diff --git a/Cargo.lock b/Cargo.lock
index 3cf2f62..729c43f 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -39,8 +39,8 @@ dependencies = [
  "encoding_rs",
  "flate2",
  "futures-core",
- "h2",
- "http",
+ "h2 0.3.26",
+ "http 0.2.12",
  "httparse",
  "httpdate",
  "itoa",
@@ -91,7 +91,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d22475596539443685426b6bdadb926ad0ecaefdfc5fb05e5e3441f15463c511"
 dependencies = [
  "bytestring",
- "http",
+ "http 0.2.12",
  "regex",
  "serde",
  "tracing",
@@ -396,6 +396,12 @@ dependencies = [
  "num-traits",
 ]
 
+[[package]]
+name = "atomic-waker"
+version = "1.1.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1505bd5d3d116872e7271a6d4e16d81d0c8570876c8de68093a09ac269d8aac0"
+
 [[package]]
 name = "autocfg"
 version = "1.3.0"
@@ -1389,7 +1395,26 @@ dependencies = [
  "futures-core",
  "futures-sink",
  "futures-util",
- "http",
+ "http 0.2.12",
+ "indexmap",
+ "slab",
+ "tokio",
+ "tokio-util",
+ "tracing",
+]
+
+[[package]]
+name = "h2"
+version = "0.4.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "fa82e28a107a8cc405f0839610bdc9b15f1e25ec7d696aa5cf173edbcb1486ab"
+dependencies = [
+ "atomic-waker",
+ "bytes",
+ "fnv",
+ "futures-core",
+ "futures-sink",
+ "http 1.1.0",
  "indexmap",
  "slab",
  "tokio",
@@ -1495,6 +1520,40 @@ dependencies = [
  "itoa",
 ]
 
+[[package]]
+name = "http"
+version = "1.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "21b9ddb458710bc376481b842f5da65cdf31522de232c1ca8146abce2a358258"
+dependencies = [
+ "bytes",
+ "fnv",
+ "itoa",
+]
+
+[[package]]
+name = "http-body"
+version = "1.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1cac85db508abc24a2e48553ba12a996e87244a0395ce011e62b37158745d643"
+dependencies = [
+ "bytes",
+ "http 1.1.0",
+]
+
+[[package]]
+name = "http-body-util"
+version = "0.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0475f8b2ac86659c21b64320d5d653f9efe42acd2a4e560073ec61a155a34f1d"
+dependencies = [
+ "bytes",
+ "futures-core",
+ "http 1.1.0",
+ "http-body",
+ "pin-project-lite",
+]
+
 [[package]]
 name = "httparse"
 version = "1.8.0"
@@ -1522,6 +1581,62 @@ version = "2.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "9a3a5bfb195931eeb336b2a7b4d761daec841b97f947d34394601737a7bba5e4"
 
+[[package]]
+name = "hyper"
+version = "1.3.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "fe575dd17d0862a9a33781c8c4696a55c320909004a67a00fb286ba8b1bc496d"
+dependencies = [
+ "bytes",
+ "futures-channel",
+ "futures-util",
+ "h2 0.4.5",
+ "http 1.1.0",
+ "http-body",
+ "httparse",
+ "itoa",
+ "pin-project-lite",
+ "smallvec",
+ "tokio",
+ "want",
+]
+
+[[package]]
+name = "hyper-tls"
+version = "0.6.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "70206fc6890eaca9fde8a0bf71caa2ddfc9fe045ac9e5c70df101a7dbde866e0"
+dependencies = [
+ "bytes",
+ "http-body-util",
+ "hyper",
+ "hyper-util",
+ "native-tls",
+ "tokio",
+ "tokio-native-tls",
+ "tower-service",
+]
+
+[[package]]
+name = "hyper-util"
+version = "0.1.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ca38ef113da30126bbff9cd1705f9273e15d45498615d138b0c20279ac7a76aa"
+dependencies = [
+ "bytes",
+ "futures-channel",
+ "futures-util",
+ "http 1.1.0",
+ "http-body",
+ "hyper",
+ "pin-project-lite",
+ "socket2",
+ "tokio",
+ "tower",
+ "tower-service",
+ "tracing",
+]
+
 [[package]]
 name = "iana-time-zone"
 version = "0.1.60"
@@ -1612,6 +1727,12 @@ dependencies = [
  "generic-array",
 ]
 
