diff --git a/src/cloud_provider/aws/kubernetes/mod.rs b/src/cloud_provider/aws/kubernetes/mod.rs
index 4e588754..ef6b0ca7 100644
--- a/src/cloud_provider/aws/kubernetes/mod.rs
+++ b/src/cloud_provider/aws/kubernetes/mod.rs
@@ -138,15 +138,12 @@ impl<'a> Eks<'a> {
         let template_directory = format!("{}/aws/bootstrap", context.lib_root_dir());
 
         for node_group in &nodes_groups {
-            if AwsInstancesType::from_str(node_group.instance_type.as_str()).is_err() {
+            if let Err(e) = AwsInstancesType::from_str(node_group.instance_type.as_str()) {
                 return Err(EngineError::new(
                     EngineErrorCause::Internal,
                     EngineErrorScope::Engine,
                     context.execution_id(),
-                    Some(format!(
-                        "Nodegroup instance type {} is not valid for {}",
-                        node_group.instance_type, cloud_provider.name
-                    )),
+                    e.message,
                 ));
             }
         }
diff --git a/src/cloud_provider/aws/kubernetes/node.rs b/src/cloud_provider/aws/kubernetes/node.rs
index 41ad93a1..5626ccac 100644
--- a/src/cloud_provider/aws/kubernetes/node.rs
+++ b/src/cloud_provider/aws/kubernetes/node.rs
@@ -1,4 +1,5 @@
 use crate::cloud_provider::kubernetes::InstanceType;
+use crate::error::{SimpleError, SimpleErrorKind};
 use core::fmt;
 use serde::{Deserialize, Serialize};
 use std::str::FromStr;
@@ -54,9 +55,9 @@ impl fmt::Display for AwsInstancesType {
 }
 
 impl FromStr for AwsInstancesType {
-    type Err = ();
+    type Err = SimpleError;
 
-    fn from_str(s: &str) -> Result<AwsInstancesType, ()> {
+    fn from_str(s: &str) -> Result<AwsInstancesType, SimpleError> {
         match s {
             "t2.large" => Ok(AwsInstancesType::T2Large),
             "t2x.large" => Ok(AwsInstancesType::T2Xlarge),
@@ -64,7 +65,10 @@ impl FromStr for AwsInstancesType {
             "t3x.large" => Ok(AwsInstancesType::T3Xlarge),
             "t3a.large" => Ok(AwsInstancesType::T3aLarge),
             "t3a.2xlarge" => Ok(AwsInstancesType::T3a2xlarge),
-            _ => Err(()),
+            _ => Err(SimpleError::new(
+                SimpleErrorKind::Other,
+                Some(format!("Nodegroup instance type `{}` is not a valid for AWS", s)),
+            )),
         }
     }
 }
diff --git a/src/cloud_provider/digitalocean/kubernetes/mod.rs b/src/cloud_provider/digitalocean/kubernetes/mod.rs
index fd89b992..1a3d3bd4 100644
--- a/src/cloud_provider/digitalocean/kubernetes/mod.rs
+++ b/src/cloud_provider/digitalocean/kubernetes/mod.rs
@@ -106,15 +106,12 @@ impl<'a> DoKs<'a> {
         let template_directory = format!("{}/digitalocean/bootstrap", context.lib_root_dir());
 
         for node_group in &nodes_groups {
-            if DoInstancesType::from_str(node_group.instance_type.as_str()).is_err() {
+            if let Err(e) = DoInstancesType::from_str(node_group.instance_type.as_str()) {
                 return Err(EngineError::new(
                     EngineErrorCause::Internal,
                     EngineErrorScope::Engine,
                     context.execution_id(),
-                    Some(format!(
-                        "Nodegroup instance type {} is not valid for {}",
-                        node_group.instance_type, cloud_provider.name
-                    )),
+                    e.message,
                 ));
             }
         }
@@ -420,7 +417,7 @@ impl<'a> DoKs<'a> {
         let api_url = format!("{}/clusters", DoApiType::Doks.api_url());
         let json_content = do_get_from_api(self.cloud_provider.token.as_str(), DoApiType::Doks, api_url)?;
         // TODO(benjaminch): `qovery-` to be added into Rust name directly everywhere
-        get_doks_info_from_name(json_content.as_str(), format!("qovery-{}", self.id().to_string()))
+        get_doks_info_from_name(json_content.as_str(), format!("qovery-{}", self.id()))
     }
 }
 
