diff --git a/Cargo.lock b/Cargo.lock
index 1861317..b7c8845 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -145,6 +145,7 @@ name = "mfm_core"
 version = "0.1.0"
 dependencies = [
  "serde",
+ "zeroize",
 ]
 
 [[package]]
@@ -587,3 +588,9 @@ dependencies = [
  "quote",
  "syn 2.0.39",
 ]
+
+[[package]]
+name = "zeroize"
+version = "1.7.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "525b4ec142c6b68a2d10f01f7bbf6755599ca3f81ea53b8431b7dd348f5fdb2d"
diff --git a/mfm_core/Cargo.toml b/mfm_core/Cargo.toml
index c8f2b8e..5a78158 100644
--- a/mfm_core/Cargo.toml
+++ b/mfm_core/Cargo.toml
@@ -7,3 +7,4 @@ edition = "2021"
 
 [dependencies]
 serde = "1.0.193"
+zeroize = "1.7.0"
diff --git a/mfm_core/src/config/authentication/mod.rs b/mfm_core/src/config/authentication/mod.rs
new file mode 100644
index 0000000..d29a03d
--- /dev/null
+++ b/mfm_core/src/config/authentication/mod.rs
@@ -0,0 +1,15 @@
+pub mod wallet;
+
+use serde::{Deserialize, Serialize};
+
+use self::wallet::Wallet;
+
+#[derive(Clone, Debug, PartialEq, Eq, Serialize, Deserialize)]
+#[serde(rename_all = "snake_case", tag = "type")]
+pub enum Method {
+    Wallet(Wallet),
+    MetaMask, // TODO: the next auth method
+}
+
+#[derive(Clone, Debug, PartialEq, Eq, Deserialize, Serialize)]
+pub struct Methods(Vec<Method>);
diff --git a/mfm_core/src/config/authentication/wallet.rs b/mfm_core/src/config/authentication/wallet.rs
new file mode 100644
index 0000000..90bd738
--- /dev/null
+++ b/mfm_core/src/config/authentication/wallet.rs
@@ -0,0 +1,11 @@
+use serde::{Deserialize, Serialize};
+
+use crate::password::{deserialize_safe_password, SafePassword};
+
+#[derive(Clone, Debug, PartialEq, Eq, Serialize, Deserialize)]
+pub struct Wallet {
+    #[serde(deserialize_with = "deserialize_safe_password")]
+    pub private_key: SafePassword,
+    pub not_encrypted: bool,
+    pub env_password: Option<String>,
+}
diff --git a/mfm_core/src/config/dexes.rs b/mfm_core/src/config/dexes.rs
new file mode 100644
index 0000000..f5a0d23
--- /dev/null
+++ b/mfm_core/src/config/dexes.rs
@@ -0,0 +1,27 @@
+use serde::{Deserialize, Serialize};
+use std::collections::HashMap;
+
+#[derive(Clone, Debug, PartialEq, Eq, Deserialize, Serialize)]
+pub enum Kind {
+    UniswapV2,
+}
+
+#[derive(Clone, Debug, PartialEq, Eq, Deserialize, Serialize)]
+pub struct Dex {
+    pub name: String,
+    pub kind: Kind,
+    pub router_address: String,
+    pub factory_address: String,
+    pub network_id: String,
+}
+
+#[derive(Clone, Debug, PartialEq, Eq, Deserialize, Serialize)]
+pub struct Dexes(HashMap<String, Dex>);
+impl Dexes {
+    pub fn hashmap(&self) -> &HashMap<String, Dex> {
+        &self.0
+    }
+    pub fn get(&self, key: &str) -> Option<&Dex> {
+        self.0.get(key)
+    }
+}
diff --git a/mfm_core/src/config/mod.rs b/mfm_core/src/config/mod.rs
index 2c7f786..78f947f 100644
--- a/mfm_core/src/config/mod.rs
+++ b/mfm_core/src/config/mod.rs
@@ -1,88 +1,20 @@
 use serde::{Deserialize, Serialize};
-use std::collections::HashMap;
 