+[[package]]
+name = "ipnet"
+version = "2.9.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8f518f335dce6725a761382244631d86cf0ccb2863413590b31338feb467f9c3"
+
 [[package]]
 name = "is-terminal"
 version = "0.4.12"
@@ -2500,6 +2621,48 @@ version = "0.8.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "adad44e29e4c806119491a7f06f03de4d1af22c3a680dd47f1e6e179439d1f56"
 
+[[package]]
+name = "reqwest"
+version = "0.12.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "566cafdd92868e0939d3fb961bd0dc25fcfaaed179291093b3d43e6b3150ea10"
+dependencies = [
+ "base64 0.22.1",
+ "bytes",
+ "encoding_rs",
+ "futures-core",
+ "futures-util",
+ "h2 0.4.5",
+ "http 1.1.0",
+ "http-body",
+ "http-body-util",
+ "hyper",
+ "hyper-tls",
+ "hyper-util",
+ "ipnet",
+ "js-sys",
+ "log",
+ "mime",
+ "native-tls",
+ "once_cell",
+ "percent-encoding",
+ "pin-project-lite",
+ "rustls-pemfile 2.1.2",
+ "serde",
+ "serde_json",
+ "serde_urlencoded",
+ "sync_wrapper",
+ "system-configuration",
+ "tokio",
+ "tokio-native-tls",
+ "tower-service",
+ "url",
+ "wasm-bindgen",
+ "wasm-bindgen-futures",
+ "web-sys",
+ "winreg",
+]
+
 [[package]]
 name = "ring"
 version = "0.17.8"
@@ -3233,6 +3396,33 @@ dependencies = [
  "unicode-ident",
 ]
 
+[[package]]
+name = "sync_wrapper"
+version = "0.1.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2047c6ded9c721764247e62cd3b03c09ffc529b2ba5b10ec482ae507a4a70160"
+
+[[package]]
+name = "system-configuration"
+version = "0.5.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ba3a3adc5c275d719af8cb4272ea1c4a6d668a777f37e115f6d11ddbc1c8e0e7"
+dependencies = [
+ "bitflags 1.3.2",
+ "core-foundation",
+ "system-configuration-sys",
+]
+
+[[package]]
+name = "system-configuration-sys"
+version = "0.5.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a75fb188eb626b924683e3b95e3a48e63551fcfb51949de2f06a9d91dbee93c9"
+dependencies = [
+ "core-foundation-sys",
+ "libc",
+]
+
 [[package]]
 name = "tempfile"
 version = "3.10.1"
@@ -3476,6 +3666,34 @@ dependencies = [
  "winnow",
 ]
 
+[[package]]
+name = "tower"
+version = "0.4.13"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b8fa9be0de6cf49e536ce1851f987bd21a43b771b09473c3549a6c853db37c1c"
+dependencies = [
+ "futures-core",
+ "futures-util",
+ "pin-project",
+ "pin-project-lite",
+ "tokio",
+ "tower-layer",
+ "tower-service",
+ "tracing",
+]
+
+[[package]]
+name = "tower-layer"
+version = "0.3.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c20c8dbed6283a09604c3e69b4b7eeb54e298b8a600d4d5ecb5ad39de609f1d0"
+
+[[package]]
+name = "tower-service"
+version = "0.3.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b6bc1c9ce2b5135ac7f93c72918fc37feb872bdc6a5533a8b85eb4b86bfdae52"
+
 [[package]]
 name = "tracing"
 version = "0.1.40"
@@ -3521,6 +3739,12 @@ dependencies = [
  "once_cell",
 ]
 
+[[package]]
+name = "try-lock"
+version = "0.2.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e421abadd41a4225275504ea4d6566923418b7f05506fbc9c0fe86ba7396114b"
+
 [[package]]
 name = "typenum"
 version = "1.17.0"
@@ -3757,8 +3981,10 @@ dependencies = [
  "mockall",
  "pretty_env_logger",
  "rand",
+ "reqwest",
  "rust-embed",
  "serde",
+ "serde_json",
  "sqlx",
  "tera",
  "time",
@@ -3790,6 +4016,15 @@ dependencies = [
  "winapi-util",
 ]
 
