diff --git a/src/docker_client.rs b/src/docker_client.rs
index 5f6c635..98975cd 100644
--- a/src/docker_client.rs
+++ b/src/docker_client.rs
@@ -5,16 +5,23 @@ pub struct DockerClient {}
 impl DockerClient {
     pub fn build_image(
         ruby_version: &str,
-        rails_version: &str,
+        maybe_rails_version: Option<&str>,
         user_id: Option<u32>,
         group_id: Option<u32>,
+        rebuild: bool,
     ) -> Command {
         let mut command = Command::new("docker");
 
         command.arg("build");
 
+        if rebuild {
+            command.arg("--no-cache");
+        }
+
         Self::set_build_arg(&mut command, "RUBY_VERSION", ruby_version);
-        Self::set_build_arg(&mut command, "RAILS_VERSION", rails_version);
+        if let Some(rails_version) = maybe_rails_version {
+            Self::set_build_arg(&mut command, "RAILS_VERSION", rails_version);
+        }
 
         if let Some(id) = user_id {
             Self::set_build_arg(&mut command, "USER_ID", &id.to_string())
@@ -25,14 +32,18 @@ impl DockerClient {
 
         command.arg("-t");
 
-        Self::set_image_name(&mut command, ruby_version, rails_version);
+        Self::set_image_name(&mut command, ruby_version, maybe_rails_version);
 
         command.arg("-").stdin(Stdio::piped());
 
         command
     }
 
-    pub fn run_image(ruby_version: &str, rails_version: &str, args: Vec<String>) -> Command {
+    pub fn run_image(
+        ruby_version: &str,
+        rails_version: Option<&str>,
+        args: Vec<String>,
+    ) -> Command {
         let mut command = Self::run();
 
         Self::set_workdir(&mut command);
@@ -42,7 +53,7 @@ impl DockerClient {
         command
     }
 
-    pub fn get_help(ruby_version: &str, rails_version: &str) -> Command {
+    pub fn get_help(ruby_version: &str, rails_version: Option<&str>) -> Command {
         let mut command = Self::run();
 
         Self::set_image_name(&mut command, ruby_version, rails_version);
@@ -76,8 +87,16 @@ impl DockerClient {
             .args(["-w", current_dir]);
     }
 
-    fn set_image_name(command: &mut Command, ruby_version: &str, rails_version: &str) {
-        command.arg(format!("rails-new-{}-{}", ruby_version, rails_version));
+    fn set_image_name(
+        command: &mut Command,
+        ruby_version: &str,
+        maybe_rails_version: Option<&str>,
+    ) {
+        if let Some(rails_version) = maybe_rails_version {
+            command.arg(format!("rails-new-{}-{}", ruby_version, rails_version));
+        } else {
+            command.arg(format!("rails-new-{}", ruby_version));
+        }
     }
 
     fn set_rails_new(command: &mut Command, args: Vec<String>) {
@@ -116,7 +135,7 @@ mod tests {
 
     #[test]
     fn build_image() {
-        let command = DockerClient::build_image("3.2.3", "7.1.3", None, None);
+        let command = DockerClient::build_image("3.2.3", Some("7.1.3"), None, None, false);
 
         assert_eq!(command.get_program(), "docker");
 
@@ -139,7 +158,7 @@ mod tests {
 
     #[test]
     fn build_image_with_user_id() {
-        let command = DockerClient::build_image("3.2.3", "7.1.3", Some(1000), None);
+        let command = DockerClient::build_image("3.2.3", Some("7.1.3"), Some(1000), None, false);
 
         assert_eq!(command.get_program(), "docker");
 
@@ -164,7 +183,7 @@ mod tests {
 
     #[test]
     fn build_image_with_group_id() {
-        let command = DockerClient::build_image("3.2.3", "7.1.3", None, Some(1000));
+        let command = DockerClient::build_image("3.2.3", Some("7.1.3"), None, Some(1000), false);
 
         assert_eq!(command.get_program(), "docker");
 
