diff --git a/crates/bioauth-flow-rpc/src/data.rs b/crates/bioauth-flow-rpc/src/data.rs
new file mode 100644
index 000000000..6108720a6
--- /dev/null
+++ b/crates/bioauth-flow-rpc/src/data.rs
@@ -0,0 +1,48 @@
+//! The RPC request and response data, excluding errors.
+
+/// The parameters necessary to initialize the FaceTec Device SDK.
+pub type FacetecDeviceSdkParams = serde_json::Map<String, serde_json::Value>;
+
+/// The bioauth status as used in the RPC.
+#[derive(Debug, PartialEq, Eq, serde::Serialize, serde::Deserialize)]
+pub enum BioauthStatus<Timestamp> {
+    /// When the status can't be determined, but there was no error.
+    /// Can happen if the validator key is absent.
+    Unknown,
+    /// There is no active authentication for the currently used validator key.
+    Inactive,
+    /// There is an active authentication for the currently used validator key.
+    Active {
+        /// The timestamp when the authentication will expire.
+        expires_at: Timestamp,
+    },
+}
+
+impl<T> From<bioauth_flow_api::BioauthStatus<T>> for BioauthStatus<T> {
+    fn from(status: bioauth_flow_api::BioauthStatus<T>) -> Self {
+        match status {
+            bioauth_flow_api::BioauthStatus::Inactive => Self::Inactive,
+            bioauth_flow_api::BioauthStatus::Active { expires_at } => Self::Active { expires_at },
+        }
+    }
+}
+
+/// `enroll_v2` flow result.
+#[derive(Debug, PartialEq, Eq, serde::Serialize, serde::Deserialize)]
+#[serde(rename_all = "camelCase")]
+pub struct EnrollV2Result {
+    /// Scan result blob.
+    pub scan_result_blob: Option<String>,
+}
+
+/// `authenticate_v2` related flow result.
+#[derive(Debug, PartialEq, Eq, serde::Serialize, serde::Deserialize)]
+#[serde(rename_all = "camelCase")]
+pub struct AuthenticateV2Result {
+    /// An opaque auth ticket generated for this authentication attempt.
+    pub auth_ticket: Box<[u8]>,
+    /// The robonode signature for this opaque auth ticket.
+    pub auth_ticket_signature: Box<[u8]>,
+    /// Scan result blob.
+    pub scan_result_blob: Option<String>,
+}
diff --git a/crates/bioauth-flow-rpc/src/error/code.rs b/crates/bioauth-flow-rpc/src/error/code.rs
new file mode 100644
index 000000000..83a2483c2
--- /dev/null
+++ b/crates/bioauth-flow-rpc/src/error/code.rs
@@ -0,0 +1,21 @@
+//! Custom rpc error codes.
+
+/// Signer has failed.
+pub const SIGN: i32 = 100;
+
+/// Request to robonode has failed.
+pub const ROBONODE: i32 = 200;
+
+/// Call to runtime api has failed.
+pub const RUNTIME_API: i32 = 300;
+
+/// Authenticate transaction has failed.
+pub const TRANSACTION: i32 = 400;
+
+/// Validator key is not available.
+pub const MISSING_VALIDATOR_KEY: i32 =
+    rpc_validator_key_logic::api_error_code::MISSING_VALIDATOR_KEY;
+
+/// Validator key extraction has failed.
+pub const VALIDATOR_KEY_EXTRACTION: i32 =
+    rpc_validator_key_logic::api_error_code::VALIDATOR_KEY_EXTRACTION;
diff --git a/crates/bioauth-flow-rpc/src/error_data.rs b/crates/bioauth-flow-rpc/src/error/data.rs
similarity index 100%
rename from crates/bioauth-flow-rpc/src/error_data.rs
rename to crates/bioauth-flow-rpc/src/error/data.rs
diff --git a/crates/bioauth-flow-rpc/src/error/mod.rs b/crates/bioauth-flow-rpc/src/error/mod.rs
new file mode 100644
index 000000000..c20ba46ab
--- /dev/null
+++ b/crates/bioauth-flow-rpc/src/error/mod.rs
@@ -0,0 +1,8 @@
+//! All bioauth flow error kinds that we expose in the RPC.
+
+pub mod code;
+pub mod data;
+pub mod shared;
+mod sign;
+
+pub use self::sign::Error as Sign;
diff --git a/crates/bioauth-flow-rpc/src/errors/shared.rs b/crates/bioauth-flow-rpc/src/error/shared.rs
similarity index 73%
rename from crates/bioauth-flow-rpc/src/errors/shared.rs
rename to crates/bioauth-flow-rpc/src/error/shared.rs
index 7f3493744..c8b8aa0ea 100644
--- a/crates/bioauth-flow-rpc/src/errors/shared.rs
+++ b/crates/bioauth-flow-rpc/src/error/shared.rs
@@ -3,7 +3,7 @@
 use rpc_validator_key_logic::Error as ValidatorKeyError;
 use serde::Serialize;
 
-use super::{api_error_code, sign::Error as SignError};
+use super::{code, sign::Error as SignError};
 
 /// The robonode requests related error.
 #[derive(Debug)]
@@ -28,24 +28,21 @@ impl<T: std::error::Error + 'static> FlowBaseError<T> {
         match self {
             Self::KeyExtraction(err @ ValidatorKeyError::MissingValidatorKey) => {
                 rpc_error_response::data(
-                    api_error_code::MISSING_VALIDATOR_KEY,
+                    code::MISSING_VALIDATOR_KEY,
                     err.to_string(),
                     rpc_validator_key_logic::error_data::ValidatorKeyNotAvailable,
                 )
             }
             Self::KeyExtraction(err @ ValidatorKeyError::ValidatorKeyExtraction) => {
-                rpc_error_response::simple(
-                    api_error_code::VALIDATOR_KEY_EXTRACTION,
-                    err.to_string(),
-                )
+                rpc_error_response::simple(code::VALIDATOR_KEY_EXTRACTION, err.to_string())
             }
-            Self::Sign(err) => rpc_error_response::simple(api_error_code::SIGN, err.to_string()),
+            Self::Sign(err) => rpc_error_response::simple(code::SIGN, err.to_string()),
             Self::RobonodeClient(err @ robonode_client::Error::Call(inner)) => {
                 let maybe_data = (robonode_call_error_data)(inner);
-                rpc_error_response::raw(api_error_code::ROBONODE, err.to_string(), maybe_data)
+                rpc_error_response::raw(code::ROBONODE, err.to_string(), maybe_data)
             }
             Self::RobonodeClient(err @ robonode_client::Error::Reqwest(_)) => {
-                rpc_error_response::simple(api_error_code::ROBONODE, err.to_string())
+                rpc_error_response::simple(code::ROBONODE, err.to_string())
             }
         }
     }
diff --git a/crates/bioauth-flow-rpc/src/errors/sign.rs b/crates/bioauth-flow-rpc/src/error/sign.rs
similarity index 100%
rename from crates/bioauth-flow-rpc/src/errors/sign.rs
rename to crates/bioauth-flow-rpc/src/error/sign.rs
diff --git a/crates/bioauth-flow-rpc/src/errors/mod.rs b/crates/bioauth-flow-rpc/src/errors/mod.rs
deleted file mode 100644
index 0d5014562..000000000
--- a/crates/bioauth-flow-rpc/src/errors/mod.rs
+++ /dev/null
@@ -1,34 +0,0 @@
-//! All bioauth flow error kinds that we expose in the RPC.
-
-pub mod authenticate;
-pub mod authenticate_v2;
-pub mod enroll;
-pub mod enroll_v2;
-pub mod get_facetec_device_sdk_params;
-pub mod get_facetec_session_token;
-pub mod shared;
-pub mod sign;
-pub mod status;
-
-/// Custom rpc error codes.
-pub mod api_error_code {
-    /// Signer has failed.
-    pub const SIGN: i32 = 100;
-
-    /// Request to robonode has failed.
-    pub const ROBONODE: i32 = 200;
-
-    /// Call to runtime api has failed.
-    pub const RUNTIME_API: i32 = 300;
-
-    /// Authenticate transaction has failed.
-    pub const TRANSACTION: i32 = 400;
-
-    /// Validator key is not available.
-    pub const MISSING_VALIDATOR_KEY: i32 =
-        rpc_validator_key_logic::api_error_code::MISSING_VALIDATOR_KEY;
-
-    /// Validator key extraction has failed.
-    pub const VALIDATOR_KEY_EXTRACTION: i32 =
-        rpc_validator_key_logic::api_error_code::VALIDATOR_KEY_EXTRACTION;
-}
diff --git a/crates/bioauth-flow-rpc/src/lib.rs b/crates/bioauth-flow-rpc/src/lib.rs
index 6ee994da0..6db02510d 100644
--- a/crates/bioauth-flow-rpc/src/lib.rs
+++ b/crates/bioauth-flow-rpc/src/lib.rs
@@ -9,96 +9,29 @@ use std::sync::Arc;
 