diff --git a/src/cloud_provider/digitalocean/kubernetes/node.rs b/src/cloud_provider/digitalocean/kubernetes/node.rs
index 0d2b04a4..14ee7953 100644
--- a/src/cloud_provider/digitalocean/kubernetes/node.rs
+++ b/src/cloud_provider/digitalocean/kubernetes/node.rs
@@ -1,4 +1,5 @@
 use crate::cloud_provider::kubernetes::InstanceType;
+use crate::error::{SimpleError, SimpleErrorKind};
 use core::fmt;
 use serde::{Deserialize, Serialize};
 use std::str::FromStr;
@@ -58,9 +59,9 @@ impl fmt::Display for DoInstancesType {
 }
 
 impl FromStr for DoInstancesType {
-    type Err = ();
+    type Err = SimpleError;
 
-    fn from_str(s: &str) -> Result<DoInstancesType, ()> {
+    fn from_str(s: &str) -> Result<DoInstancesType, SimpleError> {
         match s {
             "s-1vcpu-1gb" => Ok(DoInstancesType::S1vcpu1gb),
             "s-1vcpu-2gb" => Ok(DoInstancesType::S1vcpu2gb),
@@ -69,7 +70,13 @@ impl FromStr for DoInstancesType {
             "s-4vcpu-8gb" => Ok(DoInstancesType::S4vcpu8gb),
             "s-6vcpu-16gb" => Ok(DoInstancesType::S6vcpu16gb),
             "s-8vcpu-32gb" => Ok(DoInstancesType::S8vcpu32gb),
-            _ => Err(()),
+            _ => Err(SimpleError::new(
+                SimpleErrorKind::Other,
+                Some(format!(
+                    "Nodegroup instance type `{}` is not a valid for DigitalOcean",
+                    s
+                )),
+            )),
         }
     }
 }
diff --git a/src/cloud_provider/kubernetes.rs b/src/cloud_provider/kubernetes.rs
index 2f810e28..157eae44 100644
--- a/src/cloud_provider/kubernetes.rs
+++ b/src/cloud_provider/kubernetes.rs
@@ -606,7 +606,7 @@ where
                 let error_message = format!(
                     "Wasn't able to delete all objects type {}, it's a blocker to then delete cert-manager namespace. {}",
                     object,
-                    format!("{:?}", msg)
+                    msg,
                 );
                 return Err(SimpleError::new(Other, Some(error_message)));
             }
diff --git a/src/cloud_provider/scaleway/kubernetes/mod.rs b/src/cloud_provider/scaleway/kubernetes/mod.rs
index 3340f449..5c3156b1 100644
--- a/src/cloud_provider/scaleway/kubernetes/mod.rs
+++ b/src/cloud_provider/scaleway/kubernetes/mod.rs
@@ -134,15 +134,12 @@ impl<'a> Kapsule<'a> {
         let template_directory = format!("{}/scaleway/bootstrap", context.lib_root_dir());
 
         for node_group in &nodes_groups {
-            if ScwInstancesType::from_str(node_group.instance_type.as_str()).is_err() {
+            if let Err(e) = ScwInstancesType::from_str(node_group.instance_type.as_str()) {
                 return Err(EngineError::new(
                     EngineErrorCause::Internal,
                     EngineErrorScope::Engine,
                     context.execution_id(),
-                    Some(format!(
-                        "Nodegroup instance type {} is not valid for {}",
-                        node_group.instance_type, cloud_provider.name
-                    )),
+                    e.message,
                 ));
             }
         }
diff --git a/src/cloud_provider/scaleway/kubernetes/node.rs b/src/cloud_provider/scaleway/kubernetes/node.rs
index f94382f1..54b2205c 100644
--- a/src/cloud_provider/scaleway/kubernetes/node.rs
+++ b/src/cloud_provider/scaleway/kubernetes/node.rs
@@ -1,4 +1,5 @@
 use crate::cloud_provider::kubernetes::InstanceType;
+use crate::error::{SimpleError, SimpleErrorKind};
 use serde::{Deserialize, Serialize};
 use std::fmt;
 use std::str::FromStr;
@@ -66,9 +67,9 @@ impl fmt::Display for ScwInstancesType {
 }
 
 impl FromStr for ScwInstancesType {
-    type Err = ();
+    type Err = SimpleError;
 
