diff --git a/src/certificate.rs b/src/certificate.rs
index f8c84ac..f5d6537 100644
--- a/src/certificate.rs
+++ b/src/certificate.rs
@@ -15,10 +15,11 @@
  */
 
 use crate::certificate::CertificateError::{
-    CertificateLengthError, DecodeError, ExpirationError, KeyInCertificateError, MalformedRoot,
-    NoTrustedRoot, VerificationError,
+    CertificateLengthError, DecodeError, DecodeTrustError, ExpirationError, IncorrectByteLength,
+    IncorrectCertificateFormat, KeyInCertificateError, MalformedRoot, NoTrustedRoot,
+    VerificationError,
 };
-use crate::trust::{Trust, TRUST_LEN};
+use crate::trust::{Trust, TrustError, TRUST_LEN};
 use fluence_identity::key_pair::KeyPair;
 use fluence_identity::public_key::PublicKey;
 use std::str::FromStr;
@@ -40,8 +41,12 @@ pub struct Certificate {
 
 #[derive(ThisError, Debug)]
 pub enum CertificateError {
-    #[error("Error while decoding a certificate: {0}")]
-    DecodeError(String),
+    #[error("Incorrect format of the certificate: {0}")]
+    IncorrectCertificateFormat(String),
+    #[error("Incorrect length of an array. Should be 2 bytes of a format, 4 bytes of a version and 104 bytes for each trust")]
+    IncorrectByteLength,
+    #[error("Error while decoding a trust in a certificate: {0}")]
+    DecodeError(TrustError),
     #[error("Certificate is expired. Issued at {issued_at} and expired at {expires_at}")]
     ExpirationError {
         expires_at: String,
@@ -50,21 +55,17 @@ pub enum CertificateError {
     #[error("Certificate does not contain a trusted root.")]
     NoTrustedRoot,
     #[error("Root trust did not pass verification: {0}")]
-    MalformedRoot(String),
+    MalformedRoot(TrustError),
     #[error("There is no `issued_by` public key in a certificate")]
     KeyInCertificateError,
     #[error("The certificate must have at least 1 trust")]
     CertificateLengthError,
+    #[error("Cannot convert trust number {0} from string: {1}")]
+    DecodeTrustError(usize, TrustError),
     #[error("Trust {0} in chain did not pass verification: {1}")]
-    VerificationError(usize, String),
-    #[error("Unexpected error: {0}")]
-    Unexpected(String),
-}
-
-impl From<CertificateError> for String {
-    fn from(err: CertificateError) -> Self {
-        format!("{}", err)
-    }
+    VerificationError(usize, TrustError),
+    #[error("there cannot be paths without any nodes after adding verified certificates")]
+    Unexpected,
 }
 
 impl Certificate {
@@ -156,8 +157,7 @@ impl Certificate {
 
         // check root trust and its existence in trusted roots list
         let root = &chain[0];
-        Trust::verify(root, &root.issued_for, cur_time)
-            .map_err(|e| MalformedRoot(format!("{}", e)))?;
+        Trust::verify(root, &root.issued_for, cur_time).map_err(|e| MalformedRoot(e))?;
         if !trusted_roots.contains(&root.issued_for) {
             return Err(NoTrustedRoot);
         }
@@ -169,7 +169,7 @@ impl Certificate {
             let trust_giver = &chain[trust_id - 1];
 
             Trust::verify(trust, &trust_giver.issued_for, cur_time)
-                .map_err(|e| VerificationError(trust_id, format!("{}", e)))?;
+                .map_err(|e| VerificationError(trust_id, e))?;
         }
 
         Ok(())
@@ -195,7 +195,7 @@ impl Certificate {
     pub fn decode(arr: &[u8]) -> Result<Self, CertificateError> {
         let trusts_offset = arr.len() - 2 - 4;
         if trusts_offset % TRUST_LEN != 0 {
-            return Err(DecodeError("Incorrect length of an array. Should be 2 bytes of a format, 4 bytes of a version and 104 bytes for each trust. ".to_string()));
+            return Err(IncorrectByteLength);
         }
 
         let number_of_trusts = trusts_offset / TRUST_LEN;
@@ -214,7 +214,7 @@ impl Certificate {
             let from = i * TRUST_LEN + 6;
             let to = (i + 1) * TRUST_LEN + 6;
             let slice = &arr[from..to];
-            let t = Trust::decode(slice).map_err(|e| DecodeError(format!("{}", e)))?;
+            let t = Trust::decode(slice).map_err(|e| DecodeError(e))?;
             chain.push(t);
         }
 