+[[package]]
+name = "want"
+version = "0.3.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "bfa7760aed19e106de2c7c0b581b509f2f25d3dacaf737cb82ac61bc6d760b0e"
+dependencies = [
+ "try-lock",
+]
+
 [[package]]
 name = "wasi"
 version = "0.11.0+wasi-snapshot-preview1"
@@ -3827,6 +4062,18 @@ dependencies = [
  "wasm-bindgen-shared",
 ]
 
+[[package]]
+name = "wasm-bindgen-futures"
+version = "0.4.42"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "76bc14366121efc8dbb487ab05bcc9d346b3b5ec0eaa76e46594cabbe51762c0"
+dependencies = [
+ "cfg-if",
+ "js-sys",
+ "wasm-bindgen",
+ "web-sys",
+]
+
 [[package]]
 name = "wasm-bindgen-macro"
 version = "0.2.92"
@@ -3856,6 +4103,16 @@ version = "0.2.92"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "af190c94f2773fdb3729c55b007a722abb5384da03bc0986df4c289bf5567e96"
 
+[[package]]
+name = "web-sys"
+version = "0.3.69"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "77afa9a11836342370f4817622a2f0f418b134426d91a82dfb48f532d2ec13ef"
+dependencies = [
+ "js-sys",
+ "wasm-bindgen",
+]
+
 [[package]]
 name = "webpki-roots"
 version = "0.25.4"
@@ -4069,6 +4326,16 @@ dependencies = [
  "memchr",
 ]
 
+[[package]]
+name = "winreg"
+version = "0.52.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a277a57398d4bfa075df44f501a17cfdf8542d224f0d36095a2adc7aee4ef0a5"
+dependencies = [
+ "cfg-if",
+ "windows-sys 0.48.0",
+]
+
 [[package]]
 name = "yaml-rust"
 version = "0.4.5"
diff --git a/Cargo.toml b/Cargo.toml
index 13dc5d5..3272e81 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -33,3 +33,7 @@ tracing = { version = "0.1.40", features = ["log"] }
 tracing-actix-web = "0.7.10"
 url = { version = "2.5.0", features = ["serde"] }
 validator = { version = "0.18.1", features = ["derive"] }
+
+[dev-dependencies]
+reqwest = { version = "0.12.4", features = ["json"] }
+serde_json = "1.0.117"
diff --git a/src/identity/adapters/output/mailer/lettre/account_validation_link.rs b/src/identity/adapters/output/mailer/lettre/account_validation_link.rs
index 01d5f45..ecdeeec 100644
--- a/src/identity/adapters/output/mailer/lettre/account_validation_link.rs
+++ b/src/identity/adapters/output/mailer/lettre/account_validation_link.rs
@@ -2,6 +2,8 @@
 //
 // SPDX-License-Identifier: AGPL-3.0-or-later
 
+use lettre::{message::header::ContentType, AsyncTransport, Message};
+
 use super::*;
 use crate::identity::application::port::output::mailer::{account_validation_link::*, errors::*};
 
@@ -13,53 +15,83 @@ impl AccountValidationLinkOutMailerPort for LettreMailer {
         username: &str,
         validation_secret: &str,
     ) -> OutMailerPortResult<()> {
-
         let email = Message::builder()
-            .from(&self.from)
-            .reply_to(&self.reply_to)
-            .to(to)
-            .subject("Please validate your account on Vanikam") // TODO: use better title
+            .from(self.from.parse().unwrap())
+            .reply_to(self.reply_to.parse().unwrap())
+            .to(format!("{username} <{to}>").parse().unwrap())
+            .subject("Please verify your account on Vanikam") // TODO: use better title
             .header(ContentType::TEXT_PLAIN)
-            .body(format!(r#"Hello {username},
-            Please click here to validate your Vanikam account: {validation_secret}
+            .body(format!(
+                r#"Hello {username},
+            Please click here to verify your Vanikam account: {validation_secret}
             Warm regards,
             Vanikam Admin
-            "#)) // TODO: change signature
+            "#
+            )) // TODO: change signature
             .unwrap();
-            mailer.send(email).await.unwrap();
+        self.mailer.send(email).await.unwrap();
 
+        Ok(())
     }
 }
-// TODO: mailer tests
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use reqwest::Client;
+    use url::Url;
 