-    fn from_str(s: &str) -> Result<ScwInstancesType, ()> {
+    fn from_str(s: &str) -> Result<ScwInstancesType, SimpleError> {
         match s {
             "gp1-xs" => Ok(ScwInstancesType::Gp1Xs),
             "gp1-s" => Ok(ScwInstancesType::Gp1S),
@@ -79,7 +80,10 @@ impl FromStr for ScwInstancesType {
             "dev1-l" => Ok(ScwInstancesType::Dev1L),
             "dev1-xl" => Ok(ScwInstancesType::Dev1Xl),
             "render-s" => Ok(ScwInstancesType::RenderS),
-            _ => Err(()),
+            _ => Err(SimpleError::new(
+                SimpleErrorKind::Other,
+                Some(format!("Nodegroup instance type `{}` is not a valid for Scaleway", s)),
+            )),
         }
     }
 }
diff --git a/src/cloud_provider/utilities.rs b/src/cloud_provider/utilities.rs
index 8bfa7941..bd53cfb2 100644
--- a/src/cloud_provider/utilities.rs
+++ b/src/cloud_provider/utilities.rs
@@ -166,10 +166,7 @@ pub fn generate_supported_version(
 
             if minor_min == minor_max {
                 // add short minor format targeting latest version
-                supported_versions.insert(
-                    format!("{}.{}", major.to_string(), minor_max.to_string()),
-                    latest_major_version.clone(),
-                );
+                supported_versions.insert(format!("{}.{}", major, minor_max), latest_major_version.clone());
                 if update_min.unwrap() == update_max.unwrap() {
                     let version = format!("{}.{}.{}", major, minor_min, update_min.unwrap());
                     supported_versions.insert(version.clone(), format!("{}{}", version, suffix));
@@ -183,13 +180,8 @@ pub fn generate_supported_version(
                 for minor in minor_min..minor_max + 1 {
                     // add short minor format targeting latest version
                     supported_versions.insert(
-                        format!("{}.{}", major.to_string(), minor.to_string()),
-                        format!(
-                            "{}.{}.{}",
-                            major.to_string(),
-                            minor.to_string(),
-                            update_max.unwrap().to_string()
-                        ),
+                        format!("{}.{}", major, minor),
+                        format!("{}.{}.{}", major, minor, update_max.unwrap(),),
                     );
                     if update_min.unwrap() == update_max.unwrap() {
                         let version = format!("{}.{}.{}", major, minor, update_min.unwrap());
diff --git a/src/container_registry/aws_ecr.rs b/src/container_registry/aws_ecr.rs
index 96dad923..3f27ae61 100644
--- a/src/container_registry/aws_ecr.rs
+++ b/src/container_registry/aws_ecr.rs
@@ -387,7 +387,7 @@ impl ContainerRegistry for AwsEcr {
             }
         };
 
-        if cmd::utilities::exec(
+        if let Err(e) = cmd::utilities::exec(
             "docker",
             vec![
                 "login",
@@ -398,15 +398,17 @@ impl ContainerRegistry for AwsEcr {
                 endpoint_url.as_str(),
             ],
             &self.docker_envs(),
-        )
-        .is_err()
-        {
+        ) {
             return Err(self.engine_error(
                 EngineErrorCause::User(
                     "Your ECR account seems to be no longer valid (bad Credentials). \
                 Please contact your Organization administrator to fix or change the Credentials.",
                 ),
-                format!("failed to login to ECR {}", self.name_with_id()),
+                format!(
+                    "failed to login to ECR {}, error: {}",
+                    self.name_with_id(),
+                    e.message.unwrap_or_else(|| "no error message".to_string())
+                ),
             ));
         };
 
diff --git a/src/container_registry/digitalocean_container_registry.rs b/src/container_registry/digitalocean_container_registry.rs
index 78cae83a..aa58799c 100644
--- a/src/container_registry/digitalocean_container_registry.rs
+++ b/src/container_registry/digitalocean_container_registry.rs
@@ -312,19 +312,21 @@ impl ContainerRegistry for DigitalOceanCr {
             Err(_) => warn!("DOCR {} already exists", registry_name.as_str()),
         };
 
