diff --git a/Cargo.lock b/Cargo.lock
index 68e6259e..bf8f1ed3 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -918,6 +918,19 @@ dependencies = [
  "want",
 ]
 
+[[package]]
+name = "hyper-tls"
+version = "0.5.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d6183ddfa99b85da61a140bea0efc93fdf56ceaa041b37d553518030827f9905"
+dependencies = [
+ "bytes",
+ "hyper",
+ "native-tls",
+ "tokio",
+ "tokio-native-tls",
+]
+
 [[package]]
 name = "idna"
 version = "0.2.3"
@@ -961,12 +974,27 @@ dependencies = [
  "cfg-if 1.0.0",
 ]
 
+[[package]]
+name = "ipnet"
+version = "2.3.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "68f2d64f2edebec4ce84ad108148e67e1064789bee435edc5b60ad398714a3a9"
+
 [[package]]
 name = "itoa"
 version = "0.4.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "dd25036021b0de88a0aff6b850051563c6516d0bf53f8638938edbb9de732736"
 
+[[package]]
+name = "js-sys"
+version = "0.3.55"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7cc9ffccd38c451a86bf13657df244e9c3f37493cce8e5e21e940963777acc84"
+dependencies = [
+ "wasm-bindgen",
+]
+
 [[package]]
 name = "lazy_static"
 version = "1.4.0"
@@ -1177,9 +1205,9 @@ dependencies = [
 
 [[package]]
 name = "native-tls"
-version = "0.2.7"
+version = "0.2.8"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b8d96b2e1c8da3957d58100b09f102c6d9cfdfced01b7ec5a8974044bb09dbd4"
+checksum = "48ba9f7719b5a0f42f338907614285fb5fd70e53858141f69898a1fb7203b24d"
 dependencies = [
  "lazy_static",
  "libc",
@@ -1744,6 +1772,41 @@ dependencies = [
  "winapi",
 ]
 
+[[package]]
+name = "reqwest"
+version = "0.11.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "51c732d463dd300362ffb44b7b125f299c23d2990411a4253824630ebc7467fb"
+dependencies = [
+ "base64",
+ "bytes",
+ "encoding_rs",
+ "futures-core",
+ "futures-util",
+ "http",
+ "http-body",
+ "hyper",
+ "hyper-tls",
+ "ipnet",
+ "js-sys",
+ "lazy_static",
+ "log",
+ "mime",
+ "native-tls",
+ "percent-encoding",
+ "pin-project-lite",
+ "serde",
+ "serde_json",
+ "serde_urlencoded",
+ "tokio",
+ "tokio-native-tls",
+ "url",
+ "wasm-bindgen",
+ "wasm-bindgen-futures",
+ "web-sys",
+ "winreg",
+]
+
 [[package]]
 name = "rocket"
 version = "0.5.0-rc.1"
@@ -2314,6 +2377,16 @@ dependencies = [
  "syn",
 ]
 
+[[package]]
+name = "tokio-native-tls"
+version = "0.3.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f7d995660bd2b7f8c1568414c1126076c13fbb725c40112dc0120b78eb9b717b"
+dependencies = [
+ "native-tls",
+ "tokio",
+]
+
 [[package]]
 name = "tokio-stream"
 version = "0.1.7"
@@ -2560,9 +2633,9 @@ checksum = "fd6fbd9a79829dd1ad0cc20627bf1ed606756a7f77edff7b66b7064f9cb327c6"
 
 [[package]]
 name = "wasm-bindgen"
-version = "0.2.75"
+version = "0.2.78"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b608ecc8f4198fe8680e2ed18eccab5f0cd4caaf3d83516fa5fb2e927fda2586"
+checksum = "632f73e236b219150ea279196e54e610f5dbafa5d61786303d4da54f84e47fce"
 dependencies = [
  "cfg-if 1.0.0",
  "wasm-bindgen-macro",
@@ -2570,9 +2643,9 @@ dependencies = [
 
 [[package]]
 name = "wasm-bindgen-backend"
-version = "0.2.75"
+version = "0.2.78"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "580aa3a91a63d23aac5b6b267e2d13cb4f363e31dce6c352fca4752ae12e479f"
+checksum = "a317bf8f9fba2476b4b2c85ef4c4af8ff39c3c7f0cdfeed4f82c34a880aa837b"
 dependencies = [
  "bumpalo",
  "lazy_static",
@@ -2583,11 +2656,23 @@ dependencies = [
  "wasm-bindgen-shared",
 ]
 