 use bioauth_flow_api::BioauthFlowApi;
 use bioauth_keys::traits::KeyExtractor as KeyExtractorT;
-use errors::{
-    authenticate::Error as AuthenticateError, authenticate_v2::Error as AuthenticateV2Error,
-    enroll::Error as EnrollError, enroll_v2::Error as EnrollV2Error,
-    get_facetec_device_sdk_params::Error as GetFacetecDeviceSdkParamsError,
-    get_facetec_session_token::Error as GetFacetecSessionToken, shared::FlowBaseError,
-    sign::Error as SignError, status::Error as StatusError,
-};
 use futures::StreamExt;
 use jsonrpsee::{core::RpcResult, proc_macros::rpc};
 use primitives_liveness_data::{LivenessData, OpaqueLivenessData};
 use robonode_client::{AuthenticateRequest, AuthenticateResponse, EnrollRequest, EnrollResponse};
 use rpc_deny_unsafe::DenyUnsafe;
 use sc_transaction_pool_api::{TransactionPool as TransactionPoolT, TransactionStatus, TxHash};
-use serde::{Deserialize, Serialize};
-use serde_json::{Map, Value};
 use sp_api::{BlockT, Decode, Encode, ProvideRuntimeApi};
 use sp_blockchain::HeaderBackend;
 use tracing::*;
 
-pub mod error_data;
-mod errors;
+pub mod data;
+pub mod error;
+pub mod method;
+pub mod signer;
 
-/// Signer provides signatures for the data.
-#[async_trait::async_trait]
-pub trait Signer<S> {
-    /// Signature error.
-    /// Error may originate from communicating with HSM, or from a thread pool failure, etc.
-    type Error;
-
-    /// Sign the provided data and return the signature, or an error if the signing fails.
-    async fn sign<'a, D>(&self, data: D) -> std::result::Result<S, Self::Error>
-    where
-        D: AsRef<[u8]> + Send + 'a;
-}
-
-/// A factory that spits out [`Signer`]s.
-pub trait SignerFactory<S, K> {
-    /// The type of [`Signer`] this factory will create.
-    type Signer: Signer<S>;
-
-    /// Create a [`Signer`] using the provided public key.
-    fn new_signer(&self, key: K) -> Self::Signer;
-}
-
-impl<S, T, F, K, P> SignerFactory<T, K> for P
-where
-    P: std::ops::Deref<Target = F>,
-    F: Fn(K) -> S,
-    S: Signer<T>,
-{
-    type Signer = S;
-
-    fn new_signer(&self, key: K) -> Self::Signer {
-        self(key)
-    }
-}
-
-/// The parameters necessary to initialize the FaceTec Device SDK.
-type FacetecDeviceSdkParams = Map<String, Value>;
-
-/// The bioauth status as used in the RPC.
-#[derive(Debug, PartialEq, Eq, Serialize, Deserialize)]
-pub enum BioauthStatus<Timestamp> {
-    /// When the status can't be determined, but there was no error.
-    /// Can happen if the validator key is absent.
-    Unknown,
-    /// There is no active authentication for the currently used validator key.
-    Inactive,
-    /// There is an active authentication for the currently used validator key.
-    Active {
-        /// The timestamp when the authentication will expire.
-        expires_at: Timestamp,
-    },
-}
-
-impl<T> From<bioauth_flow_api::BioauthStatus<T>> for BioauthStatus<T> {
-    fn from(status: bioauth_flow_api::BioauthStatus<T>) -> Self {
-        match status {
-            bioauth_flow_api::BioauthStatus::Inactive => Self::Inactive,
-            bioauth_flow_api::BioauthStatus::Active { expires_at } => Self::Active { expires_at },
-        }
-    }
-}
+pub use self::signer::Signer;
 
 /// The API exposed via JSON-RPC.
 #[rpc(server)]
 pub trait Bioauth<Timestamp, TxHash> {
     /// Get the configuration required for the Device SDK.
     #[method(name = "bioauth_getFacetecDeviceSdkParams")]
-    async fn get_facetec_device_sdk_params(&self) -> RpcResult<FacetecDeviceSdkParams>;
+    async fn get_facetec_device_sdk_params(&self) -> RpcResult<data::FacetecDeviceSdkParams>;
 
     /// Get a FaceTec Session Token.
     #[method(name = "bioauth_getFacetecSessionToken")]
@@ -106,7 +39,7 @@ pub trait Bioauth<Timestamp, TxHash> {
 
     /// Get the current bioauth status.
     #[method(name = "bioauth_status")]
-    async fn status(&self) -> RpcResult<BioauthStatus<Timestamp>>;
+    async fn status(&self) -> RpcResult<data::BioauthStatus<Timestamp>>;
 
     /// Enroll with provided liveness data.
     #[method(name = "bioauth_enroll")]
@@ -114,7 +47,7 @@ pub trait Bioauth<Timestamp, TxHash> {
 
     /// Enroll with provided liveness data V2.
     #[method(name = "bioauth_enrollV2")]
-    async fn enroll_v2(&self, liveness_data: LivenessData) -> RpcResult<EnrollV2Result>;
+    async fn enroll_v2(&self, liveness_data: LivenessData) -> RpcResult<data::EnrollV2Result>;
 