@@ -244,10 +244,7 @@ impl FromStr for Certificate {
         let _version = str_lines[1];
 
         if (str_lines.len() - 2) % 4 != 0 {
-            return Err(DecodeError(format!(
-                "Incorrect format of the certificate: {}",
-                s
-            )));
+            return Err(IncorrectCertificateFormat(s.to_string()));
         }
 
         let num_of_trusts = (str_lines.len() - 2) / 4;
@@ -260,12 +257,7 @@ impl FromStr for Certificate {
                 str_lines[i + 2],
                 str_lines[i + 3],
             )
-            .map_err(|e| {
-                DecodeError(format!(
-                    "Cannot convert trust number {} from string: {}",
-                    i, e
-                ))
-            })?;
+            .map_err(|e| DecodeTrustError(i, e))?;
 
             trusts.push(trust);
         }
diff --git a/src/public_key_hashable.rs b/src/public_key_hashable.rs
index 1bccaa7..0bc0dea 100644
--- a/src/public_key_hashable.rs
+++ b/src/public_key_hashable.rs
@@ -16,7 +16,9 @@
 
 use fluence_identity::public_key::PublicKey;
 
+use crate::public_key_hashable::PkError::{Base58DecodeError, BytesDecodeError};
 use core::fmt;
+use ed25519_dalek::SignatureError;
 use ref_cast::RefCast;
 use serde::ser::Serializer;
 use std::str::FromStr;
@@ -24,6 +26,7 @@ use std::{
     fmt::{Display, Formatter},
     hash::{Hash, Hasher},
 };
+use thiserror::Error as ThisError;
 
 /// Wrapper to use PublicKey in HashMap
 #[derive(PartialEq, Eq, Debug, Clone, RefCast)]
@@ -81,16 +84,23 @@ impl Display for PublicKeyHashable {
     }
 }
 
+#[derive(ThisError, Debug)]
+pub enum PkError {
+    #[error("Invalid string '{0}': {1}")]
+    Base58DecodeError(String, bs58::decode::Error),
+    #[error("Invalid bytes {0:?}: {1}")]
+    BytesDecodeError(Vec<u8>, SignatureError),
+}
+
 impl FromStr for PublicKeyHashable {
-    type Err = String;
+    type Err = PkError;
 
     fn from_str(s: &str) -> Result<Self, Self::Err> {
         let bytes = bs58::decode(s)
             .into_vec()
-            .map_err(|err| format!("Invalid string '{}': {}", s, err))?;
+            .map_err(|err| Base58DecodeError(s.to_string(), err))?;
 
-        let pk = PublicKey::from_bytes(&bytes)
-            .map_err(|err| format!("Invalid bytes {:?}: {}", bytes, err))?;
+        let pk = PublicKey::from_bytes(&bytes).map_err(|err| BytesDecodeError(bytes, err))?;
         Ok(PublicKeyHashable::from(pk))
     }
 }
diff --git a/src/trust.rs b/src/trust.rs
index 74a5721..8b1a35a 100644
--- a/src/trust.rs
+++ b/src/trust.rs
@@ -64,11 +64,11 @@ pub enum TrustError {
     Expired(Duration, Duration),
 
     /// Errors occured on signature verification
-    #[error("{0:?}")]
+    #[error("{0}")]
     SignatureError(String),
 
