diff --git a/src/lib.rs b/src/lib.rs
index f40a0c2..419b65a 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -26,5 +26,6 @@ pub mod bookmarks;
 pub mod filetransfer;
 pub mod fs;
 pub mod host;
+pub mod system;
 pub mod ui;
 pub mod utils;
diff --git a/src/main.rs b/src/main.rs
index f41067d..afd0a06 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -40,6 +40,7 @@ mod bookmarks;
 mod filetransfer;
 mod fs;
 mod host;
+mod system;
 mod ui;
 mod utils;
 
diff --git a/src/system/bookmarks_client.rs b/src/system/bookmarks_client.rs
new file mode 100644
index 0000000..791cc92
--- /dev/null
+++ b/src/system/bookmarks_client.rs
@@ -0,0 +1,107 @@
+//! ## BookmarksClient
+//!
+//! `bookmarks_client` is the module which provides an API between the Bookmarks module and the system
+
+/*
+*
+*   Copyright (C) 2020 Christian Visintin - christian.visintin1997@gmail.com
+*
+* 	This file is part of "TermSCP"
+*
+*   TermSCP is free software: you can redistribute it and/or modify
+*   it under the terms of the GNU General Public License as published by
+*   the Free Software Foundation, either version 3 of the License, or
+*   (at your option) any later version.
+*
+*   TermSCP is distributed in the hope that it will be useful,
+*   but WITHOUT ANY WARRANTY; without even the implied warranty of
+*   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+*   GNU General Public License for more details.
+*
+*   You should have received a copy of the GNU General Public License
+*   along with TermSCP.  If not, see <http://www.gnu.org/licenses/>.
+*
+*/
+
+// Local
+use crate::bookmarks::serializer::BookmarkSerializer;
+use crate::bookmarks::{Bookmark, SerializerError, SerializerErrorKind, UserHosts};
+use crate::filetransfer::FileTransferProtocol;
+// Ext
+use std::fs::OpenOptions;
+use std::path::{Path, PathBuf};
+
+/// ## BookmarksClient
+///
+/// BookmarksClient provides a layer between the host system and the bookmarks module
+pub struct BookmarksClient {
+    pub hosts: UserHosts,
+    bookmarks_file: PathBuf,
+    key_file: PathBuf,
+}
+
+impl BookmarksClient {
+    /// ### BookmarksClient
+    ///
+    /// Instantiates a new BookmarksClient
+    /// Bookmarks file path must be provided
+    /// Key file must be provided
+    pub fn new(bookmarks_file: &Path, key_file: &Path) -> Result<BookmarksClient, SerializerError> {
+        // Create default hosts
+        let default_hosts: UserHosts = Default::default();
+        let client: BookmarksClient = BookmarksClient {
+            hosts: default_hosts,
+            bookmarks_file: PathBuf::from(bookmarks_file),
+            key_file: PathBuf::from(key_file),
+        };
+        // If bookmark file doesn't exist, initialize it
+        if !bookmarks_file.exists() {
+            if let Err(err) = client.write_bookmarks() {
+                return Err(err)
+            }
+        }
+        // If key file doesn't exist, create key
+        if !key_file.exists() {
+            if let Err(err) = client.generate_key() {
+                return Err(err)
+            }
+        }
+        Ok(client)
+    }
+
+    /// ### make_bookmark
+    /// 
+    /// Make bookmark from credentials
+    pub fn make_bookmark(&self, addr: String, port: u16, protocol: FileTransferProtocol, username: String, password: Option<String>) -> Bookmark {
+        // TODO: crypt password
+    }
+
+    /// ### write_bookmarks
+    ///
+    /// Write bookmarks to file
+    pub fn write_bookmarks(&self) -> Result<(), SerializerError> {
+        // Open file
+        match OpenOptions::new()
+            .create(true)
+            .write(true)
+            .truncate(true)
+            .open(self.bookmarks_file.as_path())
+        {
+            Ok(writer) => {
+                let serializer: BookmarkSerializer = BookmarkSerializer {};
+                serializer.serialize(Box::new(writer), &self.hosts)
+            }
+            Err(err) => Err(SerializerError::new_ex(
+                SerializerErrorKind::IoError,
+                err.to_string(),
+            )),
+        }
+    }
+
+    /// ### generate_key
+    /// 
+    /// Generate a new AES key and write it to key file
+    fn generate_key(&self) -> Result<(), SerializerError> {
+        // TODO: write
+    }
+}
diff --git a/src/system/environment.rs b/src/system/environment.rs
new file mode 100644
index 0000000..c4af3fe
--- /dev/null
+++ b/src/system/environment.rs
@@ -0,0 +1,68 @@
+//! ## Environment
+//!
