diff --git a/Cargo.lock b/Cargo.lock
index bca5893..4db5574 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -104,6 +104,15 @@ version = "2.10.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d7a1e2f27636f116493b8b860f5546edb47c8d8f8ea73e1d2a20be88e28d1fea"
 
+[[package]]
+name = "erased-serde"
+version = "0.3.31"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6c138974f9d5e7fe373eb04df7cae98833802ae4b11c24ac7039a21d5af4b26c"
+dependencies = [
+ "serde",
+]
+
 [[package]]
 name = "heck"
 version = "0.5.0"
@@ -146,12 +155,70 @@ dependencies = [
  "proc-macro2",
 ]
 
+[[package]]
+name = "serde"
+version = "1.0.228"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9a8e94ea7f378bd32cbbd37198a4a91436180c5bb472411e48b5ec2e2124ae9e"
+dependencies = [
+ "serde_core",
+]
+
+[[package]]
+name = "serde_core"
+version = "1.0.228"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "41d385c7d4ca58e59fc732af25c3983b67ac852c1a25000afe1175de458b67ad"
+dependencies = [
+ "serde_derive",
+]
+
+[[package]]
+name = "serde_derive"
+version = "1.0.228"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d540f220d3187173da220f885ab66608367b6574e925011a9353e4badda91d79"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
 [[package]]
 name = "strsim"
 version = "0.11.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "7da8b5736845d9f2fcb837ea5d9e2628564b3b043a70948a3f0b778838c5fb4f"
 
+[[package]]
+name = "struct_iterable"
+version = "0.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "849a064c6470a650b72e41fa6c057879b68f804d113af92900f27574828e7712"
+dependencies = [
+ "struct_iterable_derive",
+ "struct_iterable_internal",
+]
+
+[[package]]
+name = "struct_iterable_derive"
+version = "0.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8bb939ce88a43ea4e9d012f2f6b4cc789deb2db9d47bad697952a85d6978662c"
+dependencies = [
+ "erased-serde",
+ "proc-macro2",
+ "quote",
+ "struct_iterable_internal",
+ "syn",
+]
+
+[[package]]
+name = "struct_iterable_internal"
+version = "0.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e9426b2a0c03e6cc2ea8dbc0168dbbf943f88755e409fb91bcb8f6a268305f4a"
+
 [[package]]
 name = "syn"
 version = "2.0.114"
@@ -170,6 +237,7 @@ dependencies = [
  "clap",
  "data-encoding",
  "progress_bar",
+ "struct_iterable",
 ]
 
 [[package]]
diff --git a/Cargo.toml b/Cargo.toml
index 17da2c9..3ded67f 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -7,3 +7,4 @@ edition = "2024"
 clap = { version = "4.5.54", features = ["derive"] }
 progress_bar = "1.4.0"
 data-encoding = "2.10.0"
+struct_iterable = "0.1.1"
diff --git a/src/assemble.rs b/src/assemble.rs
index 63527d2..c229a45 100644
--- a/src/assemble.rs
+++ b/src/assemble.rs
@@ -1,10 +1,21 @@
 use crate::exit;
 use progress_bar::*;
 use std::io::Write;
+use std::ops::Deref;
 use std::{fs::File, thread::sleep, time::Duration};
+use struct_iterable::Iterable;
 
 use crate::insturctions::get_hex;
 
+#[derive(Debug, Default, Iterable)]
+struct Instruction {
+  opt_code: u8,
+  arg1: u8,
+  arg2: u8,
+  arg3: u8,
+  arg4: u8,
+}
+
 pub fn assemble(code: Vec<String>, output: String) {
   let mut output_file = File::options()
     .create(true)
@@ -17,36 +28,55 @@ pub fn assemble(code: Vec<String>, output: String) {
 
   for line in code.iter() {
     let line_split: Vec<&str> = line.split(' ').collect();
-    let instruction = line_split[0];
-    let instruction_hex = get_hex(&instruction);
+    let mut line_iter = line_split.iter();
+    let opt_code = line_split[0];
+    let opt_code_hex = get_hex(&opt_code);
 
-    if !(instruction_hex.1 == (line_split.len() as i32 - 1)) {
+    if !(opt_code_hex.1 == (line_split.len() as i32 - 1)) {
       set_progress_bar_action("Error", Color::Red, Style::Normal);
       finalize_progress_bar();
       eprintln!(
         "Found {} arguments for {}, but expected {}",
         line_split.len() as i32 - 1,
-        instruction,
-        instruction_hex.1
+        opt_code,
+        opt_code_hex.1
       );
       exit(1)
     }
 
-    append_hex(
-      &mut output_file,
-      u8::from_str_radix(
-        instruction_hex.0.to_string().strip_prefix("0x").unwrap(),
-        16,
-      )
-      .unwrap(),
-    );
+    // append_hex(
+    //   &mut output_file,
+    //   u8::from_str_radix(opt_code_hex.0.to_string().strip_prefix("0x").unwrap(), 16).unwrap(),
+    // );
+
+    let mut instruction = Instruction::default();
+    instruction.opt_code =
+      u8::from_str_radix(opt_code_hex.0.to_string().strip_prefix("0x").unwrap(), 16).unwrap();
+
+    let mut args: Vec<u8> = Vec::new();
 
     for arg in &line_split[1..] {
-      let reg = u8::from_str_radix(arg.strip_prefix("0x").unwrap_or(arg), 16).unwrap();
+      args.push(u8::from_str_radix(arg.strip_prefix("0x").unwrap_or(arg), 16).unwrap());
+    }
+    println!("{:?}", args);
 
-      append_hex(&mut output_file, reg);
+    if args.len() >= 1 {
+      instruction.arg1 = args[0];
+    }
+    if args.len() >= 2 {
+      instruction.arg2 = args[1];
+    }
+    if args.len() >= 3 {
+      instruction.arg3 = args[2];
+    }
+    if args.len() >= 4 {
+      instruction.arg4 = args[3];
     }
 
+    println!("{:?}", instruction);
+    println!("{}", line_split.len() - 1);
+
+    append_hex(&mut output_file, instruction);
     sleep(Duration::from_millis(1));
     inc_progress_bar();
   }
@@ -56,6 +86,10 @@ pub fn assemble(code: Vec<String>, output: String) {
   println!("Finshed assembling progamm, output found in: {}", output);
 }
 
-fn append_hex(file: &mut File, hex: u8) {
-  file.write_all(&[hex]).unwrap();
+fn append_hex(file: &mut File, instruction: Instruction) {
+  for (field, val) in instruction.iter() {
+    file
+      .write_all(&[*val.downcast_ref::<u8>().unwrap()])
+      .unwrap();
+  }
 }
diff --git a/test.s b/test.s
index 8d608f5..ca9bb5a 100644
--- a/test.s
+++ b/test.s
@@ -1,8 +1,8 @@
-NOP 0xA1
-HALT 0xA1
-HALI 0xA1
-LOAD 0xA2 0xA2
-STOA 0xA2 0xA2
+NOP 0x01
+HALT 0x01
+HALI 0x01
+LOAD 0x02 0x02
+STOA 0x02 0x02
 MOV 0x03 0x03 0x03
 PUSH 0x02 0x02
 POP 0x02 0x02