     /// Errors occured on trust decoding from differrent formats
-    #[error("{0:?}")]
+    #[error("{0}")]
     DecodeError(String),
 }
 
diff --git a/src/trust_graph.rs b/src/trust_graph.rs
index 7d2f55f..34f9792 100644
--- a/src/trust_graph.rs
+++ b/src/trust_graph.rs
@@ -21,10 +21,11 @@ use crate::revoke::Revoke;
 use crate::revoke::RevokeError;
 use crate::trust::Trust;
 use crate::trust_graph::TrustGraphError::{
-    CertificateCheckError, InternalStorageError, NoRoot, RevokeCheckError,
+    CertificateCheckError, EmptyChain, InternalStorageError, NoRoot, RevokeCheckError,
 };
 use crate::trust_graph_storage::Storage;
 use crate::trust_node::{Auth, TrustNode};
+use crate::StorageError;
 use fluence_identity::public_key::PublicKey;
 use std::borrow::Borrow;
 use std::collections::{HashSet, VecDeque};
@@ -50,15 +51,23 @@ where
 #[derive(ThisError, Debug)]
 pub enum TrustGraphError {
     #[error("Internal storage error: {0}")]
-    InternalStorageError(String),
+    InternalStorageError(Box<dyn StorageError>),
     #[error("There is no root for this certificate.")]
     NoRoot,
+    #[error("Chain is empty")]
+    EmptyChain,
     #[error("Certificate check error: {0}")]
     CertificateCheckError(CertificateError),
     #[error("Error on revoking a trust: {0}")]
     RevokeCheckError(RevokeError),
 }
 
+impl<T: StorageError + 'static> From<T> for TrustGraphError {
+    fn from(err: T) -> Self {
+        InternalStorageError(Box::new(err))
+    }
+}
+
 impl From<CertificateError> for TrustGraphError {
     fn from(err: CertificateError) -> Self {
         CertificateCheckError(err)
@@ -92,16 +101,12 @@ where
         pk: PublicKeyHashable,
         weight: Weight,
     ) -> Result<(), TrustGraphError> {
-        self.storage
-            .add_root_weight(pk, weight)
-            .map_err(|e| InternalStorageError(e.into()))
+        Ok(self.storage.add_root_weight(pk, weight)?)
     }
 
     /// Get trust by public key
     pub fn get(&self, pk: PublicKey) -> Result<Option<TrustNode>, TrustGraphError> {
-        self.storage
-            .get(&pk.into())
-            .map_err(|e| InternalStorageError(e.into()))
+        Ok(self.storage.get(&pk.into())?)
     }
 
     // TODO: remove cur_time from api, leave it for tests only
@@ -112,8 +117,7 @@ where
     {
         let roots: Vec<PublicKey> = self
             .storage
-            .root_keys()
-            .map_err(|e| InternalStorageError(e.into()))?
+            .root_keys()?
             .iter()
             .cloned()
             .map(Into::into)
@@ -122,28 +126,18 @@ where
         Certificate::verify(cert.borrow(), roots.as_slice(), cur_time)?;
 
         let mut chain = cert.borrow().chain.iter();
-        let root_trust = chain
-            .next()
-            .ok_or("empty chain")
-            .map_err(|e| InternalStorageError(e.into()))?;
+        let root_trust = chain.next().ok_or(EmptyChain)?;
         let root_pk: PublicKeyHashable = root_trust.issued_for.clone().into();
 
         // Insert new TrustNode for this root_pk if there wasn't one
-        if self
-            .storage
-            .get(&root_pk)
-            .map_err(|e| InternalStorageError(e.into()))?
-            .is_none()
-        {
+        if self.storage.get(&root_pk)?.is_none() {
             let mut trust_node = TrustNode::new(root_trust.issued_for.clone(), cur_time);
             let root_auth = Auth {
                 trust: root_trust.clone(),
                 issued_by: root_trust.issued_for.clone(),
             };
             trust_node.update_auth(root_auth);
-            self.storage
-                .insert(root_pk, trust_node)
-                .map_err(|e| InternalStorageError(e.into()))?;
+            self.storage.insert(root_pk, trust_node)?;
         }
 
         // Insert remaining trusts to the graph
@@ -157,8 +151,7 @@ where
             };
 
             self.storage
-                .update_auth(&pk, auth, &root_trust.issued_for, cur_time)
-                .map_err(|e| InternalStorageError(e.into()))?;
+                .update_auth(&pk, auth, &root_trust.issued_for, cur_time)?;
 
             previous_trust = trust;
         }
@@ -171,18 +164,13 @@ where
     where
         P: Borrow<PublicKey>,
     {
-        if let Some(weight) = self
-            .storage
-            .get_root_weight(pk.borrow().as_ref())
-            .map_err(|e| InternalStorageError(e.into()))?
-        {
+        if let Some(weight) = self.storage.get_root_weight(pk.borrow().as_ref())? {
             return Ok(Some(weight));
         }
 