+//! `environment` is the module which provides Path and values for the system environment
+
+/*
+*
+*   Copyright (C) 2020 Christian Visintin - christian.visintin1997@gmail.com
+*
+* 	This file is part of "TermSCP"
+*
+*   TermSCP is free software: you can redistribute it and/or modify
+*   it under the terms of the GNU General Public License as published by
+*   the Free Software Foundation, either version 3 of the License, or
+*   (at your option) any later version.
+*
+*   TermSCP is distributed in the hope that it will be useful,
+*   but WITHOUT ANY WARRANTY; without even the implied warranty of
+*   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+*   GNU General Public License for more details.
+*
+*   You should have received a copy of the GNU General Public License
+*   along with TermSCP.  If not, see <http://www.gnu.org/licenses/>.
+*
+*/
+
+// Deps
+extern crate dirs;
+
+// Ext
+use std::path::PathBuf;
+
+/// ### get_config_dir
+///
+/// Get termscp configuration directory path.
+/// Returns None, if it's not possible to get it
+pub fn init_config_dir() -> Result<Option<PathBuf>, String> {
+    // Get file
+    lazy_static! {
+        static ref CONF_DIR: Option<PathBuf> = dirs::config_dir();
+    }
+    if CONF_DIR.is_some() {
+        // Get path of bookmarks
+        let mut p: PathBuf = CONF_DIR.as_ref().unwrap().clone();
+        // Append termscp dir
+        p.push("termscp/");
+        // If directory doesn't exist, create it
+        match p.exists() {
+            true => Ok(Some(p)),
+            false => match std::fs::create_dir(p.as_path()) {
+                Ok(_) => Ok(Some(p)),
+                Err(err) => Err(err.to_string()),
+            },
+        }
+    } else {
+        Ok(None)
+    }
+}
+
+#[cfg(test)]
+mod tests {
+
+    use super::*;
+
+    #[test]
+    fn test_system_environment_get_config_dir() {
+        assert!(init_config_dir().ok().unwrap().is_some());
+    }
+}
diff --git a/src/system/mod.rs b/src/system/mod.rs
new file mode 100644
index 0000000..d0fe5be
--- /dev/null
+++ b/src/system/mod.rs
@@ -0,0 +1,28 @@
+//! ## System
+//!
+//! `system` is the module which contains functions and data types related to current system
+
+/*
+*
+*   Copyright (C) 2020 Christian Visintin - christian.visintin1997@gmail.com
+*
+* 	This file is part of "TermSCP"
+*
+*   TermSCP is free software: you can redistribute it and/or modify
+*   it under the terms of the GNU General Public License as published by
+*   the Free Software Foundation, either version 3 of the License, or
+*   (at your option) any later version.
+*
+*   TermSCP is distributed in the hope that it will be useful,
+*   but WITHOUT ANY WARRANTY; without even the implied warranty of
+*   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+*   GNU General Public License for more details.
+*
+*   You should have received a copy of the GNU General Public License
+*   along with TermSCP.  If not, see <http://www.gnu.org/licenses/>.
+*
+*/
+
+// modules
+pub mod bookmarks_client;
+pub mod environment;