     /// Authenticate with provided liveness data.
     #[method(name = "bioauth_authenticate")]
@@ -122,28 +55,10 @@ pub trait Bioauth<Timestamp, TxHash> {
 
     /// Request auth ticket based on provided liveness data.
     #[method(name = "bioauth_authenticateV2")]
-    async fn authenticate_v2(&self, liveness_data: LivenessData)
-        -> RpcResult<AuthenticateV2Result>;
-}
-
-/// `enroll_v2` flow result.
-#[derive(Debug, PartialEq, Eq, Serialize, Deserialize)]
-#[serde(rename_all = "camelCase")]
-pub struct EnrollV2Result {
-    /// Scan result blob.
-    pub scan_result_blob: Option<String>,
-}
-
-/// `authenticate_v2` related flow result.
-#[derive(Debug, PartialEq, Eq, Serialize, Deserialize)]
-#[serde(rename_all = "camelCase")]
-pub struct AuthenticateV2Result {
-    /// An opaque auth ticket generated for this authentication attempt.
-    pub auth_ticket: Box<[u8]>,
-    /// The robonode signature for this opaque auth ticket.
-    pub auth_ticket_signature: Box<[u8]>,
-    /// Scan result blob.
-    pub scan_result_blob: Option<String>,
+    async fn authenticate_v2(
+        &self,
+        liveness_data: LivenessData,
+    ) -> RpcResult<data::AuthenticateV2Result>;
 }
 
 /// The RPC implementation.
@@ -235,20 +150,20 @@ where
     ValidatorKeyExtractor: KeyExtractorT,
     ValidatorKeyExtractor::PublicKeyType: Encode + AsRef<[u8]> + Clone,
     ValidatorKeyExtractor::Error: std::fmt::Debug,
-    ValidatorSignerFactory: SignerFactory<Vec<u8>, ValidatorKeyExtractor::PublicKeyType>,
-    <<ValidatorSignerFactory as SignerFactory<Vec<u8>, ValidatorKeyExtractor::PublicKeyType>>::Signer as Signer<Vec<u8>>>::Error:
+    ValidatorSignerFactory: signer::Factory<Vec<u8>, ValidatorKeyExtractor::PublicKeyType>,
+    <<ValidatorSignerFactory as signer::Factory<Vec<u8>, ValidatorKeyExtractor::PublicKeyType>>::Signer as Signer<Vec<u8>>>::Error:
         std::error::Error + 'static,
     Block: BlockT,
     TransactionPool: TransactionPoolT<Block = Block>,
 {
     /// Return the opaque liveness data and corresponding signature.
-    async fn sign(&self, validator_key: <ValidatorKeyExtractor as KeyExtractorT>::PublicKeyType, liveness_data: &LivenessData) -> Result<(OpaqueLivenessData, Vec<u8>), SignError> {
+    async fn sign(&self, validator_key: <ValidatorKeyExtractor as KeyExtractorT>::PublicKeyType, liveness_data: &LivenessData) -> Result<(OpaqueLivenessData, Vec<u8>), error::Sign> {
         let opaque_liveness_data = OpaqueLivenessData::from(liveness_data);
         let signer = self.validator_signer_factory.new_signer(validator_key);
 
         let signature = signer.sign(&opaque_liveness_data).await.map_err(|error| {
             tracing::error!(message = "Signing failed", ?error);
-            SignError::SigningFailed
+            error::Sign::SigningFailed
         })?;
 
         Ok((opaque_liveness_data, signature))
@@ -257,18 +172,18 @@ where
     /// Do enroll with provided liveness data.
     async fn do_enroll(&self, liveness_data: LivenessData) -> Result<
         EnrollResponse,
-        FlowBaseError<robonode_client::EnrollError>
+        error::shared::FlowBaseError<robonode_client::EnrollError>
     > {
         info!("Bioauth flow - enrolling in progress");
 
         let public_key =
             rpc_validator_key_logic::validator_public_key(&self.validator_key_extractor)
-            .map_err(FlowBaseError::KeyExtraction)?;
+            .map_err(error::shared::FlowBaseError::KeyExtraction)?;
 
         let (opaque_liveness_data, signature) = self
             .sign(public_key.clone(), &liveness_data)
             .await
-            .map_err(FlowBaseError::Sign)?;
+            .map_err(error::shared::FlowBaseError::Sign)?;
 
         let response = self
             .robonode_client
@@ -279,7 +194,7 @@ where
                 public_key: public_key.as_ref(),
             })
             .await
-            .map_err(FlowBaseError::RobonodeClient)?;
+            .map_err(error::shared::FlowBaseError::RobonodeClient)?;
 
         info!("Bioauth flow - enrolling complete");
 
@@ -289,18 +204,18 @@ where
     /// Do authenticate with provided liveness data.
     async fn do_authenticate(&self, liveness_data: LivenessData) -> Result<
         AuthenticateResponse,
-        FlowBaseError<robonode_client::AuthenticateError>
+        error::shared::FlowBaseError<robonode_client::AuthenticateError>
     > {
         info!("Bioauth flow - authentication in progress");
 
         let public_key =
             rpc_validator_key_logic::validator_public_key(&self.validator_key_extractor)
-            .map_err(FlowBaseError::KeyExtraction)?;
+            .map_err(error::shared::FlowBaseError::KeyExtraction)?;
 
         let (opaque_liveness_data, signature) = self
             .sign(public_key, &liveness_data)
             .await
-            .map_err(FlowBaseError::Sign)?;
+            .map_err(error::shared::FlowBaseError::Sign)?;
 
         let response = self
             .robonode_client
@@ -310,7 +225,7 @@ where
                 liveness_data_signature: signature.as_ref(),
             })
             .await
-            .map_err(FlowBaseError::RobonodeClient)?;
+            .map_err(error::shared::FlowBaseError::RobonodeClient)?;
 
         info!("Bioauth flow - authentication complete");
 
@@ -352,8 +267,8 @@ where
     ValidatorKeyExtractor: KeyExtractorT,
     ValidatorKeyExtractor::PublicKeyType: Encode + AsRef<[u8]> + Clone,
     ValidatorKeyExtractor::Error: std::fmt::Debug,
-    ValidatorSignerFactory: SignerFactory<Vec<u8>, ValidatorKeyExtractor::PublicKeyType>,
-    <<ValidatorSignerFactory as SignerFactory<Vec<u8>, ValidatorKeyExtractor::PublicKeyType>>::Signer as Signer<Vec<u8>>>::Error:
+    ValidatorSignerFactory: signer::Factory<Vec<u8>, ValidatorKeyExtractor::PublicKeyType>,
+    <<ValidatorSignerFactory as signer::Factory<Vec<u8>, ValidatorKeyExtractor::PublicKeyType>>::Signer as Signer<Vec<u8>>>::Error:
         std::error::Error + 'static,
     Client: HeaderBackend<Block>,
     Client: ProvideRuntimeApi<Block>,
@@ -364,13 +279,13 @@ where
     Timestamp: Encode + Decode,
     TransactionPool: TransactionPoolT<Block = Block>,
 {
-    async fn get_facetec_device_sdk_params(&self) -> RpcResult<FacetecDeviceSdkParams> {
+    async fn get_facetec_device_sdk_params(&self) -> RpcResult<data::FacetecDeviceSdkParams> {
         let res = self
             .robonode_client
             .as_ref()
             .get_facetec_device_sdk_params()
             .await
-            .map_err(GetFacetecDeviceSdkParamsError::Robonode)?;
+            .map_err(method::get_facetec_device_sdk_params::Error::Robonode)?;
         Ok(res)
     }
 