@@ -187,9 +206,75 @@ mod tests {
         );
     }
 
+    #[test]
+    fn build_image_with_rebuild_flag() {
+        let command = DockerClient::build_image("3.2.3", Some("7.1.3"), None, None, true);
+
+        let args: Vec<&OsStr> = command.get_args().collect();
+
+        assert_eq!(
+            args,
+            &[
+                "build",
+                "--no-cache",
+                "--build-arg",
+                "RUBY_VERSION=3.2.3",
+                "--build-arg",
+                "RAILS_VERSION=7.1.3",
+                "-t",
+                "rails-new-3.2.3-7.1.3",
+                "-",
+            ]
+        );
+    }
+
+    #[test]
+    fn build_image_without_rails_version() {
+        let command = DockerClient::build_image("3.2.3", None, None, None, false);
+
+        let args: Vec<&OsStr> = command.get_args().collect();
+
+        assert_eq!(
+            args,
+            &[
+                "build",
+                "--build-arg",
+                "RUBY_VERSION=3.2.3",
+                "-t",
+                "rails-new-3.2.3",
+                "-",
+            ]
+        );
+    }
+
+    #[test]
+    fn build_image_with_both_ids() {
+        let command = DockerClient::build_image("3.2.3", Some("7.1.3"), Some(1000), Some(1000), false);
+
+        let args: Vec<&OsStr> = command.get_args().collect();
+
+        assert_eq!(
+            args,
+            &[
+                "build",
+                "--build-arg",
+                "RUBY_VERSION=3.2.3",
+                "--build-arg",
+                "RAILS_VERSION=7.1.3",
+                "--build-arg",
+                "USER_ID=1000",
+                "--build-arg",
+                "GROUP_ID=1000",
+                "-t",
+                "rails-new-3.2.3-7.1.3",
+                "-",
+            ]
+        );
+    }
+
     #[test]
     fn run_image() {
-        let command = DockerClient::run_image("3.2.3", "7.1.3", vec!["my_app".to_string()]);
+        let command = DockerClient::run_image("3.2.3", Some("7.1.3"), vec!["my_app".to_string()]);
 
         assert_eq!(command.get_program(), "docker");
 
@@ -216,9 +301,36 @@ mod tests {
         );
     }
 
+    #[test]
+    fn run_image_without_rails_version() {
+        let command = DockerClient::run_image("3.2.3", None, vec!["my_app".to_string()]);
+
+        let binding = current_dir().unwrap();
+        let absolute_path = canonicalize_os_path(&binding).unwrap();
+        let current_dir = absolute_path.to_str().unwrap();
+
+        let args: Vec<&OsStr> = command.get_args().collect();
+
+        assert_eq!(
+            args,
+            &[
+                "run",
+                "--rm",
+                "-v",
+                &format!("{}:{}", current_dir, current_dir),
+                "-w",
+                current_dir,
+                "rails-new-3.2.3",
+                "rails",
+                "new",
+                "my_app",
+            ]
+        );
+    }
+
     #[test]
     fn get_help() {
-        let command = DockerClient::get_help("3.2.3", "7.1.3");
+        let command = DockerClient::get_help("3.2.3", Some("7.1.3"));
 
         assert_eq!(command.get_program(), "docker");
 
diff --git a/src/main.rs b/src/main.rs
index a753532..d32f260 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -18,15 +18,17 @@ fn main() {
     let cli = Cli::parse();
 
     let ruby_version = cli.ruby_version;
-    let rails_version = cli.rails_version;
+    let rails_version = cli.rails_version.as_deref();
+    let rebuild = cli.rebuild;
 
     // Run docker build --build-arg RUBY_VERSION=$RUBY_VERSION --build-arg RAILS_VERSION=$RAILS_VERSION -t rails-new-$RUBY_VERSION-$RAILS_VERSION
     // passing the content of DOCKERFILE to the command stdin
     let mut child = DockerClient::build_image(
         &ruby_version,
-        &rails_version,
+        rails_version,
         os_specific::get_user_id(),
         os_specific::get_group_id(),
+        rebuild,
     )
     .spawn()
     .expect("Failed to execute process");
@@ -44,12 +46,12 @@ fn main() {
 
     match &cli.command {
         Some(Commands::RailsHelp {}) => {
-            command = DockerClient::get_help(&ruby_version, &rails_version)
+            command = DockerClient::get_help(&ruby_version, rails_version)
         }
 