         let roots: Vec<PublicKey> = self
             .storage
-            .root_keys()
-            .map_err(|e| InternalStorageError(e.into()))?
+            .root_keys()?
             .iter()
             .map(|pk| pk.clone().into())
             .collect();
@@ -220,9 +208,7 @@ where
 
             let root_weight = self
                 .storage
-                .get_root_weight(first.issued_for.as_ref())
-                // This panic shouldn't happen // TODO: why?
-                .map_err(|e| InternalStorageError(e.into()))?
+                .get_root_weight(first.issued_for.as_ref())?
                 .ok_or(NoRoot)?;
 
             // certificate weight = root weight + 1 * every other element in the chain
@@ -264,12 +250,8 @@ where
 
             let auths: Vec<Auth> = self
                 .storage
-                .get(&last.issued_by.clone().into())
-                .map_err(|e| InternalStorageError(e.into()))?
-                .ok_or(CertificateCheckError(Unexpected(
-                    "there cannot be paths without any nodes after adding verified certificates"
-                        .to_string(),
-                )))?
+                .get(&last.issued_by.clone().into())?
+                .ok_or(CertificateCheckError(Unexpected))?
                 .authorizations()
                 .cloned()
                 .collect();
@@ -314,16 +296,10 @@ where
         P: Borrow<PublicKey>,
     {
         // get all auths (edges) for issued public key
-        let issued_for_node = self
-            .storage
-            .get(issued_for.borrow().as_ref())
-            .map_err(|e| InternalStorageError(e.into()))?;
+        let issued_for_node = self.storage.get(issued_for.borrow().as_ref())?;
 
         let roots = roots.iter().map(|pk| pk.as_ref());
-        let keys = self
-            .storage
-            .root_keys()
-            .map_err(|e| InternalStorageError(e.into()))?;
+        let keys = self.storage.root_keys()?;
         let roots = keys.iter().chain(roots).collect();
 
         match issued_for_node {
@@ -356,9 +332,7 @@ where
 
         let pk: PublicKeyHashable = revoke.pk.clone().into();
 
-        self.storage
-            .revoke(&pk, revoke)
-            .map_err(|e| InternalStorageError(e.into()))
+        Ok(self.storage.revoke(&pk, revoke)?)
     }
 
     /// Check information about new certificates and about revoked certificates.
diff --git a/src/trust_graph_storage.rs b/src/trust_graph_storage.rs
index ffa19c3..3a79302 100644
--- a/src/trust_graph_storage.rs
+++ b/src/trust_graph_storage.rs
@@ -1,29 +1,29 @@
-use crate::public_key_hashable::PublicKeyHashable;
+use crate::public_key_hashable::PublicKeyHashable as PK;
 use crate::revoke::Revoke;
 use crate::trust_graph::Weight;
 use crate::trust_graph_storage::InMemoryStorageError::RevokeError;
 use crate::trust_node::{Auth, TrustNode};
 use fluence_identity::public_key::PublicKey;
 use std::collections::HashMap;
+use std::fmt::Display;
 use std::time::Duration;
 use thiserror::Error as ThisError;
 
-pub trait StorageError: std::error::Error {}
+pub trait StorageError: std::error::Error + Display {}
 
 pub trait Storage {
-    type Error: StorageError + Into<String>;
+    type Error: StorageError + 'static;
 
-    fn get(&self, pk: &PublicKeyHashable) -> Result<Option<TrustNode>, Self::Error>;
-    fn insert(&mut self, pk: PublicKeyHashable, node: TrustNode) -> Result<(), Self::Error>;
+    fn get(&self, pk: &PK) -> Result<Option<TrustNode>, Self::Error>;
+    fn insert(&mut self, pk: PK, node: TrustNode) -> Result<(), Self::Error>;
 