@@ -380,15 +295,15 @@ where
             .as_ref()
             .get_facetec_session_token()
             .await
-            .map_err(GetFacetecSessionToken::Robonode)?;
+            .map_err(method::get_facetec_session_token::Error::Robonode)?;
         Ok(res.session_token)
     }
 
-    async fn status(&self) -> RpcResult<BioauthStatus<Timestamp>> {
+    async fn status(&self) -> RpcResult<data::BioauthStatus<Timestamp>> {
         let own_key = match rpc_validator_key_logic::validator_public_key(&self.validator_key_extractor) {
             Ok(v) => v,
-            Err(rpc_validator_key_logic::Error::MissingValidatorKey) => return Ok(BioauthStatus::Unknown),
-            Err(rpc_validator_key_logic::Error::ValidatorKeyExtraction) => return Err(StatusError::ValidatorKeyExtraction.into()),
+            Err(rpc_validator_key_logic::Error::MissingValidatorKey) => return Ok(data::BioauthStatus::Unknown),
+            Err(rpc_validator_key_logic::Error::ValidatorKeyExtraction) => return Err(method::status::Error::ValidatorKeyExtraction.into()),
         };
 
         // Extract an id of the last imported block.
@@ -398,7 +313,7 @@ where
             .client
             .runtime_api()
             .bioauth_status(at, &own_key)
-            .map_err(StatusError::RuntimeApi)?;
+            .map_err(method::status::Error::RuntimeApi)?;
 
         Ok(status.into())
     }
@@ -406,31 +321,31 @@ where
     async fn enroll(&self, liveness_data: LivenessData) -> RpcResult<()> {
         self.deny_unsafe.check_if_safe()?;
 
-        self.do_enroll(liveness_data).await.map_err(EnrollError)?;
+        self.do_enroll(liveness_data).await.map_err(method::enroll::Error)?;
 
         Ok(())
     }
 
-    async fn enroll_v2(&self, liveness_data: LivenessData) -> RpcResult<EnrollV2Result> {
+    async fn enroll_v2(&self, liveness_data: LivenessData) -> RpcResult<data::EnrollV2Result> {
         self.deny_unsafe.check_if_safe()?;
 
         let EnrollResponse { scan_result_blob } = self
             .do_enroll(liveness_data)
             .await
-            .map_err(EnrollV2Error)?;
+            .map_err(method::enroll_v2::Error)?;
 
-        Ok(EnrollV2Result { scan_result_blob })
+        Ok(data::EnrollV2Result { scan_result_blob })
     }
 
     async fn authenticate(&self, liveness_data: LivenessData) -> RpcResult<TxHash<TransactionPool>> {
         self.deny_unsafe.check_if_safe()?;
 
-        let errtype = |val: errors::authenticate::Error<TransactionPool::Error>| {  val };
+        let errtype = |val: method::authenticate::Error<TransactionPool::Error>| {  val };
 
         let response = self
             .do_authenticate(liveness_data)
             .await
-            .map_err(AuthenticateError::RobonodeRequest)
+            .map_err(method::authenticate::Error::RobonodeRequest)
             .map_err(errtype)?;
 
         info!(message = "We've obtained an auth ticket", auth_ticket = ?response.auth_ticket);
@@ -445,7 +360,7 @@ where
                 response.auth_ticket.into(),
                 response.auth_ticket_signature.into(),
             )
-            .map_err(AuthenticateError::RuntimeApi).map_err(errtype)?;
+            .map_err(method::authenticate::Error::RuntimeApi).map_err(errtype)?;
 
         info!("Bioauth flow - submitting authenticate transaction");
 
@@ -458,7 +373,7 @@ where
                 ext,
             )
             .await
-            .map_err(AuthenticateError::BioauthTx).map_err(errtype)?.fuse();
+            .map_err(method::authenticate::Error::BioauthTx).map_err(errtype)?.fuse();
 
         tokio::spawn(async move {
             loop {
@@ -532,17 +447,17 @@ where
     async fn authenticate_v2(
         &self,
         liveness_data: LivenessData,
-    ) -> RpcResult<AuthenticateV2Result> {
+    ) -> RpcResult<data::AuthenticateV2Result> {
         self.deny_unsafe.check_if_safe()?;
 
         let AuthenticateResponse {
             auth_ticket,
             auth_ticket_signature,
             scan_result_blob,
-        } = self.do_authenticate(liveness_data).await.map_err(AuthenticateV2Error)?;
+        } = self.do_authenticate(liveness_data).await.map_err(method::authenticate_v2::Error)?;
 
         info!(message = "We've obtained an auth ticket", auth_ticket = ?auth_ticket);
 
-        Ok(AuthenticateV2Result { auth_ticket, auth_ticket_signature, scan_result_blob })
+        Ok(data::AuthenticateV2Result { auth_ticket, auth_ticket_signature, scan_result_blob })
     }
 }
diff --git a/crates/bioauth-flow-rpc/src/errors/authenticate.rs b/crates/bioauth-flow-rpc/src/method/authenticate.rs
similarity index 88%
rename from crates/bioauth-flow-rpc/src/errors/authenticate.rs
rename to crates/bioauth-flow-rpc/src/method/authenticate.rs
index 4258ff4d4..30d39c5ea 100644
--- a/crates/bioauth-flow-rpc/src/errors/authenticate.rs
+++ b/crates/bioauth-flow-rpc/src/method/authenticate.rs
@@ -3,14 +3,13 @@
 use sp_api::ApiError;
 use sp_runtime::transaction_validity::InvalidTransaction;
 
-use super::{api_error_code, shared};
-use crate::error_data::{self, BioauthTxErrorDetails};
+use crate::error;
 