-#[derive(Clone, Debug, PartialEq, Eq, Deserialize, Serialize)]
-pub enum Kind {
-    EVM,
-}
-
-#[derive(Clone, Debug, PartialEq, Deserialize, Serialize)]
-pub struct Network {
-    pub name: String,
-    pub kind: Kind,
-    pub symbol: String,
-    pub decimals: Option<u8>,
-    pub chain_id: u32,
-    pub node_url: String,
-    pub node_url_failover: Option<String>,
-    pub blockexplorer_url: Option<String>,
-    pub min_balance_coin: f64,
-    pub wrapped_asset: Option<Token>,
-}
-
-#[derive(Clone, Debug, PartialEq, Deserialize, Serialize)]
-pub struct Networks(HashMap<String, Network>);
-impl Networks {
-    pub fn get(&self, key: &str) -> Option<&Network> {
-        self.0.get(key)
-    }
-    pub fn hashmap(&self) -> &HashMap<String, Network> {
-        &self.0
-    }
-}
-
-#[derive(Clone, Debug, PartialEq, Eq, Deserialize, Serialize)]
-pub struct Dex {
-    pub name: String,
-    pub kind: Kind,
-    pub router_address: String,
-    pub factory_address: String,
-    pub network_id: String,
-}
-
-#[derive(Clone, Debug, PartialEq, Eq, Deserialize, Serialize)]
-pub struct Dexes(HashMap<String, Dex>);
-impl Dexes {
-    pub fn hashmap(&self) -> &HashMap<String, Dex> {
-        &self.0
-    }
-    pub fn get(&self, key: &str) -> Option<&Dex> {
-        self.0.get(key)
-    }
-}
+pub mod authentication;
+pub mod dexes;
+pub mod network;
+pub mod token;
 
-#[derive(Clone, Debug, PartialEq, Deserialize, Serialize)]
-pub struct TokenNetwork {
-    pub(crate) name: String,
-    pub(crate) network_id: String,
-    pub(crate) address: String,
-    pub(crate) slippage: f64,
-    pub(crate) path_asset: String,
-}
-
-#[derive(Clone, Debug, PartialEq, Deserialize, Serialize)]
-pub struct TokenNetworks(HashMap<String, TokenNetwork>);
+use dexes::Dexes;
+use network::Networks;
+use token::Tokens;
 
-#[derive(Clone, Debug, PartialEq, Deserialize, Serialize)]
-pub struct Token {
-    pub(crate) kind: String,
-    pub(crate) networks: TokenNetworks,
-}
+use self::authentication::Methods;
 
 #[derive(Clone, Debug, PartialEq, Deserialize, Serialize)]
-pub struct Tokens(HashMap<String, Token>);
-impl Tokens {
-    pub fn hashmap(&self) -> &HashMap<String, Token> {
-        &self.0
-    }
-
-    pub fn get(&self, key: &str) -> Option<&Token> {
-        self.0.get(key)
-    }
-}
-
 pub struct Config {
     pub networks: Networks,
     pub dexes: Dexes,
     pub tokens: Tokens,
+    pub auth_methods: Methods,
 }
diff --git a/mfm_core/src/config/network.rs b/mfm_core/src/config/network.rs
new file mode 100644
index 0000000..0249fe1
--- /dev/null
+++ b/mfm_core/src/config/network.rs
@@ -0,0 +1,33 @@
+use super::token::Token;
+use serde::{Deserialize, Serialize};
+use std::collections::HashMap;
+
+#[derive(Clone, Debug, PartialEq, Eq, Deserialize, Serialize)]
+pub enum Kind {
+    EVM,
+}
+
+#[derive(Clone, Debug, PartialEq, Deserialize, Serialize)]
+pub struct Network {
+    pub name: String,
+    pub kind: Kind,
+    pub symbol: String,
+    pub decimals: Option<u8>,
+    pub chain_id: u32,
+    pub node_url: String,
+    pub node_url_failover: Option<String>,
+    pub blockexplorer_url: Option<String>,
+    pub min_balance_coin: f64,
+    pub wrapped_asset: Option<Token>,
+}
+
+#[derive(Clone, Debug, PartialEq, Deserialize, Serialize)]
+pub struct Networks(HashMap<String, Network>);
+impl Networks {
+    pub fn get(&self, key: &str) -> Option<&Network> {
+        self.0.get(key)
+    }
+    pub fn hashmap(&self) -> &HashMap<String, Network> {
+        &self.0
+    }
+}
diff --git a/mfm_core/src/config/token.rs b/mfm_core/src/config/token.rs
new file mode 100644
index 0000000..45a222a
--- /dev/null
+++ b/mfm_core/src/config/token.rs
@@ -0,0 +1,37 @@
+use serde::{Deserialize, Serialize};
+use std::collections::HashMap;
+
+#[derive(Clone, Debug, PartialEq, Eq, Deserialize, Serialize)]
+pub enum Kind {
+    ERC20,
+}
+
+#[derive(Clone, Debug, PartialEq, Deserialize, Serialize)]
+pub struct TokenNetwork {
+    pub name: String,
+    pub network_id: String,
+    pub address: String,
+    pub slippage: f64,
+    pub path_asset: String,
+}
+
+#[derive(Clone, Debug, PartialEq, Deserialize, Serialize)]
+pub struct TokenNetworks(HashMap<String, TokenNetwork>);
+
+#[derive(Clone, Debug, PartialEq, Deserialize, Serialize)]
+pub struct Token {
+    pub kind: Kind,
+    pub networks: TokenNetworks,
+}
+
+#[derive(Clone, Debug, PartialEq, Deserialize, Serialize)]
+pub struct Tokens(HashMap<String, Token>);
+impl Tokens {
+    pub fn hashmap(&self) -> &HashMap<String, Token> {
+        &self.0
+    }
+
+    pub fn get(&self, key: &str) -> Option<&Token> {
+        self.0.get(key)
+    }
+}
diff --git a/mfm_core/src/hidden/mod.rs b/mfm_core/src/hidden/mod.rs
new file mode 100644
index 0000000..4add6a6
--- /dev/null
+++ b/mfm_core/src/hidden/mod.rs
@@ -0,0 +1,72 @@
+/// ! A wrapper to conceal secrets when output into logs or displayed.
+//
+use serde::{Deserialize, Serialize};
+use std::{fmt, ops::DerefMut};
+
+/// A simple struct with a single inner value to wrap content of any type.
+#[derive(Copy, Clone, Serialize, Deserialize)]
+#[serde(transparent)]
+pub struct Hidden<T> {
+    inner: T,
+}
+
+impl<T> Hidden<T> {
+    /// Returns ownership of the inner value discarding the wrapper.
+    pub fn into_inner(self) -> T {
+        self.inner
+    }
+}
+
+impl<T> From<T> for Hidden<T> {
+    fn from(inner: T) -> Self {
+        Hidden { inner }
+    }
+}
+
+/// Defines a masked value for the type to output as debug information. Concealing the secrets within.
+impl<T> fmt::Debug for Hidden<T> {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        write!(f, "Hidden<{}>", std::any::type_name::<T>())
+    }
+}
+
+/// Defines a masked value for the type to display. Concealing the secrets within.
+impl<T> fmt::Display for Hidden<T> {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        write!(f, "Hidden<{}>", std::any::type_name::<T>())
+    }
+}
+
+/// Attempts to make the wrapper more transparent by having deref return a reference to the inner value.
+impl<T> std::ops::Deref for Hidden<T> {
+    type Target = T;
+
+    fn deref(&self) -> &Self::Target {
+        &self.inner
+    }
+}
+
+impl<T> DerefMut for Hidden<T> {
+    fn deref_mut(&mut self) -> &mut Self::Target {
+        &mut self.inner
+    }
+}
+
+impl<T: PartialEq> PartialEq for Hidden<T> {
+    fn eq(&self, other: &Self) -> bool {
+        self.inner == other.inner
+    }
+}
+
+impl<T: Eq> Eq for Hidden<T> {}
+
+#[cfg(test)]
+mod test {
+    use super::*;
+
+    #[test]
+    fn into_applies_wrapper_deref_removes_it() {
+        let wrapped: Hidden<u8> = 42.into();
+        assert_eq!(42, *wrapped)
+    }
+}
diff --git a/mfm_core/src/lib.rs b/mfm_core/src/lib.rs
index e489ce0..d81e21f 100644
--- a/mfm_core/src/lib.rs
+++ b/mfm_core/src/lib.rs
@@ -1,4 +1,6 @@
 pub mod config;
+pub mod hidden;
+pub mod password;
 pub mod states;
 pub mod tasks;
 
