diff --git a/src/clienthandler.rs b/src/clienthandler.rs
index dd9bcb0..43256e1 100644
--- a/src/clienthandler.rs
+++ b/src/clienthandler.rs
@@ -200,6 +200,7 @@ impl ClientHandler {
 				//We receive a result of a credential validation request or service registration from the credential gateway.
 				let mut receive_credential_events_handler_lock = self.receive_credential_events_handler.lock();
 				if let Ok(event) = receive_credential_events_handler_lock.await.try_recv() {
+					//TODO: if ServiceDeliveranceResult, flush out the internal buffer to store in our NoteProcessor
 					client_events.push(event);
 				}
 			}
@@ -392,6 +393,7 @@ impl ClientHandler {
 								self.filter_events(*msg).await;
 								//TODO: we should link our filtering policy to our db storing,
 								//otherwise this is a severe DoS vector
+								//TODO: move is_ephemeral check when receive result from CredentialGateway is in NoteProcessor
 								if !is_ephemeral(&msg_2) {
 									let db_request = DbRequest::WriteEvent(*msg_2);
 									write_db.push(db_request);
diff --git a/src/credentialgateway.rs b/src/credentialgateway.rs
index 223e8dc..5c14198 100644
--- a/src/credentialgateway.rs
+++ b/src/credentialgateway.rs
@@ -22,7 +22,9 @@ use nostr::{Event, Kind, Tag, TagKind};
 
 use staking_credentials::common::msgs::{AssetProofFeatures, CredentialsFeatures, CredentialPolicy, ServicePolicy};
 use staking_credentials::common::utils::Proof;
+
 use staking_credentials::issuance::issuerstate::IssuerState;
+use staking_credentials::redemption::redemption::RedemptionEngine;
 
 use staking_credentials::common::msgs::{CredentialAuthenticationResult, CredentialAuthenticationPayload, Decodable, ServiceDeliveranceResult, FromHex};
 use staking_credentials::common::utils::Credentials;
@@ -122,18 +124,24 @@ impl IssuanceManager {
 
 }
 
-struct RedemptionManager { }
+struct RedemptionManager {
+	redemption_engine: RedemptionEngine,
+}
 
 impl RedemptionManager {
-	fn validate_service_deliverance(&mut self, client_id: u64, ev: Event) -> Result<ServiceDeliveranceResult, ()> {
+	fn validate_service_deliverance(&mut self, client_id: u64, ev: Event) -> ServiceDeliveranceResult {
 
 		let service_id = 0;
 		let ret = false;
 		let reason = vec![];
 
+		//TODO: take a PubklicKey and a Credential and a Signature. Outcome a boolean.
+		//let valid = self.redemption_engine.verify_credentials();
+
 		let mut service_deliverance_result = ServiceDeliveranceResult::new(service_id, ret, reason);
 
-		Ok(service_deliverance_result)
+		// We always return a valid ServiceDeliveranceResult, all errors should be treated as invalid.
+		service_deliverance_result
 	}
 }
 
@@ -189,8 +197,10 @@ impl CredentialGateway {
 			issuance_engine: issuer_state,
 		};
 
-		let redemption_manager = RedemptionManager {
+		let redemption_engine = RedemptionEngine::new();
 
+		let redemption_manager = RedemptionManager {
+			redemption_engine,	
 		};
 
 		let hosted_services = HashMap::new();
@@ -237,25 +247,36 @@ impl CredentialGateway {
 			}
 
 			let mut proofs_to_verify = Vec::new();
+			let mut redemption_result = Vec::new();
 			//TODO: change serialization of credential message from bytes payload to encompass ServiceDelivereRequest.
 			//let mut deliverance_result_queue = Vec::new();
 			for event in credential_queue {
 				match event {
 					ClientEvents::Credential { client_id, event } => {
-						match event.tags[0].kind() {
+						// let credential_msg = event.decode_from_nostr();
+						let credential_type = 0; // credential_msg.get_credential_type();
+						match credential_type {
 							//TODO: decode and check the exact credential requested from client
-							TagKind::Credential => {
+							0 => {
 								match self.issuance_manager.register_authentication_request(client_id, event) {
 									Ok(proof) => {
 										println!("[CIVKITD] - CREDENTIAL: adding a merkle block proof to verify");
 										proofs_to_verify.push(proof);
 									},
 									Err(error) => {
-										println!("[CIVKITD] - CREDENTIAL: authentication request error {:?}", error); 
+										println!("[CIVKITD] - CREDENTIAL: authentication request error {:?}", error);
 									}
 								}
 							},
-							_ => { println!("[CIVKITD] - CREDENTIAL: credential event error: unknown kind"); }
+							1 => { println!("[CIVKITD] - CREDENTIAL event error: gateway should not receive CredentialAuthenticationResult"); },
+							3 => {
+								let result =  self.redemption_manager.validate_service_deliverance(client_id, event);
+								println!("[CIVKITD] - CREDENTIAL: service deliverance validation result {}", result.ret);
+								//TODO: build back Nostr event here ?
+								redemption_result.push(result);
+							},
+							4 => { println!("[CIVKITD] - CREDENTIAL event error: gateway should not receive ServiceDeliveranceResult"); },
+							_ => { println!("[CIVKITD] - CREDENTIAL: credential event error: unknown type"); }
 						}
 					},
 					_ => {},
@@ -268,7 +289,6 @@ impl CredentialGateway {
 				send_bitcoind_request_lock.await.send(BitcoindRequest::CheckMerkleProof { request_id, proof });
 			}
 
-
 			let mut validated_requests = Vec::new();
 			{
 				let mut receive_bitcoind_result_handler_lock = self.receive_bitcoind_result_handler.lock();
@@ -297,6 +317,13 @@ impl CredentialGateway {
 				}
 			}
 
+			{
+				for result in redemption_result {
+					let mut send_credential_lock = self.send_credential_events_gateway.lock();
+					//TODO: send back event 
+				}
+			}
+
 			let mut service_registration_request = Vec::new();
 			{
 				let mut receive_events_gateway_lock = self.receive_events_gateway.lock();
diff --git a/src/kindprocessor.rs b/src/kindprocessor.rs
index c4be9e6..285ef61 100644
--- a/src/kindprocessor.rs
+++ b/src/kindprocessor.rs
@@ -38,6 +38,8 @@ pub struct NoteProcessor {
 
 	receive_db_requests_manager: TokioMutex<mpsc::UnboundedReceiver<DbRequest>>,
 
+	//TODO: add buffer of pending write DB for each client.
+
 	config: Config,
 }
 
@@ -78,6 +80,8 @@ impl NoteProcessor {
 		loop {
 			sleep(Duration::from_millis(1000)).await;
 
+			//TODO: wait for the ServiceDeliveranceResult of the CredentialGateway before to trigger write_new_event_db.
+
 			let mut replay_request = Vec::new();
 			let mut ok_events = Vec::new();
 			{