-        if cmd::utilities::exec(
+        if let Err(e) = cmd::utilities::exec(
             "doctl",
             vec!["registry", "login", self.name.as_str(), "-t", self.api_key.as_str()],
             &[],
-        )
-        .is_err()
-        {
+        ) {
             return Err(self.engine_error(
                 EngineErrorCause::User(
                     "Your DOCR account seems to be no longer valid (bad Credentials). \
                     Please contact your Organization administrator to fix or change the Credentials.",
                 ),
-                format!("failed to login to DOCR {}", self.name_with_id()),
+                format!(
+                    "failed to login to DOCR {}, error: {}",
+                    self.name_with_id(),
+                    e.message.unwrap_or_else(|| "no error message".to_string())
+                ),
             ));
         };
 
diff --git a/src/container_registry/docker_hub.rs b/src/container_registry/docker_hub.rs
index 17d726ab..5e23f68a 100644
--- a/src/container_registry/docker_hub.rs
+++ b/src/container_registry/docker_hub.rs
@@ -113,19 +113,21 @@ impl ContainerRegistry for DockerHub {
             None => vec![],
         };
 
-        if cmd::utilities::exec(
+        if let Err(e) = cmd::utilities::exec(
             "docker",
             vec!["login", "-u", self.login.as_str(), "-p", self.password.as_str()],
             &envs,
-        )
-        .is_err()
-        {
+        ) {
             return Err(self.engine_error(
                 EngineErrorCause::User(
                     "Your DockerHub account seems to be no longer valid (bad Credentials). \
                 Please contact your Organization administrator to fix or change the Credentials.",
                 ),
-                format!("failed to login to DockerHub {}", self.name_with_id()),
+                format!(
+                    "failed to login to DockerHub {}, error: {}",
+                    self.name_with_id(),
+                    e.message.unwrap_or_else(|| "no error message".to_string())
+                ),
             ));
         };
 
diff --git a/src/container_registry/scaleway_container_registry.rs b/src/container_registry/scaleway_container_registry.rs
index 6246297b..4be51595 100644
--- a/src/container_registry/scaleway_container_registry.rs
+++ b/src/container_registry/scaleway_container_registry.rs
@@ -391,21 +391,23 @@ impl ContainerRegistry for ScalewayCr {
             }
         }
 
-        if docker_login(
+        if let Err(e) = docker_login(
             Kind::ScalewayCr,
             self.get_docker_envs(),
             self.login.clone(),
             self.secret_token.clone(),
             registry_url.clone(),
-        )
-        .is_err()
-        {
+        ) {
             return Err(self.engine_error(
                 EngineErrorCause::User(
                     "Your Scaleway account seems to be no longer valid (bad Credentials). \
                 Please contact your Organization administrator to fix or change the Credentials.",
                 ),
-                format!("failed to login to Scaleway {}", self.name_with_id()),
+                format!(
+                    "failed to login to Scaleway {}, error: {}",
+                    self.name_with_id(),
+                    e.message.unwrap_or_else(|| "no error message".to_string())
+                ),
             ));
         };
 
diff --git a/src/object_storage/scaleway_object_storage.rs b/src/object_storage/scaleway_object_storage.rs
index a6946e9b..1f835389 100644
--- a/src/object_storage/scaleway_object_storage.rs
+++ b/src/object_storage/scaleway_object_storage.rs
@@ -72,7 +72,7 @@ impl ScalewayOS {
     }
 
     fn get_endpoint_url_for_region(&self) -> String {
-        format!("https://s3.{}.scw.cloud", self.zone.region().to_string())
+        format!("https://s3.{}.scw.cloud", self.zone.region())
     }
 