+[[package]]
+name = "wasm-bindgen-futures"
+version = "0.4.28"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8e8d7523cb1f2a4c96c1317ca690031b714a51cc14e05f712446691f413f5d39"
+dependencies = [
+ "cfg-if 1.0.0",
+ "js-sys",
+ "wasm-bindgen",
+ "web-sys",
+]
+
 [[package]]
 name = "wasm-bindgen-macro"
-version = "0.2.75"
+version = "0.2.78"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "171ebf0ed9e1458810dfcb31f2e766ad6b3a89dbda42d8901f2b268277e5f09c"
+checksum = "d56146e7c495528bf6587663bea13a8eb588d39b36b679d83972e1a2dbbdacf9"
 dependencies = [
  "quote",
  "wasm-bindgen-macro-support",
@@ -2595,9 +2680,9 @@ dependencies = [
 
 [[package]]
 name = "wasm-bindgen-macro-support"
-version = "0.2.75"
+version = "0.2.78"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "6c2657dd393f03aa2a659c25c6ae18a13a4048cebd220e147933ea837efc589f"
+checksum = "7803e0eea25835f8abdc585cd3021b3deb11543c6fe226dcd30b228857c5c5ab"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -2608,9 +2693,19 @@ dependencies = [
 
 [[package]]
 name = "wasm-bindgen-shared"
-version = "0.2.75"
+version = "0.2.78"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2e0c4a743a309662d45f4ede961d7afa4ba4131a59a639f29b0069c3798bbcc2"
+checksum = "0237232789cf037d5480773fe568aac745bfe2afbc11a863e97901780a6b47cc"
+
+[[package]]
+name = "web-sys"
+version = "0.3.55"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "38eb105f1c59d9eaa6b5cdc92b859d85b926e82cb2e0945cd0c9259faa6fe9fb"
+dependencies = [
+ "js-sys",
+ "wasm-bindgen",
+]
 
 [[package]]
 name = "winapi"
@@ -2634,6 +2729,15 @@ version = "0.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "712e227841d057c1ee1cd2fb22fa7e5a5461ae8e48fa2ca79ec42cfc1931183f"
 
+[[package]]
+name = "winreg"
+version = "0.7.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0120db82e8a1e0b9fb3345a539c478767c0048d842860994d96113d5b667bd69"
+dependencies = [
+ "winapi",
+]
+
 [[package]]
 name = "wyz"
 version = "0.2.0"
@@ -2665,6 +2769,7 @@ dependencies = [
  "pwhash",
  "rand 0.8.4",
  "regex",
+ "reqwest",
  "rocket",
  "rocket_sync_db_pools",
  "serde",
diff --git a/Cargo.toml b/Cargo.toml
index cf4d6fc2..3ade8473 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -19,6 +19,7 @@ urlencoding = "2.1"
 toml = "0.5"
 rand = "0.8"
 regex = "1.0"
+reqwest = { version = "0.11.0", features = [ "json" ] }
 rocket = { version = "0.5.0-rc.1", features = [ "json", "secrets" ] }
 serde = "1.0"
 serde_json = "1.0"
diff --git a/Rocket.toml b/Rocket.toml
index cae7034e..1ad0c463 100644
--- a/Rocket.toml
+++ b/Rocket.toml
@@ -17,6 +17,7 @@ maximum_pending_users = 25
 secret_key = "1vwCFFPSdQya895gNiO556SzmfShG6MokstgttLvwjw="
 bcrypt_cost = 4
 seed_database = true
+webhook_url = "http://localhost:8080/hook"
 
 [debug.databases.postgresql_database]
 url = "postgresql://zauth:zauth@localhost/zauth"
@@ -30,6 +31,7 @@ port = 8000
 # base_url =    # URL where the application is hosten (e.g. https://auth.zeus.gent)
 # mail_from =   # From header to set when sending emails (e.g. zauth@zeus.gent)
 # mail_server = # domain of the SMTP server used to send mail (e.g. smtp.zeus.gent)
+# webhook_url = # hook to post new (approved) user's details to
 
 # See src/config.rs for all the possible config values and their defaults
 
diff --git a/flake.nix b/flake.nix
index 09e32e73..be2a2b7b 100644
--- a/flake.nix
+++ b/flake.nix
@@ -22,7 +22,7 @@
   {
     devShell = mkShell {
       buildInputs = [
-        rust-bin.nightly.latest.default
+        (rust-bin.nightly.latest.default.override { extensions = [ "rust-analyzer-preview" "rust-src" ]; })
         openssl.dev
         pkg-config
         docker-compose
diff --git a/src/config.rs b/src/config.rs
index 6a6ea841..0d43f9dc 100644
--- a/src/config.rs
+++ b/src/config.rs
@@ -19,6 +19,7 @@ pub struct Config {
 	pub mail_from: String,
 	pub mail_server: String,
 	pub maximum_pending_users: usize,
+	pub webhook_url: Option<String>,
 }
 
