diff --git a/Cargo.lock b/Cargo.lock
index e4e2b7e..1a6cc82 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -7,6 +7,8 @@ name = "Rshell"
 version = "0.1.0"
 dependencies = [
  "dirs",
+ "gethostname",
+ "users",
 ]
 
 [[package]]
@@ -41,6 +43,16 @@ dependencies = [
  "winapi",
 ]
 
+[[package]]
+name = "gethostname"
+version = "0.4.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8a329e22866dd78b35d2c639a4a23d7b950aeae300dfd79f4fb19f74055c2404"
+dependencies = [
+ "libc",
+ "windows",
+]
+
 [[package]]
 name = "getrandom"
 version = "0.2.8"
@@ -58,6 +70,15 @@ version = "0.2.138"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "db6d7e329c562c5dfab7a46a2afabc8b987ab9a4834c9d1ca04dc54c1546cef8"
 
+[[package]]
+name = "log"
+version = "0.4.17"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "abb12e687cfb44aa40f41fc3978ef76448f9b6038cad6aef4259d3c095a2382e"
+dependencies = [
+ "cfg-if",
+]
+
 [[package]]
 name = "proc-macro2"
 version = "1.0.47"
@@ -133,6 +154,16 @@ version = "1.0.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "6ceab39d59e4c9499d4e5a8ee0e2735b891bb7308ac83dfb4e80cad195c9f6f3"
 
+[[package]]
+name = "users"
+version = "0.11.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "24cc0f6d6f267b73e5a2cadf007ba8f9bc39c6a6f9666f8cf25ea809a153b032"
+dependencies = [
+ "libc",
+ "log",
+]
+
 [[package]]
 name = "wasi"
 version = "0.11.0+wasi-snapshot-preview1"
@@ -160,3 +191,60 @@ name = "winapi-x86_64-pc-windows-gnu"
 version = "0.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "712e227841d057c1ee1cd2fb22fa7e5a5461ae8e48fa2ca79ec42cfc1931183f"
+
+[[package]]
+name = "windows"
+version = "0.43.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "04662ed0e3e5630dfa9b26e4cb823b817f1a9addda855d973a9458c236556244"
+dependencies = [
+ "windows_aarch64_gnullvm",
+ "windows_aarch64_msvc",
+ "windows_i686_gnu",
+ "windows_i686_msvc",
+ "windows_x86_64_gnu",
+ "windows_x86_64_gnullvm",
+ "windows_x86_64_msvc",
+]
+
+[[package]]
+name = "windows_aarch64_gnullvm"
+version = "0.42.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "41d2aa71f6f0cbe00ae5167d90ef3cfe66527d6f613ca78ac8024c3ccab9a19e"
+
+[[package]]
+name = "windows_aarch64_msvc"
+version = "0.42.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "dd0f252f5a35cac83d6311b2e795981f5ee6e67eb1f9a7f64eb4500fbc4dcdb4"
+
+[[package]]
+name = "windows_i686_gnu"
+version = "0.42.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "fbeae19f6716841636c28d695375df17562ca208b2b7d0dc47635a50ae6c5de7"
+
+[[package]]
+name = "windows_i686_msvc"
+version = "0.42.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "84c12f65daa39dd2babe6e442988fc329d6243fdce47d7d2d155b8d874862246"
+
+[[package]]
+name = "windows_x86_64_gnu"
+version = "0.42.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "bf7b1b21b5362cbc318f686150e5bcea75ecedc74dd157d874d754a2ca44b0ed"
+
+[[package]]
+name = "windows_x86_64_gnullvm"
+version = "0.42.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "09d525d2ba30eeb3297665bd434a54297e4170c7f1a44cad4ef58095b4cd2028"
+
+[[package]]
+name = "windows_x86_64_msvc"
+version = "0.42.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f40009d85759725a34da6d89a94e63d7bdc50a862acf0dbc7c8e488f1edcb6f5"
diff --git a/Cargo.toml b/Cargo.toml
index 943aed5..46a0b51 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -3,7 +3,11 @@ name = "Rshell"
 version = "0.1.0"
 edition = "2021"
 
-# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+[profile.release]
+lto = true
+codegen-units = 1
 