 /// The `authenticate` method error kinds.
 #[derive(Debug)]
 pub enum Error<TxPoolError> {
     /// An error that can occur during doing a request to robonode.
-    RobonodeRequest(shared::FlowBaseError<robonode_client::AuthenticateError>),
+    RobonodeRequest(error::shared::FlowBaseError<robonode_client::AuthenticateError>),
     /// An error that can occur during doing a call into runtime api.
     RuntimeApi(ApiError),
     /// An error that can occur with transaction pool logic.
@@ -23,11 +22,12 @@ where
 {
     fn from(err: Error<TxPoolError>) -> Self {
         match err {
-            Error::RobonodeRequest(err) => err.to_jsonrpsee_error::<_, error_data::ShouldRetry>(
-                |call_error| match call_error {
+            Error::RobonodeRequest(err) => {
+                err.to_jsonrpsee_error::<_, error::data::ShouldRetry>(|call_error| match call_error
+                {
                     robonode_client::AuthenticateError::FaceScanRejectedNoBlob
                     | robonode_client::AuthenticateError::FaceScanRejected(_) => {
-                        Some(error_data::ShouldRetry)
+                        Some(error::data::ShouldRetry)
                     }
 
                     robonode_client::AuthenticateError::InvalidLivenessData
@@ -39,21 +39,21 @@ where
                     | robonode_client::AuthenticateError::LogicInternal(_)
                     | robonode_client::AuthenticateError::UnknownCode(_)
                     | robonode_client::AuthenticateError::Unknown(_) => None,
-                },
-            ),
+                })
+            }
             Error::RuntimeApi(err) => {
-                rpc_error_response::simple(api_error_code::RUNTIME_API, err.to_string())
+                rpc_error_response::simple(error::code::RUNTIME_API, err.to_string())
             }
             Error::BioauthTx(err) => {
                 let (message, data) = map_txpool_error(err);
-                rpc_error_response::raw(api_error_code::TRANSACTION, message, data)
+                rpc_error_response::raw(error::code::TRANSACTION, message, data)
             }
         }
     }
 }
 
 /// Convert a transaction pool error into a human-readable.
-fn map_txpool_error<T>(err: T) -> (String, Option<error_data::BioauthTxErrorDetails>)
+fn map_txpool_error<T>(err: T) -> (String, Option<error::data::BioauthTxErrorDetails>)
 where
     T: sc_transaction_pool_api::error::IntoPoolError,
 {
@@ -70,7 +70,7 @@ where
     let (kind, message) = match err {
         // Provide some custom-tweaked error messages for a few select cases:
         Error::InvalidTransaction(InvalidTransaction::BadProof) => (
-            error_data::BioauthTxErrorKind::AuthTicketSignatureInvalid,
+            error::data::BioauthTxErrorKind::AuthTicketSignatureInvalid,
             "Invalid auth ticket signature",
         ),
         Error::InvalidTransaction(InvalidTransaction::Custom(custom_code))
@@ -79,16 +79,16 @@ where
                     as u8) =>
         {
             (
-                error_data::BioauthTxErrorKind::UnableToParseAuthTicket,
+                error::data::BioauthTxErrorKind::UnableToParseAuthTicket,
                 "Unable to parse a validly signed auth ticket",
             )
         }
         Error::InvalidTransaction(InvalidTransaction::Stale) => (
-            error_data::BioauthTxErrorKind::NonceAlreadyUsed,
+            error::data::BioauthTxErrorKind::NonceAlreadyUsed,
             "The auth ticket you provided has already been used",
         ),
         Error::InvalidTransaction(InvalidTransaction::Future) => (
-            error_data::BioauthTxErrorKind::AlreadyAuthenticated,
+            error::data::BioauthTxErrorKind::AlreadyAuthenticated,
             "Active authentication exists currently, and you can't authenticate again yet",
         ),
         // For the rest cases, fallback to simple error rendering.
@@ -97,7 +97,7 @@ where
         }
     };
 
-    let data = BioauthTxErrorDetails {
+    let data = error::data::BioauthTxErrorDetails {
         inner_error: err.to_string(),
         kind,
         message,
@@ -115,13 +115,14 @@ mod tests {
     use rpc_validator_key_logic::Error as ValidatorKeyError;
 
     use super::*;
-    use crate::errors::sign::Error as SignError;
 
     #[test]
     fn error_key_extraction_validator_key_extraction() {
         let error: jsonrpsee::core::Error =
             Error::<sc_transaction_pool_api::error::Error>::RobonodeRequest(
-                shared::FlowBaseError::KeyExtraction(ValidatorKeyError::ValidatorKeyExtraction),
+                error::shared::FlowBaseError::KeyExtraction(
+                    ValidatorKeyError::ValidatorKeyExtraction,
+                ),
             )
             .into();
         let error: ErrorObject = error.into();
@@ -137,7 +138,7 @@ mod tests {
     fn error_key_extraction_missing_validator_key() {
         let error: jsonrpsee::core::Error =
             Error::<sc_transaction_pool_api::error::Error>::RobonodeRequest(
-                shared::FlowBaseError::KeyExtraction(ValidatorKeyError::MissingValidatorKey),
+                error::shared::FlowBaseError::KeyExtraction(ValidatorKeyError::MissingValidatorKey),
             )
             .into();
         let error: ErrorObject = error.into();
@@ -153,7 +154,7 @@ mod tests {
     fn error_sign() {
         let error: jsonrpsee::core::Error =
             Error::<sc_transaction_pool_api::error::Error>::RobonodeRequest(
-                shared::FlowBaseError::Sign(SignError::SigningFailed),
+                error::shared::FlowBaseError::Sign(error::Sign::SigningFailed),
             )
             .into();
         let error: ErrorObject = error.into();
@@ -169,7 +170,7 @@ mod tests {
     fn error_robonode_face_scan_rejected() {
         let error: jsonrpsee::core::Error =
             Error::<sc_transaction_pool_api::error::Error>::RobonodeRequest(
-                shared::FlowBaseError::RobonodeClient(robonode_client::Error::Call(
+                error::shared::FlowBaseError::RobonodeClient(robonode_client::Error::Call(
                     robonode_client::AuthenticateError::FaceScanRejectedNoBlob,
                 )),
             )
@@ -188,7 +189,7 @@ mod tests {
     fn error_robonode_logic_internal() {
         let error: jsonrpsee::core::Error =
             Error::<sc_transaction_pool_api::error::Error>::RobonodeRequest(
-                shared::FlowBaseError::RobonodeClient(robonode_client::Error::Call(
+                error::shared::FlowBaseError::RobonodeClient(robonode_client::Error::Call(
                     robonode_client::AuthenticateError::LogicInternalNoBlob,
                 )),
             )
@@ -207,7 +208,7 @@ mod tests {
     fn error_robonode_other() {
         let error: jsonrpsee::core::Error =
             Error::<sc_transaction_pool_api::error::Error>::RobonodeRequest(
-                shared::FlowBaseError::RobonodeClient(robonode_client::Error::Call(
+                error::shared::FlowBaseError::RobonodeClient(robonode_client::Error::Call(
                     robonode_client::AuthenticateError::Unknown("test".to_owned()),
                 )),
             )
diff --git a/crates/bioauth-flow-rpc/src/errors/authenticate_v2.rs b/crates/bioauth-flow-rpc/src/method/authenticate_v2.rs
similarity index 80%
rename from crates/bioauth-flow-rpc/src/errors/authenticate_v2.rs
rename to crates/bioauth-flow-rpc/src/method/authenticate_v2.rs
index 244cc75f3..c8ad9ee33 100644
--- a/crates/bioauth-flow-rpc/src/errors/authenticate_v2.rs
+++ b/crates/bioauth-flow-rpc/src/method/authenticate_v2.rs
@@ -1,25 +1,24 @@
 //! The `authenticate_v2` method error.
 
