String>,
diff --git a/src/infra/tcp_server.rs b/src/infra/tcp_server.rs
index 7d5c022..dfec54c 100644
--- a/src/infra/tcp_server.rs
+++ b/src/infra/tcp_server.rs
@@ -4,7 +4,7 @@ use actix_files::{Files, NamedFile};
 use actix_http::HttpServiceBuilder;
 use actix_server::ServerBuilder;
 use actix_service::map_config;
-use actix_web::{dev::AppConfig, web, App, HttpRequest};
+use actix_web::{dev::AppConfig, web, App, HttpRequest, HttpResponse};
 use anyhow::{Context, Result};
 use std::path::PathBuf;
 
@@ -16,6 +16,34 @@ async fn index(req: HttpRequest) -> actix_web::Result<NamedFile> {
     Ok(NamedFile::open(path)?)
 }
 
+type ApiResult<M> = actix_web::Either<web::Json<M>, HttpResponse>;
+
+async fn user_list_handler(_info: web::Json<ListUsersRequest>) -> ApiResult<Vec<User>> {
+    if true {
+        ApiResult::Right(HttpResponse::Conflict().finish())
+    } else {
+        ApiResult::Left(web::Json(Vec::<User>::new()))
+    }
+}
+
+fn api_config(cfg: &mut web::ServiceConfig) {
+    let json_config = web::JsonConfig::default()
+        .limit(4096)
+        .error_handler(|err, _req| {
+            // create custom error response
+            actix_web::error::InternalError::from_response(
+                err,
+                HttpResponse::Conflict().finish().into(),
+            )
+            .into()
+        });
+    cfg.service(
+        web::resource("/users")
+            .app_data(json_config)
+            .route(web::post().to(user_list_handler)),
+    );
+}
+
 pub fn build_tcp_server<Backend>(
     config: &Configuration,
     _backend_handler: Backend,
@@ -34,6 +62,8 @@ where
                             "/{filename:(index\\.html|main\\.js)?}",
                             web::get().to(index),
                         )
+                        // API endpoint.
+                        .service(web::scope("/api").configure(api_config))
                         // Serve the /pkg path with the compiled WASM app.
                         .service(Files::new("/pkg", "./app/pkg")),
                     |_| AppConfig::default(),