diff --git a/.fluence/aqua/services.aqua b/.fluence/aqua/services.aqua
index 87b80ab..572e3b5 100644
--- a/.fluence/aqua/services.aqua
+++ b/.fluence/aqua/services.aqua
@@ -7,6 +7,7 @@ data ExecutionConfig:
   private_key: string
   ceramic_endpoint: string
   checkpointer_endpoint: string
+  attestation_issuer: string
   attestation_model_id: string
   materialization_model_id: string
 
diff --git a/Cargo.toml b/Cargo.toml
index 630c6dd..bd01590 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -13,7 +13,6 @@ members = [
   anyhow = "1.0.80"
   async-trait = "0.1.77"
   base64 = "0.21.7"
-  clap = { version = "=4.4.18", default-features = false, features = ["derive", "std"] }
   curve25519-dalek = "=4.1.1"
   hmac = "0.12.1"
   jwt = "0.16.0"
@@ -25,6 +24,11 @@ members = [
   tracing-appender = "0.2.3"
   url = "2.5.0"
 
+    [workspace.dependencies.clap]
+    version = "=4.4.18"
+    default-features = false
+    features = [ "derive", "std" ]
+
     [workspace.dependencies.chrono]
     version = "0.4.34"
     features = [ "serde" ]
diff --git a/calculator/src/calculator.rs b/calculator/src/calculator.rs
index 0ae0c67..f943cb9 100644
--- a/calculator/src/calculator.rs
+++ b/calculator/src/calculator.rs
@@ -10,6 +10,7 @@ use std::str::FromStr;
 
 #[derive(Clone, Debug)]
 pub struct CalculatorParameters {
+    pub attestation_issuer: DidDocument,
     pub attestation_model_id: StreamId,
     pub materialization_model_id: StreamId,
 }
@@ -23,7 +24,12 @@ impl CalculatorParameters {
             std::env::var("MATERIALIZATION_MODEL_ID").unwrap_or_else(|_| {
                 "kjzl6hvfrbw6c88slfzg2mw6jvin2hgv2v24tbl9u0xc97f4pr4755xjr2l6sck".to_string()
             });
+        let attestation_issuer =
+            DidDocument::new(&std::env::var("ATTESTATION_ISSUER").unwrap_or_else(|_| {
+                "did:key:z6MkhER5181mt9PBCrnVvL9AcdWyzSzj4PLgGVKSFjJ8obMN".to_string()
+            }));
         Ok(Self {
+            attestation_issuer,
             attestation_model_id: StreamId::from_str(&attestation_model_id)?,
             materialization_model_id: StreamId::from_str(&materialization_model_id)?,
         })
@@ -56,9 +62,16 @@ impl Calculator {
         let attestation_stream_id = StreamId::from_str(&event.commit_id)?;
         match serde_json::from_str::<PointAttestations>(&event.content) {
             Ok(attestation) => {
+                if attestation.issuer != self.params.attestation_issuer.id {
+                    tracing::warn!(
+                        "Attestation issuer {} does not match expected {}",
+                        attestation.issuer,
+                        self.params.attestation_issuer.id
+                    );
+                    return Ok(());
+                }
                 if let Err(e) = validate_attestation(&attestation).await {
                     tracing::warn!("Error validating attestation: {}", e);
-                    return Ok(());
                 }
                 unique_events(
                     &mut self.cache,
diff --git a/fluence.yaml b/fluence.yaml
index 6ad33f6..6c14dbd 100644
--- a/fluence.yaml
+++ b/fluence.yaml
@@ -9,8 +9,8 @@ version: 8
 deployments:
   myDeployment:
     targetWorkers: 1
-    pricePerWorkerEpoch: 0.00001
-    initialBalance: 0.001
+    pricePerWorkerEpoch: "0.00001"
+    initialBalance: "0.001"
     services: [ event_joiner ]
     spells: [ event_joiner_periodic ]
 
diff --git a/fluence/src/services/event_joiner/modules/event_joiner/src/main.rs b/fluence/src/services/event_joiner/modules/event_joiner/src/main.rs
index cca2969..89db2c3 100644
--- a/fluence/src/services/event_joiner/modules/event_joiner/src/main.rs
+++ b/fluence/src/services/event_joiner/modules/event_joiner/src/main.rs
@@ -26,6 +26,7 @@ pub struct ExecutionConfig {
     pub private_key: String,
     pub ceramic_endpoint: String,
     pub checkpointer_endpoint: String,
+    pub attestation_issuer: String,
     pub attestation_model_id: String,
     pub materialization_model_id: String,
 }
@@ -64,12 +65,14 @@ async fn try_process_events(cfg: ExecutionConfig) -> Result<SseResponse, anyhow:
     let client_id = cfg.client_id;
     let attestation_model_id = StreamId::from_str(&cfg.attestation_model_id)?;
     let materialization_model_id = StreamId::from_str(&cfg.materialization_model_id)?;
+    let attestation_issuer = DidDocument::new(&cfg.attestation_issuer);
 
     let did = DidDocument::new(&cfg.public_key);
     let ceramic: Box<dyn calculator::Ceramic + Send + Sync> =
         Box::new(Ceramic::new(did.clone(), &cfg.private_key, ceramic_endpoint).await?);
     let mut calculator = calculator::Calculator::new(
         calculator::CalculatorParameters {
+            attestation_issuer,
             attestation_model_id,
             materialization_model_id,
         },
diff --git a/fluence/src/spells/event_joiner_periodic/spell.aqua b/fluence/src/spells/event_joiner_periodic/spell.aqua
index 0a95193..9df4c68 100644
--- a/fluence/src/spells/event_joiner_periodic/spell.aqua
+++ b/fluence/src/spells/event_joiner_periodic/spell.aqua
@@ -12,6 +12,7 @@ func spell():
       private_key = "pk",
       ceramic_endpoint = "http://localhost:7007",
       checkpointer_endpoint = "http://localhost:8080",
+      attestation_issuer = "did:key:z6MkhER5181mt9PBCrnVvL9AcdWyzSzj4PLgGVKSFjJ8obMN",
       attestation_model_id = "kjz",
       materialization_model_id = "kjz"
     ))