-    fn get_root_weight(&self, pk: &PublicKeyHashable) -> Result<Option<Weight>, Self::Error>;
-    fn add_root_weight(&mut self, pk: PublicKeyHashable, weight: Weight)
-        -> Result<(), Self::Error>;
-    fn root_keys(&self) -> Result<Vec<PublicKeyHashable>, Self::Error>;
-    fn revoke(&mut self, pk: &PublicKeyHashable, revoke: Revoke) -> Result<(), Self::Error>;
+    fn get_root_weight(&self, pk: &PK) -> Result<Option<Weight>, Self::Error>;
+    fn add_root_weight(&mut self, pk: PK, weight: Weight) -> Result<(), Self::Error>;
+    fn root_keys(&self) -> Result<Vec<PK>, Self::Error>;
+    fn revoke(&mut self, pk: &PK, revoke: Revoke) -> Result<(), Self::Error>;
     fn update_auth(
         &mut self,
-        pk: &PublicKeyHashable,
+        pk: &PK,
         auth: Auth,
         issued_for: &PublicKey,
         cur_time: Duration,
@@ -32,8 +32,8 @@ pub trait Storage {
 
 #[derive(Debug, Default)]
 pub struct InMemoryStorage {
-    nodes: HashMap<PublicKeyHashable, TrustNode>,
-    root_weights: HashMap<PublicKeyHashable, Weight>,
+    nodes: HashMap<PK, TrustNode>,
+    root_weights: HashMap<PK, Weight>,
 }
 
 impl InMemoryStorage {
@@ -64,44 +64,34 @@ pub enum InMemoryStorageError {
     RevokeError(String),
 }
 
-impl From<InMemoryStorageError> for String {
-    fn from(err: InMemoryStorageError) -> Self {
-        err.into()
-    }
-}
-
 impl StorageError for InMemoryStorageError {}
 
 impl Storage for InMemoryStorage {
     type Error = InMemoryStorageError;
 
-    fn get(&self, pk: &PublicKeyHashable) -> Result<Option<TrustNode>, Self::Error> {
+    fn get(&self, pk: &PK) -> Result<Option<TrustNode>, Self::Error> {
         Ok(self.nodes.get(pk).cloned())
     }
 
-    fn insert(&mut self, pk: PublicKeyHashable, node: TrustNode) -> Result<(), Self::Error> {
+    fn insert(&mut self, pk: PK, node: TrustNode) -> Result<(), Self::Error> {
         &self.nodes.insert(pk, node);
         Ok(())
     }
 
-    fn get_root_weight(&self, pk: &PublicKeyHashable) -> Result<Option<Weight>, Self::Error> {
+    fn get_root_weight(&self, pk: &PK) -> Result<Option<Weight>, Self::Error> {
         Ok(self.root_weights.get(pk).cloned())
     }
 
-    fn add_root_weight(
-        &mut self,
-        pk: PublicKeyHashable,
-        weight: Weight,
-    ) -> Result<(), Self::Error> {
+    fn add_root_weight(&mut self, pk: PK, weight: Weight) -> Result<(), Self::Error> {
         &self.root_weights.insert(pk, weight);
         Ok({})
     }
 
-    fn root_keys(&self) -> Result<Vec<PublicKeyHashable>, Self::Error> {
+    fn root_keys(&self) -> Result<Vec<PK>, Self::Error> {
         Ok(self.root_weights.keys().cloned().map(Into::into).collect())
     }
 
-    fn revoke(&mut self, pk: &PublicKeyHashable, revoke: Revoke) -> Result<(), Self::Error> {
+    fn revoke(&mut self, pk: &PK, revoke: Revoke) -> Result<(), Self::Error> {
         match self.nodes.get_mut(&pk) {
             Some(trust_node) => {
                 trust_node.update_revoke(revoke);
@@ -115,7 +105,7 @@ impl Storage for InMemoryStorage {
 
     fn update_auth(
         &mut self,
-        pk: &PublicKeyHashable,
+        pk: &PK,
         auth: Auth,
         issued_for: &PublicKey,
         cur_time: Duration,
diff --git a/bin/Cargo.lock b/wasm/Cargo.lock
similarity index 100%
rename from bin/Cargo.lock
rename to wasm/Cargo.lock
diff --git a/bin/Cargo.toml b/wasm/Cargo.toml
similarity index 100%
rename from bin/Cargo.toml
rename to wasm/Cargo.toml
diff --git a/bin/Config.toml b/wasm/Config.toml
similarity index 100%
rename from bin/Config.toml
rename to wasm/Config.toml
diff --git a/bin/run-repl.sh b/wasm/run-repl.sh
similarity index 100%
rename from bin/run-repl.sh
rename to wasm/run-repl.sh
diff --git a/bin/src/proxy_structs.rs b/wasm/src/dto.rs
similarity index 76%
rename from bin/src/proxy_structs.rs
rename to wasm/src/dto.rs
index 9178854..60302a3 100644
--- a/bin/src/proxy_structs.rs
+++ b/wasm/src/dto.rs
@@ -1,14 +1,13 @@
 use fluence::fce;
-use trust_graph::{Certificate as TGCertificate, Trust as TGTrust};
 