-use super::shared;
-use crate::error_data;
+use crate::error;
 
 /// The `authenticate_v2` method error kinds.
 #[derive(Debug)]
-pub struct Error(pub shared::FlowBaseError<robonode_client::AuthenticateError>);
+pub struct Error(pub error::shared::FlowBaseError<robonode_client::AuthenticateError>);
 
 impl From<Error> for jsonrpsee::core::Error {
     fn from(err: Error) -> Self {
         err.0
-            .to_jsonrpsee_error::<_, error_data::BlobOrRetry>(|call_error| match call_error {
+            .to_jsonrpsee_error::<_, error::data::BlobOrRetry>(|call_error| match call_error {
                 robonode_client::AuthenticateError::PersonNotFound(ref scan_result_blob)
                 | robonode_client::AuthenticateError::FaceScanRejected(ref scan_result_blob)
                 | robonode_client::AuthenticateError::SignatureInvalid(ref scan_result_blob)
                 | robonode_client::AuthenticateError::LogicInternal(ref scan_result_blob) => {
-                    Some(error_data::ScanResultBlob(scan_result_blob.clone()).into())
+                    Some(error::data::ScanResultBlob(scan_result_blob.clone()).into())
                 }
 
                 robonode_client::AuthenticateError::FaceScanRejectedNoBlob => {
-                    Some(error_data::ShouldRetry.into())
+                    Some(error::data::ShouldRetry.into())
                 }
 
                 robonode_client::AuthenticateError::InvalidLivenessData
@@ -39,11 +38,10 @@ mod tests {
     use rpc_validator_key_logic::Error as ValidatorKeyError;
 
     use super::*;
-    use crate::errors::sign::Error as SignError;
 
     #[test]
     fn error_key_extraction_validator_key_extraction() {
-        let error: jsonrpsee::core::Error = Error(shared::FlowBaseError::KeyExtraction(
+        let error: jsonrpsee::core::Error = Error(error::shared::FlowBaseError::KeyExtraction(
             ValidatorKeyError::ValidatorKeyExtraction,
         ))
         .into();
@@ -58,7 +56,7 @@ mod tests {
 
     #[test]
     fn error_key_extraction_missing_validator_key() {
-        let error: jsonrpsee::core::Error = Error(shared::FlowBaseError::KeyExtraction(
+        let error: jsonrpsee::core::Error = Error(error::shared::FlowBaseError::KeyExtraction(
             ValidatorKeyError::MissingValidatorKey,
         ))
         .into();
@@ -73,8 +71,10 @@ mod tests {
 
     #[test]
     fn error_sign() {
-        let error: jsonrpsee::core::Error =
-            Error(shared::FlowBaseError::Sign(SignError::SigningFailed)).into();
+        let error: jsonrpsee::core::Error = Error(error::shared::FlowBaseError::Sign(
+            error::Sign::SigningFailed,
+        ))
+        .into();
         let error: ErrorObject = error.into();
 
         let expected_error_message = "{\"code\":100,\"message\":\"signing failed\"}";
@@ -86,7 +86,7 @@ mod tests {
 
     #[test]
     fn error_robonode_face_scan_rejected() {
-        let error: jsonrpsee::core::Error = Error(shared::FlowBaseError::RobonodeClient(
+        let error: jsonrpsee::core::Error = Error(error::shared::FlowBaseError::RobonodeClient(
             robonode_client::Error::Call(robonode_client::AuthenticateError::FaceScanRejected(
                 "scan result blob".to_owned(),
             )),
@@ -104,7 +104,7 @@ mod tests {
 
     #[test]
     fn error_robonode_logic_internal() {
-        let error: jsonrpsee::core::Error = Error(shared::FlowBaseError::RobonodeClient(
+        let error: jsonrpsee::core::Error = Error(error::shared::FlowBaseError::RobonodeClient(
             robonode_client::Error::Call(robonode_client::AuthenticateError::LogicInternal(
                 "scan result blob".to_owned(),
             )),
@@ -122,7 +122,7 @@ mod tests {
 
     #[test]
     fn error_robonode_other() {
-        let error: jsonrpsee::core::Error = Error(shared::FlowBaseError::RobonodeClient(
+        let error: jsonrpsee::core::Error = Error(error::shared::FlowBaseError::RobonodeClient(
             robonode_client::Error::Call(robonode_client::AuthenticateError::Unknown(
                 "test".to_owned(),
             )),
diff --git a/crates/bioauth-flow-rpc/src/errors/enroll.rs b/crates/bioauth-flow-rpc/src/method/enroll.rs
similarity index 80%
rename from crates/bioauth-flow-rpc/src/errors/enroll.rs
rename to crates/bioauth-flow-rpc/src/method/enroll.rs
index 857a92dd7..613e667ef 100644
--- a/crates/bioauth-flow-rpc/src/errors/enroll.rs
+++ b/crates/bioauth-flow-rpc/src/method/enroll.rs
@@ -1,19 +1,18 @@
 //! The `enroll` method error.
 
-use super::shared;
-use crate::error_data;
+use crate::error;
 
 /// The `enroll` method error kinds.
 #[derive(Debug)]
-pub struct Error(pub shared::FlowBaseError<robonode_client::EnrollError>);
+pub struct Error(pub error::shared::FlowBaseError<robonode_client::EnrollError>);
 
 impl From<Error> for jsonrpsee::core::Error {
     fn from(err: Error) -> Self {
         err.0
-            .to_jsonrpsee_error::<_, error_data::ShouldRetry>(|call_error| match call_error {
+            .to_jsonrpsee_error::<_, error::data::ShouldRetry>(|call_error| match call_error {
                 robonode_client::EnrollError::FaceScanRejectedNoBlob
                 | robonode_client::EnrollError::FaceScanRejected(_) => {
-                    Some(error_data::ShouldRetry)
+                    Some(error::data::ShouldRetry)
                 }
 
                 robonode_client::EnrollError::InvalidPublicKey
@@ -36,11 +35,10 @@ mod tests {
     use rpc_validator_key_logic::Error as ValidatorKeyError;
 
     use super::*;
-    use crate::errors::sign::Error as SignError;
 
     #[test]
     fn error_key_extraction_validator_key_extraction() {
-        let error: jsonrpsee::core::Error = Error(shared::FlowBaseError::KeyExtraction(
+        let error: jsonrpsee::core::Error = Error(error::shared::FlowBaseError::KeyExtraction(
             ValidatorKeyError::ValidatorKeyExtraction,
         ))
         .into();
@@ -55,7 +53,7 @@ mod tests {
 
     #[test]
     fn error_key_extraction_missing_validator_key() {
-        let error: jsonrpsee::core::Error = Error(shared::FlowBaseError::KeyExtraction(
+        let error: jsonrpsee::core::Error = Error(error::shared::FlowBaseError::KeyExtraction(
             ValidatorKeyError::MissingValidatorKey,
         ))
         .into();
@@ -70,7 +68,7 @@ mod tests {
 
     #[test]
     fn error_robonode_face_scan_rejected() {
-        let error: jsonrpsee::core::Error = Error(shared::FlowBaseError::RobonodeClient(
+        let error: jsonrpsee::core::Error = Error(error::shared::FlowBaseError::RobonodeClient(
             robonode_client::Error::Call(robonode_client::EnrollError::FaceScanRejectedNoBlob),
         ))
         .into();
@@ -86,7 +84,7 @@ mod tests {
 