 [dependencies]
 dirs = "4.0.0"
+users = "0.11.0"
+gethostname = "0.4.1"
diff --git a/README.md b/README.md
index b03bba0..9257bba 100644
--- a/README.md
+++ b/README.md
@@ -22,6 +22,96 @@ Later, I can even make something useful out of it. For example, I could make it
 * Add a function that gets the path of the history file, rather than copying it every time
 * Other tests for the rest of the features
 * Add a builtin history command
-* Add a test for the treat_history_callback function
 * Get some sleep
 * Order the file (modules...)
+
+# Annotated process_line
+```rust
+fn process_line(input: String) -> bool {
+
+    // must be peekable so we know when we are on the last command
+    let mut commands = input.trim().split(" | ").peekable();
+    //Will be used later, in the case of pipes
+    let mut previous_command = None;
+
+    //While have commands to process...
+    while let Some(command) = commands.next()  {
+        //First command is divided...
+        let mut parts = command.trim().split_whitespace();
+        //into a command...
+        let mut command = parts.next().unwrap();
+        //and args
+        let args = parts;
+
+        //builtins : exit and cd are special
+        match command {
+            "cd" => {
+                //If a dir is given, we use it by dereferencing
+                //otherwise it is /
+                let new_dir = args.peekable().peek().map_or("/", |x| *x);
+                let root = Path::new(new_dir);
+                if let Err(e) = env::set_current_dir(&root) {
+                    eprintln!("{}", e);
+                }
+
+                previous_command = None;
+            },
+            "exit" => return true,
+            "history" => {
+                let stdout = Stdio::inherit();
+                println!("Insert history here");
+            },
+            //not builtin: we process it
+            command => {
+                //If we are at the first command (aka previous_command is None)...
+                let stdin = previous_command.map_or(
+                        //We inherit, meaning stdin gets the stream from its parent
+                        //what I guess that means is that the child (our command)
+                        //inherits the file descriptors (stdin, stdout, stderr)
+                        //from the process of this very own rust program !
+                        Stdio::inherit(),
+                        //otherwise, our input is the output from the last command
+                        //(from converts a ChildStdOut to a Stdio)
+                        |output: Child| Stdio::from(output.stdout.unwrap())
+                    );
+
+                let stdout = if commands.peek().is_some() {
+                    // there is another command piped behind this one
+                    // prepare to send output to the next command
+                    Stdio::piped()
+                } else {
+                    // there are no more commands piped behind this one
+                    // send output to shell stdout
+                    // the child inherits from the parent's file descriptor
+                    Stdio::inherit()
+                };
+                
+                //Run the command
+                let output = Command::new(command)
+                    .args(args)
+                    .stdin(stdin)
+                    .stdout(stdout)
+                    //spawn : execute the command as a child process, returning a handle to it
+                    .spawn();
+
+                //Checking for errors
+                //If it matched, previous_command becomes the output of this to be used
+                //next loop
+                match output {
+                    Ok(output) => { previous_command = Some(output); },
+                    Err(e) => {
+                        previous_command = None;
+                        eprintln!("{}", e);
+                    },
+                };
+            }
+        }
+    }
+
+    if let Some(mut final_command) = previous_command {
+        // block until the final command has finished
+        final_command.wait();
+    }
+    return false; 
+}
+```
diff --git a/src/main.rs b/src/main.rs
index 2fa7a2d..50a9593 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -11,31 +11,25 @@ use std::fs::File;
 use std::fs::OpenOptions;
 use std::fs;
 use std::io::{self, prelude::*, BufReader};
+use users::{get_user_by_uid, get_current_uid};
+use gethostname::gethostname;
+
 
 //used for home directory
 extern crate dirs;
 
 fn process_line(input: String) -> bool {
 
-    // must be peekable so we know when we are on the last command
     let mut commands = input.trim().split(" | ").peekable();
-    //Will be used later, in the case of pipes
     let mut previous_command = None;
 
-    //While have commands to process...
     while let Some(command) = commands.next()  {
-        //First command is divided...
         let mut parts = command.trim().split_whitespace();
-        //into a command...
         let mut command = parts.next().unwrap();
-        //and args
         let args = parts;
 
-        //builtins : exit and cd are special
         match command {
             "cd" => {
-                //If a dir is given, we use it by dereferencing
-                //otherwise it is /
                 let new_dir = args.peekable().peek().map_or("/", |x| *x);
                 let root = Path::new(new_dir);
                 if let Err(e) = env::set_current_dir(&root) {
@@ -45,42 +39,28 @@ fn process_line(input: String) -> bool {
                 previous_command = None;
             },
             "exit" => return true,
-            //not builtin: we process it
+            "history" => {
+                let stdout = Stdio::inherit();
+                print_history();
+            },
             command => {
-                //If we are at the first command (aka previous_command is None)...
                 let stdin = previous_command.map_or(
-                        //We inherit, meaning stdin gets the stream from its parent
-                        //what I guess that means is that the child (our command)
-                        //inherits the file descriptors (stdin, stdout, stderr)
-                        //from the process of this very own rust program !
                         Stdio::inherit(),
-                        //otherwise, our input is the output from the last command
-                        //(from converts a ChildStdOut to a Stdio)
                         |output: Child| Stdio::from(output.stdout.unwrap())
                     );
 