 #[fce]
 pub struct Certificate {
     pub chain: Vec<Trust>,
 }
 
-impl From<TGCertificate> for Certificate {
-    fn from(t: TGCertificate) -> Self {
-        let chain: Vec<Trust> = t.chain.into_iter().map(|t| t.into()).collect();
+impl From<trust_graph::Certificate> for Certificate {
+    fn from(c: trust_graph::Certificate) -> Self {
+        let chain: Vec<Trust> = c.chain.into_iter().map(|t| t.into()).collect();
         return Certificate { chain };
     }
 }
@@ -26,8 +25,8 @@ pub struct Trust {
     pub issued_at: u64,
 }
 
-impl From<TGTrust> for Trust {
-    fn from(t: TGTrust) -> Self {
+impl From<trust_graph::Trust> for Trust {
+    fn from(t: trust_graph::Trust) -> Self {
         let issued_for = bs58::encode(t.issued_for.to_bytes()).into_string();
         let signature = bs58::encode(t.signature.to_bytes()).into_string();
         let expires_at = t.expires_at.as_secs();
diff --git a/bin/src/main.rs b/wasm/src/main.rs
similarity index 95%
rename from bin/src/main.rs
rename to wasm/src/main.rs
index 6152877..2b1848b 100644
--- a/bin/src/main.rs
+++ b/wasm/src/main.rs
@@ -1,6 +1,6 @@
 use fluence::WasmLoggerBuilder;
 
-mod proxy_structs;
+mod dto;
 mod results;
 mod service_api;
 mod storage_impl;
diff --git a/bin/src/results.rs b/wasm/src/results.rs
similarity index 97%
rename from bin/src/results.rs
rename to wasm/src/results.rs
index 714d6d5..fa8cdee 100644
--- a/bin/src/results.rs
+++ b/wasm/src/results.rs
@@ -1,4 +1,4 @@
-use crate::proxy_structs::Certificate;
+use crate::dto::Certificate;
 use fluence::fce;
 
 #[fce]
diff --git a/bin/src/service_api.rs b/wasm/src/service_api.rs
similarity index 84%
rename from bin/src/service_api.rs
rename to wasm/src/service_api.rs
index b0868a3..9ac8de7 100644
--- a/bin/src/service_api.rs
+++ b/wasm/src/service_api.rs
@@ -1,17 +1,16 @@
-use crate::proxy_structs::Certificate;
+use crate::dto::Certificate;
 use crate::results::{AllCertsResult, InsertResult, WeightResult};
 use crate::storage_impl::get_data;
 use fluence::fce;
 use fluence_identity::{KeyPair, PublicKey};
-use std::convert::{From, Into};
-use std::fmt::Display;
+use std::convert::Into;
 use std::str::FromStr;
 use std::time::Duration;
-use trust_graph::Certificate as TGCertificate;
 
 fn insert_cert_impl(certificate: String, duration: u64) -> Result<(), String> {
     let duration = Duration::from_millis(duration);
-    let certificate = TGCertificate::from_str(&certificate)?;
+    let certificate =
+        trust_graph::Certificate::from_str(&certificate).map_err(|e| format!("{}", e))?;
 
     let mut tg = get_data().lock();
     tg.add(certificate, duration)?;
@@ -25,7 +24,7 @@ fn insert_cert(certificate: String, duration: u64) -> InsertResult {
 }
 
 fn get_weight_impl(public_key: String) -> Result<Option<u32>, String> {
-    let mut tg = get_data().lock();
+    let tg = get_data().lock();
 
     let public_key = string_to_public_key(public_key)?;
 
@@ -49,12 +48,13 @@ fn string_to_public_key(public_key: String) -> Result<PublicKey, String> {
     Ok(public_key)
 }
 