     #[test]
     fn error_robonode_logic_internal() {
-        let error: jsonrpsee::core::Error = Error(shared::FlowBaseError::RobonodeClient(
+        let error: jsonrpsee::core::Error = Error(error::shared::FlowBaseError::RobonodeClient(
             robonode_client::Error::Call(robonode_client::EnrollError::LogicInternalNoBlob),
         ))
         .into();
@@ -102,7 +100,7 @@ mod tests {
 
     #[test]
     fn error_robonode_other() {
-        let error: jsonrpsee::core::Error = Error(shared::FlowBaseError::RobonodeClient(
+        let error: jsonrpsee::core::Error = Error(error::shared::FlowBaseError::RobonodeClient(
             robonode_client::Error::Call(robonode_client::EnrollError::Unknown("test".to_owned())),
         ))
         .into();
@@ -118,8 +116,10 @@ mod tests {
 
     #[test]
     fn error_sign() {
-        let error: jsonrpsee::core::Error =
-            Error(shared::FlowBaseError::Sign(SignError::SigningFailed)).into();
+        let error: jsonrpsee::core::Error = Error(error::shared::FlowBaseError::Sign(
+            error::Sign::SigningFailed,
+        ))
+        .into();
         let error: ErrorObject = error.into();
 
         let expected_error_message = "{\"code\":100,\"message\":\"signing failed\"}";
diff --git a/crates/bioauth-flow-rpc/src/errors/enroll_v2.rs b/crates/bioauth-flow-rpc/src/method/enroll_v2.rs
similarity index 80%
rename from crates/bioauth-flow-rpc/src/errors/enroll_v2.rs
rename to crates/bioauth-flow-rpc/src/method/enroll_v2.rs
index 576571c4b..e59babc2b 100644
--- a/crates/bioauth-flow-rpc/src/errors/enroll_v2.rs
+++ b/crates/bioauth-flow-rpc/src/method/enroll_v2.rs
@@ -1,24 +1,23 @@
 //! The `enroll_v2` method error.
 
-use super::shared;
-use crate::error_data;
+use crate::error;
 
 /// The `enroll_v2` method error kinds.
 #[derive(Debug)]
-pub struct Error(pub shared::FlowBaseError<robonode_client::EnrollError>);
+pub struct Error(pub error::shared::FlowBaseError<robonode_client::EnrollError>);
 
 impl From<Error> for jsonrpsee::core::Error {
     fn from(err: Error) -> Self {
         err.0
-            .to_jsonrpsee_error::<_, error_data::BlobOrRetry>(|call_error| match call_error {
+            .to_jsonrpsee_error::<_, error::data::BlobOrRetry>(|call_error| match call_error {
                 robonode_client::EnrollError::FaceScanRejected(ref scan_result_blob)
                 | robonode_client::EnrollError::PersonAlreadyEnrolled(ref scan_result_blob)
                 | robonode_client::EnrollError::LogicInternal(ref scan_result_blob) => {
-                    Some(error_data::ScanResultBlob(scan_result_blob.clone()).into())
+                    Some(error::data::ScanResultBlob(scan_result_blob.clone()).into())
                 }
 
                 robonode_client::EnrollError::FaceScanRejectedNoBlob => {
-                    Some(error_data::ShouldRetry.into())
+                    Some(error::data::ShouldRetry.into())
                 }
 
                 robonode_client::EnrollError::InvalidPublicKey
@@ -39,11 +38,10 @@ mod tests {
     use rpc_validator_key_logic::Error as ValidatorKeyError;
 
     use super::*;
-    use crate::errors::sign::Error as SignError;
 
     #[test]
     fn error_key_extraction_validator_key_extraction() {
-        let error: jsonrpsee::core::Error = Error(shared::FlowBaseError::KeyExtraction(
+        let error: jsonrpsee::core::Error = Error(error::shared::FlowBaseError::KeyExtraction(
             ValidatorKeyError::ValidatorKeyExtraction,
         ))
         .into();
@@ -58,7 +56,7 @@ mod tests {
 
     #[test]
     fn error_key_extraction_missing_validator_key() {
-        let error: jsonrpsee::core::Error = Error(shared::FlowBaseError::KeyExtraction(
+        let error: jsonrpsee::core::Error = Error(error::shared::FlowBaseError::KeyExtraction(
             ValidatorKeyError::MissingValidatorKey,
         ))
         .into();
@@ -73,7 +71,7 @@ mod tests {
 
     #[test]
     fn error_robonode_face_scan_rejected() {
-        let error: jsonrpsee::core::Error = Error(shared::FlowBaseError::RobonodeClient(
+        let error: jsonrpsee::core::Error = Error(error::shared::FlowBaseError::RobonodeClient(
             robonode_client::Error::Call(robonode_client::EnrollError::FaceScanRejected(
                 "scan result blob".to_owned(),
             )),
@@ -91,7 +89,7 @@ mod tests {
 
     #[test]
     fn error_robonode_logic_internal() {
-        let error: jsonrpsee::core::Error = Error(shared::FlowBaseError::RobonodeClient(
+        let error: jsonrpsee::core::Error = Error(error::shared::FlowBaseError::RobonodeClient(
             robonode_client::Error::Call(robonode_client::EnrollError::LogicInternal(
                 "scan result blob".to_owned(),
             )),
@@ -109,7 +107,7 @@ mod tests {
 
     #[test]
     fn error_robonode_other() {
-        let error: jsonrpsee::core::Error = Error(shared::FlowBaseError::RobonodeClient(
+        let error: jsonrpsee::core::Error = Error(error::shared::FlowBaseError::RobonodeClient(
             robonode_client::Error::Call(robonode_client::EnrollError::Unknown("test".to_owned())),
         ))
         .into();
@@ -125,8 +123,10 @@ mod tests {
 
     #[test]
     fn error_sign() {
-        let error: jsonrpsee::core::Error =
-            Error(shared::FlowBaseError::Sign(SignError::SigningFailed)).into();
+        let error: jsonrpsee::core::Error = Error(error::shared::FlowBaseError::Sign(
+            error::Sign::SigningFailed,
+        ))
+        .into();
         let error: ErrorObject = error.into();
 
         let expected_error_message = "{\"code\":100,\"message\":\"signing failed\"}";
diff --git a/crates/bioauth-flow-rpc/src/errors/get_facetec_device_sdk_params.rs b/crates/bioauth-flow-rpc/src/method/get_facetec_device_sdk_params.rs
similarity index 90%
rename from crates/bioauth-flow-rpc/src/errors/get_facetec_device_sdk_params.rs
rename to crates/bioauth-flow-rpc/src/method/get_facetec_device_sdk_params.rs
index a3e43a324..646c2635e 100644
--- a/crates/bioauth-flow-rpc/src/errors/get_facetec_device_sdk_params.rs
+++ b/crates/bioauth-flow-rpc/src/method/get_facetec_device_sdk_params.rs
@@ -1,6 +1,6 @@
 //! The `get_facetec_device_sdk_params` method error.
 