diff --git a/mfm_core/src/password/mod.rs b/mfm_core/src/password/mod.rs
new file mode 100644
index 0000000..b521668
--- /dev/null
+++ b/mfm_core/src/password/mod.rs
@@ -0,0 +1,59 @@
+use crate::hidden::Hidden;
+use serde::{Deserialize, Serialize};
+use std::{error::Error, fmt, str::FromStr};
+use zeroize::Zeroize;
+
+#[derive(Clone, Debug, Serialize, Deserialize, PartialEq, Eq)]
+#[serde(transparent)]
+pub struct SafePassword {
+    password: Hidden<Box<[u8]>>,
+}
+
+impl From<String> for SafePassword {
+    fn from(s: String) -> Self {
+        Self {
+            password: Hidden::from(s.into_bytes().into_boxed_slice()),
+        }
+    }
+}
+
+impl Drop for SafePassword {
+    fn drop(&mut self) {
+        self.password.zeroize();
+    }
+}
+
+impl SafePassword {
+    /// Gets a reference to bytes of a passphrase.
+    pub fn reveal(&self) -> &[u8] {
+        self.password.as_ref()
+    }
+}
+
+/// An error for parsing a password from string.
+#[derive(Debug)]
+pub struct PasswordError;
+
+impl Error for PasswordError {}
+
+impl fmt::Display for PasswordError {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        write!(f, "PasswordError")
+    }
+}
+
+impl FromStr for SafePassword {
+    type Err = PasswordError;
+
+    fn from_str(s: &str) -> Result<Self, Self::Err> {
+        Ok(Self::from(s.to_owned()))
+    }
+}
+
+pub fn deserialize_safe_password<'de, D>(deserializer: D) -> Result<SafePassword, D::Error>
+where
+    D: serde::Deserializer<'de>,
+{
+    let password: String = Deserialize::deserialize(deserializer)?;
+    Ok(SafePassword::from(password))
+}