     fn is_bucket_name_valid(bucket_name: &str) -> Result<(), Option<String>> {
diff --git a/tests/helpers/helpers_common.rs b/tests/helpers/helpers_common.rs
index 3676d119..2c6d19f6 100644
--- a/tests/helpers/helpers_common.rs
+++ b/tests/helpers/helpers_common.rs
@@ -21,9 +21,9 @@ pub fn environment_3_apps_3_routers_3_databases(
     database_instance_type: &str,
     database_disk_type: &str,
 ) -> Environment {
-    let app_name_1 = format!("{}-{}", "simple-app-1".to_string(), generate_id());
-    let app_name_2 = format!("{}-{}", "simple-app-2".to_string(), generate_id());
-    let app_name_3 = format!("{}-{}", "simple-app-3".to_string(), generate_id());
+    let app_name_1 = format!("{}-{}", "simple-app-1", generate_id());
+    let app_name_2 = format!("{}-{}", "simple-app-2", generate_id());
+    let app_name_3 = format!("{}-{}", "simple-app-3", generate_id());
 
     // mongoDB management part
     let database_host_mongo = format!("mongodb-{}.{}", generate_id(), &test_domain);
@@ -295,7 +295,7 @@ pub fn working_minimal_environment(context: &Context, organization_id: &str, tes
         action: Action::Create,
         applications: vec![Application {
             id: generate_id(),
-            name: format!("{}-{}", "simple-app".to_string(), &suffix),
+            name: format!("{}-{}", "simple-app", &suffix),
             git_url: "https://github.com/Qovery/engine-testing.git".to_string(),
             commit_id: "fc575a2f3be0b9100492c8a463bf18134a8698a5".to_string(),
             dockerfile_path: Some("Dockerfile".to_string()),
@@ -326,7 +326,7 @@ pub fn working_minimal_environment(context: &Context, organization_id: &str, tes
             custom_domains: vec![],
             routes: vec![Route {
                 path: "/".to_string(),
-                application_name: format!("{}-{}", "simple-app".to_string(), &suffix),
+                application_name: format!("{}-{}", "simple-app", &suffix),
             }],
         }],
         databases: vec![],
@@ -517,7 +517,7 @@ pub fn echo_app_environment(context: &Context, organization_id: &str, test_domai
         action: Action::Create,
         applications: vec![Application {
             id: generate_id(),
-            name: format!("{}-{}", "echo-app".to_string(), &suffix),
+            name: format!("{}-{}", "echo-app", &suffix),
             /*name: "simple-app".to_string(),*/
             git_url: "https://github.com/Qovery/engine-testing.git".to_string(),
             commit_id: "2205adea1db295547b99f7b17229afd7e879b6ff".to_string(),
@@ -551,7 +551,7 @@ pub fn echo_app_environment(context: &Context, organization_id: &str, test_domai
             custom_domains: vec![],
             routes: vec![Route {
                 path: "/".to_string(),
-                application_name: format!("{}-{}", "echo-app".to_string(), &suffix),
+                application_name: format!("{}-{}", "echo-app", &suffix),
             }],
         }],
         databases: vec![],
diff --git a/tests/helpers/utilities.rs b/tests/helpers/utilities.rs
index f43835b0..035df404 100644
--- a/tests/helpers/utilities.rs
+++ b/tests/helpers/utilities.rs
@@ -467,7 +467,7 @@ where
                 ));
 
                 if let Err(e) = clusters_res {
-                    let message = format!("error while trying to get clusters, error: {}", e.to_string());
+                    let message = format!("error while trying to get clusters, error: {}", e);
                     error!("{}", message);
 
                     return OperationResult::Retry(SimpleError::new(SimpleErrorKind::Other, Some(message.as_str())));
@@ -504,8 +504,7 @@ where
                                         );
                                     }
                                     Err(e) => {
-                                        let message =
-                                            format!("error while trying to get clusters, error: {}", e.to_string());
+                                        let message = format!("error while trying to get clusters, error: {}", e);
                                         error!("{}", message);
 
                                         return OperationResult::Retry(SimpleError::new(