-//#[cfg(test)]
-//mod tests {
-//    use super::*;
-//
-//    #[actix_rt::test]
-//    async fn test_postgres_create_verification_secret() {
-//        let settings = crate::settings::tests::get_settings().await;
-//        let db = super::DBOutPostgresAdapter::new(
-//            sqlx::postgres::PgPool::connect(&settings.database.url)
-//                .await
-//                .unwrap(),
-//        );
-//
-//        let msg = CreateSecretMsgBuilder::default()
-//            .secret("secret".into())
-//            .purpose("purpose".into())
-//            .username("username".into())
-//            .build()
-//            .unwrap();
-//
-//        db.create_verification_secret(msg.clone()).await.unwrap();
-//
-//        // duplicate: secret exists
-//        assert_eq!(
-//            db.create_verification_secret(msg).await.err(),
-//            Some(OutDBPortError::VerificationOTPSecretExists)
-//        );
-//
-//        settings.drop_db().await;
-//    }
-//}
+    use serde::Deserialize;
+
+    #[derive(Deserialize, Clone)]
+    struct MaildevAddress {
+        address: String,
+        name: String,
+    }
+    #[derive(Deserialize, Clone)]
+    struct MaildevEmail {
+        id: String,
+        from: Vec<MaildevAddress>,
+        to: Vec<MaildevAddress>,
+        subject: String,
+        text: String,
+        html: Option<String>,
+    }
+
+    #[actix_rt::test]
+    async fn test_mailer_account_validation_link() {
+        let username = "batman";
+        let email = "batman@account_validation_link.example.com";
+        let validation_secret = "dafsdfasecret";
+
+        let settings = crate::settings::tests::get_settings().await;
+        let m = LettreMailer::new(&settings).await;
+
+        m.account_validation_link(email, username, validation_secret)
+            .await
+            .unwrap();
+
+        let c = Client::default();
+
+        let maildev_url =
+            std::env::var("MAILDEV_URL").expect("Please set maildev instance URL in MAILDEV_URL");
+
+        let mut u = Url::parse(&maildev_url).unwrap();
+
+        u.set_path("/email");
+        let maildev_emails: Vec<MaildevEmail> =
+            c.get(u.clone()).send().await.unwrap().json().await.unwrap();
+        let maildev_email = maildev_emails
+            .iter()
+            .find(|e| e.to.iter().any(|f| f.address == email))
+            .unwrap();
+        assert!(maildev_email.text.contains(validation_secret));
+        assert!(maildev_email.text.contains(username));
+        assert!(maildev_email
+            .to
+            .iter()
+            .any(|t| t.address == email && t.name == username));
+
+        u.set_path(&format!("/email/{}", maildev_email.id));
+        c.delete(u).send().await.unwrap();
+    }
+}
diff --git a/src/identity/adapters/output/mailer/lettre/mod.rs b/src/identity/adapters/output/mailer/lettre/mod.rs
index 58abb85..f0e998b 100644
--- a/src/identity/adapters/output/mailer/lettre/mod.rs
+++ b/src/identity/adapters/output/mailer/lettre/mod.rs
@@ -2,10 +2,12 @@
 //
 // SPDX-License-Identifier: AGPL-3.0-or-later
 
-use lettre::{transport::smtp::authentication::Credentials, AsyncSmtpTransport, Tokio1Executor};
+use lettre::{AsyncSmtpTransport, Tokio1Executor};
 
 use crate::settings::Settings;
 
+pub mod account_validation_link;
+
 #[derive(Clone)]
 pub struct LettreMailer {
     mailer: AsyncSmtpTransport<Tokio1Executor>,
@@ -15,18 +17,17 @@ pub struct LettreMailer {
 
 impl LettreMailer {
     pub async fn new(s: &Settings) -> Self {
-        let creds = Credentials::new(s.email.username.clone(), s.email.password.clone());
-
         let mailer: AsyncSmtpTransport<Tokio1Executor> =
-            AsyncSmtpTransport::<Tokio1Executor>::relay(&s.email.server_hostname)
+            AsyncSmtpTransport::<Tokio1Executor>::from_url(s.email.url.as_str())
                 .unwrap()
-                .credentials(creds)
                 .build();
 
+        assert!(mailer.test_connection().await.unwrap());
+
         Self {
             mailer,
-            from: String::default(), // TODO: create settings module to read config
-            reply_to: String::default(),
+            from: s.email.from.clone(),
+            reply_to: s.email.reply_to.clone(),
         }
     }
 }