+#[fce]
 fn get_all_certs(issued_for: String) -> AllCertsResult {
     get_all_certs_impl(issued_for).into()
 }
 
 fn get_all_certs_impl(issued_for: String) -> Result<Vec<Certificate>, String> {
-    let mut tg = get_data().lock();
+    let tg = get_data().lock();
 
     let public_key = string_to_public_key(issued_for)?;
     let certs = tg.get_all_certs(public_key, &[])?;
@@ -72,7 +72,12 @@ fn test() -> String {
     let expires_at = Duration::new(15, 15);
     let issued_at = Duration::new(5, 5);
 
-    let cert = TGCertificate::issue_root(&root_kp, second_kp.public_key(), expires_at, issued_at);
+    let cert = trust_graph::Certificate::issue_root(
+        &root_kp,
+        second_kp.public_key(),
+        expires_at,
+        issued_at,
+    );
     tg.add_root_weight(root_kp.public().into(), 0).unwrap();
     tg.add_root_weight(root_kp2.public().into(), 1).unwrap();
     tg.add(cert, Duration::new(10, 10)).unwrap();
diff --git a/bin/src/storage_impl.rs b/wasm/src/storage_impl.rs
similarity index 71%
rename from bin/src/storage_impl.rs
rename to wasm/src/storage_impl.rs
index 256ff36..5176e33 100644
--- a/bin/src/storage_impl.rs
+++ b/wasm/src/storage_impl.rs
@@ -2,8 +2,9 @@
 // check if trust is already in list before adding
 // if there is an older trust - don't add received trust
 
-use crate::storage_impl::SqliteStorageError::{
-    ConvertionError, DecodeError, EncodeError, RevokeError, SqliteError, Unexpected,
+use crate::storage_impl::SQLiteStorageError::{
+    DecodeError, EncodeError, PublcKeyNotFound, PublicKeyConversion, PublicKeyFromStr, SQLiteError,
+    TrustNodeConversion, WeightConversionDB,
 };
 use core::convert::TryFrom;
 use fce_sqlite_connector;
@@ -23,9 +24,9 @@ use trust_graph::{
     Auth, PublicKeyHashable, Revoke, Storage, StorageError, TrustGraph, TrustNode, Weight,
 };
 
-static INSTANCE: OnceCell<Mutex<TrustGraph<SqliteStorage>>> = OnceCell::new();
+static INSTANCE: OnceCell<Mutex<TrustGraph<SQLiteStorage>>> = OnceCell::new();
 
-pub fn get_data() -> &'static Mutex<TrustGraph<SqliteStorage>> {
+pub fn get_data() -> &'static Mutex<TrustGraph<SQLiteStorage>> {
     INSTANCE.get_or_init(|| {
         let db_path = "/tmp/users123123.sqlite";
         let connection = fce_sqlite_connector::open(db_path).unwrap();
@@ -41,64 +42,68 @@ pub fn get_data() -> &'static Mutex<TrustGraph<SqliteStorage>> {
 
         connection.execute(init_sql).expect("cannot connect to db");
 
-        Mutex::new(TrustGraph::new(Box::new(SqliteStorage::new(connection))))
+        Mutex::new(TrustGraph::new(Box::new(SQLiteStorage::new(connection))))
     })
 }
 
-pub struct SqliteStorage {
+pub struct SQLiteStorage {
     connection: Connection,
 }
 
-impl SqliteStorage {
-    pub fn new(connection: Connection) -> SqliteStorage {
-        SqliteStorage { connection }
+impl SQLiteStorage {
+    pub fn new(connection: Connection) -> SQLiteStorage {
+        SQLiteStorage { connection }
     }
 }
 