-use super::api_error_code;
+use crate::error;
 
 /// The `get_facetec_device_sdk_params` method error kinds.
 #[derive(Debug)]
@@ -13,7 +13,7 @@ impl From<Error> for jsonrpsee::core::Error {
     fn from(err: Error) -> Self {
         match err {
             Error::Robonode(err) => {
-                rpc_error_response::simple(api_error_code::ROBONODE, err.to_string())
+                rpc_error_response::simple(error::code::ROBONODE, err.to_string())
             }
         }
     }
diff --git a/crates/bioauth-flow-rpc/src/errors/get_facetec_session_token.rs b/crates/bioauth-flow-rpc/src/method/get_facetec_session_token.rs
similarity index 90%
rename from crates/bioauth-flow-rpc/src/errors/get_facetec_session_token.rs
rename to crates/bioauth-flow-rpc/src/method/get_facetec_session_token.rs
index 83cf32c9f..fa320ed9b 100644
--- a/crates/bioauth-flow-rpc/src/errors/get_facetec_session_token.rs
+++ b/crates/bioauth-flow-rpc/src/method/get_facetec_session_token.rs
@@ -1,6 +1,6 @@
 //! The `get_facetec_session_token` method error.
 
-use super::api_error_code;
+use crate::error;
 
 /// The `get_facetec_session_token` method error kinds.
 #[derive(Debug)]
@@ -13,7 +13,7 @@ impl From<Error> for jsonrpsee::core::Error {
     fn from(err: Error) -> Self {
         match err {
             Error::Robonode(err) => {
-                rpc_error_response::simple(api_error_code::ROBONODE, err.to_string())
+                rpc_error_response::simple(error::code::ROBONODE, err.to_string())
             }
         }
     }
diff --git a/crates/bioauth-flow-rpc/src/method/mod.rs b/crates/bioauth-flow-rpc/src/method/mod.rs
new file mode 100644
index 000000000..38324d669
--- /dev/null
+++ b/crates/bioauth-flow-rpc/src/method/mod.rs
@@ -0,0 +1,9 @@
+//! Module implementation details.
+
+pub mod authenticate;
+pub mod authenticate_v2;
+pub mod enroll;
+pub mod enroll_v2;
+pub mod get_facetec_device_sdk_params;
+pub mod get_facetec_session_token;
+pub mod status;
diff --git a/crates/bioauth-flow-rpc/src/errors/status.rs b/crates/bioauth-flow-rpc/src/method/status.rs
similarity index 93%
rename from crates/bioauth-flow-rpc/src/errors/status.rs
rename to crates/bioauth-flow-rpc/src/method/status.rs
index 1e6c46bc4..7a3fa4871 100644
--- a/crates/bioauth-flow-rpc/src/errors/status.rs
+++ b/crates/bioauth-flow-rpc/src/method/status.rs
@@ -3,7 +3,7 @@
 use rpc_validator_key_logic::Error as ValidatorKeyError;
 use sp_api::ApiError;
 
-use super::api_error_code;
+use crate::error;
 
 /// The `status` method error kinds.
 #[derive(Debug)]
@@ -19,11 +19,11 @@ impl From<Error> for jsonrpsee::core::Error {
     fn from(err: Error) -> Self {
         match err {
             Error::ValidatorKeyExtraction => rpc_error_response::simple(
-                api_error_code::VALIDATOR_KEY_EXTRACTION,
+                error::code::VALIDATOR_KEY_EXTRACTION,
                 ValidatorKeyError::ValidatorKeyExtraction.to_string(),
             ),
             Error::RuntimeApi(err) => rpc_error_response::simple(
-                api_error_code::RUNTIME_API,
+                error::code::RUNTIME_API,
                 format!("unable to get status from the runtime: {err}"),
             ),
         }
diff --git a/crates/bioauth-flow-rpc/src/signer.rs b/crates/bioauth-flow-rpc/src/signer.rs
new file mode 100644
index 000000000..073fd5029
--- /dev/null
+++ b/crates/bioauth-flow-rpc/src/signer.rs
@@ -0,0 +1,36 @@
+//! Signer.
+
+/// Signer provides signatures for the data.
+#[async_trait::async_trait]
+pub trait Signer<S> {
+    /// Signature error.
+    /// Error may originate from communicating with HSM, or from a thread pool failure, etc.
+    type Error;
+
+    /// Sign the provided data and return the signature, or an error if the signing fails.
+    async fn sign<'a, D>(&self, data: D) -> std::result::Result<S, Self::Error>
+    where
+        D: AsRef<[u8]> + Send + 'a;
+}
+
+/// A factory that spits out [`Signer`]s.
+pub trait Factory<S, K> {
+    /// The type of [`Signer`] this factory will create.
+    type Signer: Signer<S>;
+
+    /// Create a [`Signer`] using the provided public key.
+    fn new_signer(&self, key: K) -> Self::Signer;
+}
+
+impl<S, T, F, K, P> Factory<T, K> for P
+where
+    P: std::ops::Deref<Target = F>,
+    F: Fn(K) -> S,
+    S: Signer<T>,
+{
+    type Signer = S;
+
+    fn new_signer(&self, key: K) -> Self::Signer {
+        self(key)
+    }
+}
diff --git a/crates/humanode-rpc/src/lib.rs b/crates/humanode-rpc/src/lib.rs
index 881e8653c..512f1e2e4 100644
--- a/crates/humanode-rpc/src/lib.rs
+++ b/crates/humanode-rpc/src/lib.rs
@@ -4,7 +4,7 @@ use std::{collections::BTreeMap, sync::Arc};
 
 use author_ext_api::AuthorExtApi;
 use author_ext_rpc::{AuthorExt, AuthorExtServer};
-use bioauth_flow_rpc::{Bioauth, BioauthServer, Signer, SignerFactory};
+use bioauth_flow_rpc::{signer, Bioauth, BioauthServer, Signer};
 use bioauth_keys::traits::KeyExtractor as KeyExtractorT;
 use fc_rpc::{
     Eth, EthApiServer, EthBlockDataCacheTask, EthConfig, EthFilter, EthFilterApiServer, EthPubSub,
@@ -175,9 +175,9 @@ where
     VKE: KeyExtractorT + Send + Sync + 'static,
     VKE::PublicKeyType: Encode + AsRef<[u8]> + Clone + Send + Sync + sp_runtime::Serialize,
     VKE::Error: std::fmt::Debug,
-    VSF: SignerFactory<Vec<u8>, VKE::PublicKeyType> + Send + Sync + 'static,
+    VSF: signer::Factory<Vec<u8>, VKE::PublicKeyType> + Send + Sync + 'static,
     VSF::Signer: Send + Sync + 'static,
-    <<VSF as SignerFactory<Vec<u8>, VKE::PublicKeyType>>::Signer as Signer<Vec<u8>>>::Error:
+    <<VSF as signer::Factory<Vec<u8>, VKE::PublicKeyType>>::Signer as Signer<Vec<u8>>>::Error:
         std::error::Error + 'static,
     A: ChainApi<Block = Block> + 'static,
     SC: SelectChain<Block> + 'static,