 impl Config {
diff --git a/src/controllers/users_controller.rs b/src/controllers/users_controller.rs
index dcee6c7f..ad66d711 100644
--- a/src/controllers/users_controller.rs
+++ b/src/controllers/users_controller.rs
@@ -13,6 +13,7 @@ use crate::ephemeral::session::{
 };
 use crate::errors::Either::{self, Left, Right};
 use crate::errors::{InternalError, OneOf, Result, ZauthError};
+use crate::hooker::Hooker;
 use crate::mailer::Mailer;
 use crate::models::user::*;
 use crate::views::accepter::Accepter;
@@ -219,6 +220,7 @@ pub async fn set_approved<'r>(
 	username: String,
 	_session: AdminSession,
 	mailer: &'r State<Mailer>,
+	hooker: &'r State<Hooker>,
 	conf: &'r State<Config>,
 	db: DbConn,
 ) -> Result<impl Responder<'r, 'static>> {
@@ -227,6 +229,7 @@ pub async fn set_approved<'r>(
 
 	let login_url = uri!(conf.base_url(), new_session);
 
+	hooker.user_approved(&user).await?;
 	mailer
 		.create(
 			&user,
diff --git a/src/errors.rs b/src/errors.rs
index eae191e2..7c48aab2 100644
--- a/src/errors.rs
+++ b/src/errors.rs
@@ -10,6 +10,7 @@ use rocket::tokio::sync::mpsc::error::{SendError, TrySendError};
 use std::convert::Infallible;
 use validator::ValidationErrors;
 
+use crate::models::user::User;
 use crate::views::accepter::Accepter;
 
 #[derive(Error, Debug)]
@@ -203,6 +204,8 @@ pub enum InternalError {
 	InvalidEmail(#[from] lettre::address::AddressError),
 	#[error("Mailer error")]
 	MailError(#[from] lettre::error::Error),
+	#[error("Hooker stopped processing items")]
+	HookerStopped(#[from] SendError<User>),
 	#[error("Mailer stopped processing items")]
 	MailerStopped(#[from] SendError<Message>),
 	#[error("Mail queue full")]
diff --git a/src/hooker.rs b/src/hooker.rs
new file mode 100644
index 00000000..c53f86a0
--- /dev/null
+++ b/src/hooker.rs
@@ -0,0 +1,98 @@
+use crate::config::{AdminEmail, Config};
+use crate::errors::{InternalError, Result, ZauthError};
+use crate::mailer::Mailer;
+use crate::models::user::User;
+
+use askama::Template;
+use lettre::message::Mailbox;
+use rocket::tokio::sync::mpsc;
+use rocket::tokio::sync::mpsc::UnboundedReceiver;
+
+#[derive(Clone)]
+pub struct Hooker {
+	queue: mpsc::UnboundedSender<User>,
+}
+
+impl Hooker {
+	pub fn new(
+		config: &Config,
+		mailer: &Mailer,
+		admin_email: &AdminEmail,
+	) -> Result<Hooker> {
+		// Webhooks are only triggered by admin actions, so no need to worry
+		// about abuse
+		let (sender, recv) = mpsc::unbounded_channel();
+
+		if let Some(url) = &config.webhook_url {
+			rocket::tokio::spawn(Self::http_sender(
+				url.into(),
+				recv,
+				admin_email.0.clone(),
+				mailer.clone(),
+			));
+		} else {
+			rocket::tokio::spawn(Self::stub_sender(recv));
+		}
+
+		Ok(Hooker { queue: sender })
+	}
+
+	pub async fn user_approved(&self, user: &User) -> Result<()> {
+		self.queue
+			.send(user.clone())
+			.map_err(|e| ZauthError::from(InternalError::from(e)))
+	}
+
+	fn stub_sender(
+		mut receiver: UnboundedReceiver<User>,
+	) -> impl std::future::Future<Output = impl Send + 'static> {
+		async move {
+			// no URL configured, so we just drop the received users
+			while let Some(_) = receiver.recv().await {}
+		}
+	}
+
+	fn http_sender(
+		url: String,
+		mut receiver: UnboundedReceiver<User>,
+		admin_email: Mailbox,
+		mailer: Mailer,
+	) -> impl std::future::Future<Output = impl Send + 'static> {
+		async move {
+			let client = reqwest::Client::new();
+			while let Some(user) = receiver.recv().await {
+				if let Err(err) =
+					Self::do_send(&client, &url, &admin_email, &mailer, &user)
+						.await
+				{
+					println!("Error sending webhook: {:?}", err);
+				}
+			}
+		}
+	}
+
+	async fn do_send(
+		client: &reqwest::Client,
+		url: &str,
+		admin_email: &Mailbox,
+		mailer: &Mailer,
+		user: &User,
+	) -> Result<()> {
+		if let Err(err) = client.post(url.clone()).json(&user).send().await {
+			mailer
+				.create(
+					admin_email.clone(),
+					String::from("[Zauth] Confirm webhook failed"),
+					template!(
+						"mails/registration_webhook_failed.txt";
+						name: String = user.username.to_string(),
+						err: String = format!("{:?}", err),
+					)
+					.render()
+					.map_err(InternalError::from)?,
+				)
+				.await?;
+		}
+		Ok(())
+	}
+}
diff --git a/src/lib.rs b/src/lib.rs
index 6f0a8aac..4dbb03ae 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -31,6 +31,7 @@ pub mod controllers;
 pub mod db_seed;
 pub mod ephemeral;
 pub mod errors;
+pub mod hooker;
 pub mod http_authentication;
 pub mod mailer;
 pub mod models;
@@ -51,6 +52,7 @@ use crate::db_seed::Seeder;
 use crate::errors::{
 	internal_server_error, not_found, not_implemented, unauthorized,
 };
+use crate::hooker::Hooker;
 use crate::mailer::Mailer;
 use crate::token_store::TokenStore;
 