 #[derive(ThisError, Debug)]
-pub enum SqliteStorageError {
-    #[error("Unexpected: {0}")]
-    Unexpected(String),
+pub enum SQLiteStorageError {
     #[error("{0}")]
-    SqliteError(InternalSqliteError),
+    SQLiteError(InternalSqliteError),
     #[error("{0}")]
-    EncodeError(String),
+    PublicKeyFromStr(String),
     #[error("{0}")]
-    DecodeError(String),
-    #[error("There is no entry for {0}")]
-    ConvertionError(String),
-    #[error("Cannot revoke a trust: {0}")]
-    RevokeError(String),
+    EncodeError(RmpEncodeError),
+    #[error("{0}")]
+    DecodeError(RmpDecodeError),
+    #[error("Cannot convert weight as integer from DB")]
+    WeightConversionDB,
+    #[error("Cannot convert public key as binary from DB")]
+    PublicKeyConversion,
+    #[error("Cannot convert trust node as binary from DB")]
+    TrustNodeConversion,
+    #[error("Cannot revoke. There is no trust with such PublicKey")]
+    PublcKeyNotFound,
 }
 
-impl From<InternalSqliteError> for SqliteStorageError {
+impl From<InternalSqliteError> for SQLiteStorageError {
     fn from(err: InternalSqliteError) -> Self {
-        SqliteError(err)
+        SQLiteError(err)
     }
 }
 
-impl From<RmpEncodeError> for SqliteStorageError {
+impl From<RmpEncodeError> for SQLiteStorageError {
     fn from(err: RmpEncodeError) -> Self {
-        EncodeError(format!("{}", err))
+        EncodeError(err)
     }
 }
 
-impl From<RmpDecodeError> for SqliteStorageError {
+impl From<RmpDecodeError> for SQLiteStorageError {
     fn from(err: RmpDecodeError) -> Self {
-        DecodeError(format!("{}", err))
+        DecodeError(err)
     }
 }
 
-impl From<SqliteStorageError> for String {
-    fn from(err: SqliteStorageError) -> Self {
+impl From<SQLiteStorageError> for String {
+    fn from(err: SQLiteStorageError) -> Self {
         err.into()
     }
 }
 
-impl StorageError for SqliteStorageError {}
+impl StorageError for SQLiteStorageError {}
 
-impl Storage for SqliteStorage {
-    type Error = SqliteStorageError;
+impl Storage for SQLiteStorage {
+    type Error = SQLiteStorageError;
 
     fn get(&self, pk: &PublicKeyHashable) -> Result<Option<TrustNode>, Self::Error> {
         let mut cursor = self
@@ -111,9 +116,7 @@ impl Storage for SqliteStorage {
         match cursor.next().unwrap() {
             Some(r) => {
                 log::info!("row: {:?}", r);
-                let tn_bin: &[u8] = r[0].as_binary().ok_or(ConvertionError(
-                    "cannot get trustnode as binary".to_string(),
-                ))?;
+                let tn_bin: &[u8] = r[0].as_binary().ok_or(TrustNodeConversion)?;
 
                 log::info!("binary: {:?}", tn_bin);
 
@@ -155,12 +158,8 @@ impl Storage for SqliteStorage {
         if let Some(row) = cursor.next()? {
             log::info!("row: {:?}", row);
 
-            let w = u32::try_from(
-                row[1]
-                    .as_integer()
-                    .ok_or(ConvertionError("cannot get weight as integer".to_string()))?,
-            )
-            .map_err(|e| Unexpected(format!("Unexpected. Cannot convert weight to u32: {}", e)))?;
+            let w = u32::try_from(row[1].as_integer().ok_or(WeightConversionDB)?)
+                .map_err(|_e| WeightConversionDB)?;
 
             Ok(Some(w))
         } else {
@@ -198,11 +197,9 @@ impl Storage for SqliteStorage {
 
         while let Some(row) = cursor.next()? {
             log::info!("row: {:?}", row);
-            let pk = row[0].as_string().ok_or(ConvertionError(
-                "cannot get public key as binary".to_string(),
-            ))?;
+            let pk = row[0].as_string().ok_or(PublicKeyConversion)?;
             let pk: PublicKeyHashable =
-                PublicKeyHashable::from_str(pk).map_err(|e| DecodeError(e.to_string()))?;
+                PublicKeyHashable::from_str(pk).map_err(|e| PublicKeyFromStr(e.to_string()))?;
 
             roots.push(pk)
         }
@@ -217,9 +214,7 @@ impl Storage for SqliteStorage {
                 self.insert(pk.clone(), trust_node)?;
                 Ok(())
             }
-            None => Err(RevokeError(
-                "There is no trust with such PublicKey".to_string(),
-            )),
+            None => Err(PublcKeyNotFound),
         }
     }