                 let stdout = if commands.peek().is_some() {
-                    // there is another command piped behind this one
-                    // prepare to send output to the next command
                     Stdio::piped()
                 } else {
-                    // there are no more commands piped behind this one
-                    // send output to shell stdout
-                    // the child inherits from the parent's file descriptor
                     Stdio::inherit()
                 };
                 
-                //Run the command
                 let output = Command::new(command)
                     .args(args)
                     .stdin(stdin)
                     .stdout(stdout)
-                    //spawn : execute the command as a child process, returning a handle to it
                     .spawn();
 
-                //Checking for errors
-                //If it matched, previous_command becomes the output of this to be used
-                //next loop
                 match output {
                     Ok(output) => { previous_command = Some(output); },
                     Err(e) => {
@@ -123,11 +103,21 @@ fn get_history_number() -> Result<i32, std::io::Error> {
     let filepath = dirs::home_dir().unwrap().join("history.rshell");
     let file = File::open(filepath)?;
     let mut reader = BufReader::new(file).lines();
-    let myline = String::from(reader.last().unwrap()?);
+    let myline = String::from(reader.last().unwrap_or(Ok(String::from("1")))?);
     let mut number = myline.split(' ').next().expect("???").parse().unwrap();
     return Ok(number);
 }
 
+fn print_history() -> Result<(), std::io::Error> {
+    let filepath = dirs::home_dir().unwrap().join("history.rshell");
+    let file = File::open(filepath)?;
+    let contents = BufReader::new(file).lines();
+    for line in contents {
+        println!("{}", line.unwrap());
+    }
+    return Ok(());
+}
+
 fn get_hist_from_number(number: &i32) -> Option<String> {
     //Returns a command from its number in hist file
     let filepath = dirs::home_dir().unwrap().join("history.rshell");
@@ -159,33 +149,71 @@ fn treat_history_callback(line: &str) -> Option<String> {
     get_hist_from_number(&mynbr)
 }
 
+fn build_prompt() -> String {
+    let user = String::from(
+        get_user_by_uid(get_current_uid())
+        .unwrap()
+        .name()
+        .to_str()
+        .unwrap()
+        );
+
+    let host = String::from(
+        gethostname::gethostname()
+        .to_str()
+        .unwrap()
+        );
+
+    let current_dir = String::from(
+        env::current_dir()
+        .unwrap()
+        .to_str()
+        .unwrap()
+        );
+
+    let s = current_dir.split('/');
+    let dir_last = String::from(
+        s.last()
+        .unwrap()
+        );
+
+    let prompt = String::from(format!("[{}@{} in {}] ", user, host, dir_last));
+    return prompt;
+}
+
 
 fn main(){
     loop {
-        print!("> ");
-        //stdout().flush();
+        print!("{}", build_prompt());
+        stdout().flush();
 
         let mut input = String::new();
-        stdin().read_line(&mut input).unwrap();
-        if input.starts_with("!") {
-            let command_found = treat_history_callback(&input);
-            match command_found {
-                Some(c) => {
-                    write_to_history(&c);
-                    process_line(c);
-                },
-                None => ()
-            };
-        } else {
-            write_to_history(&input);
-            if process_line(input) {
-                return
+        let bytes = stdin().read_line(&mut input).unwrap();
+        if (bytes > 0) && (input != String::from("\n"))  {
+            if input.starts_with("!") {
+                let command_found = treat_history_callback(&input);
+                match command_found {
+                    Some(c) => {
+                        write_to_history(&c);
+                        process_line(c);
+                    },
+                    None => ()
+                };
+            } else {
+                write_to_history(&input);
+                if process_line(input) {
+                    return
+                }
             }
+        } else {
+            //Command was empty, new line
+            continue;
         }
     }
 }
 
 
+
 #[cfg(test)]
 mod tests {
     use super::*;
@@ -226,6 +254,15 @@ mod tests {
 
         assert_eq!(myline.trim(), expected.trim()); 
     }
+
+    #[test]
+    fn test_history_callback() {
+        inittests();
+        let expected = String::from("ls");
+        assert_eq!(treat_history_callback("!1"), Some(expected));
+    }
+
+
 }