@@ -82,6 +84,7 @@ fn assemble(rocket: Rocket<Build>) -> Rocket<Build> {
 	);
 	let token_store = TokenStore::<oauth_controller::UserToken>::new(&config);
 	let mailer = Mailer::new(&config).unwrap();
+	let hooker = Hooker::new(&config, &mailer, &admin_email).unwrap();
 
 	let rocket = rocket
 		.mount(
@@ -133,6 +136,7 @@ fn assemble(rocket: Rocket<Build>) -> Rocket<Build> {
 		.mount("/static/", FileServer::from("static/"))
 		.manage(token_store)
 		.manage(mailer)
+		.manage(hooker)
 		.manage(admin_email)
 		.attach(DbConn::fairing())
 		.attach(AdHoc::config::<Config>())
diff --git a/templates/mails/registration_webhook_failed.txt b/templates/mails/registration_webhook_failed.txt
new file mode 100644
index 00000000..bcda7b77
--- /dev/null
+++ b/templates/mails/registration_webhook_failed.txt
@@ -0,0 +1,10 @@
+Hi admins
+
+The webhook for when a new user was approved failed for {{name}}. You will probably have to do some manual work to register the user in the other applications.
+
+This was the error produced by reqwest, hopefully it helps:
+
+{{err}}
+
+Kind regards
+The Zeus Authentication Server
diff --git a/test_client/hook_server.py b/test_client/hook_server.py
new file mode 100644
index 00000000..f0923d9e
--- /dev/null
+++ b/test_client/hook_server.py
@@ -0,0 +1,48 @@
+#!/usr/bin/env python3
+"""
+Very simple HTTP server in python for logging requests
+Usage::
+    ./server.py [<port>]
+"""
+from http.server import BaseHTTPRequestHandler, HTTPServer
+import logging
+
+class S(BaseHTTPRequestHandler):
+    def _set_response(self):
+        self.send_response(200)
+        self.send_header('Content-type', 'text/html')
+        self.end_headers()
+
+    def do_GET(self):
+        logging.info("GET request,\nPath: %s\nHeaders:\n%s\n", str(self.path), str(self.headers))
+        self._set_response()
+        self.wfile.write("GET request for {}".format(self.path).encode('utf-8'))
+
+    def do_POST(self):
+        content_length = int(self.headers['Content-Length']) # <--- Gets the size of data
+        post_data = self.rfile.read(content_length) # <--- Gets the data itself
+        logging.info("POST request,\nPath: %s\nHeaders:\n%s\n\nBody:\n%s\n",
+                str(self.path), str(self.headers), post_data.decode('utf-8'))
+
+        self._set_response()
+        self.wfile.write("POST request for {}".format(self.path).encode('utf-8'))
+
+def run(server_class=HTTPServer, handler_class=S, port=8080):
+    logging.basicConfig(level=logging.INFO)
+    server_address = ('', port)
+    httpd = server_class(server_address, handler_class)
+    logging.info('Starting httpd...\n')
+    try:
+        httpd.serve_forever()
+    except KeyboardInterrupt:
+        pass
+    httpd.server_close()
+    logging.info('Stopping httpd...\n')
+
+if __name__ == '__main__':
+    from sys import argv
+
+    if len(argv) == 2:
+        run(port=int(argv[1]))
+    else:
+        run()
diff --git a/tests/common/mod.rs b/tests/common/mod.rs
index 0cab7bd8..790dce65 100644
--- a/tests/common/mod.rs
+++ b/tests/common/mod.rs
@@ -50,6 +50,7 @@ pub fn config() -> Config {
 		mail_from: "zauth@example.com".to_string(),
 		mail_server: "stub".to_string(),
 		maximum_pending_users: 5,
+		webhook_url: None,
 	}
 }