         None => {
             // Run the image with docker run -v $(pwd):/$(pwd) -w $(pwd) rails-new-$RUBY_VERSION-$RAILS_VERSION rails new $@
-            command = DockerClient::run_image(&ruby_version, &rails_version, cli.args)
+            command = DockerClient::run_image(&ruby_version, rails_version, cli.args)
         }
     }
 
diff --git a/src/rails_new.rs b/src/rails_new.rs
index bc7a27e..1c452ac 100644
--- a/src/rails_new.rs
+++ b/src/rails_new.rs
@@ -6,10 +6,12 @@ pub struct Cli {
     #[clap(trailing_var_arg = true, required = true)]
     /// arguments passed to `rails new`
     pub args: Vec<String>,
-    #[clap(long, short = 'u', default_value = "3.4.1")]
+    #[clap(long, short = 'u', default_value = "latest")]
     pub ruby_version: String,
-    #[clap(long, short = 'r', default_value = "8.0.1")]
-    pub rails_version: String,
+    #[clap(long, short = 'r')]
+    pub rails_version: Option<String>,
+    #[clap(long)]
+    pub rebuild: bool,
 
     #[command(subcommand)]
     pub command: Option<Commands>,
@@ -52,10 +54,8 @@ mod tests {
         let m = Cli::command().get_matches_from(vec!["rails-new", "my_app"]);
 
         let ruby_version = m.get_one::<String>("ruby_version").unwrap();
-        let rails_version = m.get_one::<String>("rails_version").unwrap();
 
-        assert_eq!(ruby_version, "3.4.1");
-        assert_eq!(rails_version, "8.0.1");
+        assert_eq!(ruby_version, "latest");
 
         Ok(())
     }
@@ -73,4 +73,52 @@ mod tests {
 
         Ok(())
     }
+
+    #[test]
+    fn custom_ruby_version() -> Result<(), Box<dyn std::error::Error>> {
+        use clap::CommandFactory;
+
+        let m = Cli::command().get_matches_from(vec!["rails-new", "--ruby-version", "3.2.0", "my_app"]);
+        let ruby_version = m.get_one::<String>("ruby_version").unwrap();
+        assert_eq!(ruby_version, "3.2.0");
+
+        // Test short form
+        let m = Cli::command().get_matches_from(vec!["rails-new", "-u", "3.2.0", "my_app"]);
+        let ruby_version = m.get_one::<String>("ruby_version").unwrap();
+        assert_eq!(ruby_version, "3.2.0");
+
+        Ok(())
+    }
+
+    #[test]
+    fn rails_version_flag() -> Result<(), Box<dyn std::error::Error>> {
+        use clap::CommandFactory;
+
+        let m = Cli::command().get_matches_from(vec!["rails-new", "--rails-version", "7.1.0", "my_app"]);
+        let rails_version = m.get_one::<String>("rails_version").unwrap();
+        assert_eq!(rails_version, "7.1.0");
+
+        // Test short form
+        let m = Cli::command().get_matches_from(vec!["rails-new", "-r", "7.1.0", "my_app"]);
+        let rails_version = m.get_one::<String>("rails_version").unwrap();
+        assert_eq!(rails_version, "7.1.0");
+
+        Ok(())
+    }
+
+    #[test]
+    fn rebuild_flag() -> Result<(), Box<dyn std::error::Error>> {
+        use clap::CommandFactory;
+
+        let m = Cli::command().get_matches_from(vec!["rails-new", "--rebuild", "my_app"]);
+        let rebuild = m.get_flag("rebuild");
+        assert!(rebuild);
+
+        // Test default value (false)
+        let m = Cli::command().get_matches_from(vec!["rails-new", "my_app"]);
+        let rebuild = m.get_flag("rebuild");
+        assert!(!rebuild);
+
+        Ok(())
+    }
 }