diff --git a/src/command.rs b/src/command.rs
index d013279..ac5479e 100644
--- a/src/command.rs
+++ b/src/command.rs
@@ -23,14 +23,14 @@ pub trait Command {
 }
 
 pub struct CommandSequence {
-    command: Option<Box<dyn Command>>,
+    command: Box<dyn Command>,
     next_command: Option<Box<dyn Command>>,
 }
 
 impl CommandSequence {
-    pub fn new() -> Self {
+    pub fn new(command: impl Command + 'static) -> Self {
         Self {
-            command: None,
+            command: Box::new(command),
             next_command: None,
         }
     }
@@ -47,11 +47,7 @@ impl CommandSequence {
 
 impl Command for CommandSequence {
     fn spawn(&self) -> ExitCode {
-        let mut exit_code = ExitCode::new(0);
-
-        if self.command.is_some() {
-            exit_code = self.command.as_ref().unwrap().spawn();
-        }
+        let mut exit_code = self.command.spawn();
 
         if self.next_command.is_some() {
             exit_code = self.next_command.as_ref().unwrap().spawn();
@@ -66,13 +62,8 @@ pub struct UnixProgram {
 }
 
 impl UnixProgram {
-    pub fn new() -> Self {
-        Self { argv: Vec::new() }
-    }
-
-    pub fn argv(&mut self, argv: Vec<String>) -> &mut Self {
-        self.argv = argv;
-        self
+    pub fn new(argv: Vec<String>) -> Self {
+        Self { argv }
     }
 }
 
diff --git a/src/parser.rs b/src/parser.rs
index dbdead1..a48dd30 100644
--- a/src/parser.rs
+++ b/src/parser.rs
@@ -4,8 +4,8 @@ pub fn parse_command_line(line: String) -> Option<CommandSequence> {
     let argv: Vec<String> = line.split_whitespace().map(|s| s.to_string()).collect();
 
     if !argv.is_empty() {
-        let _command = UnixProgram::new().argv(argv);
-        let command_sequence = CommandSequence::new();
+        let command = UnixProgram::new(argv);
+        let command_sequence = CommandSequence::new(command);
         // command_sequence.add(_command);
         Some(command_sequence)
     } else {