diff --git a/src/netmd/encryption.rs b/src/netmd/encryption.rs
index fb1b9ab..944870c 100644
--- a/src/netmd/encryption.rs
+++ b/src/netmd/encryption.rs
@@ -9,11 +9,10 @@ use super::interface::DataEncryptorInput;
 type DesEcbEnc = ecb::Decryptor<des::Des>;
 type DesCbcEnc = cbc::Encryptor<des::Des>;
 
-pub fn new_thread_encryptor(
-    _input: DataEncryptorInput,
+pub fn threaded_encryptor(
+    input: DataEncryptorInput,
 ) -> UnboundedReceiver<(Vec<u8>, Vec<u8>, Vec<u8>)> {
     let (tx, rx) = unbounded_channel::<(Vec<u8>, Vec<u8>, Vec<u8>)>();
-    let input = Box::from(_input);
 
     thread::spawn(move || {
         let mut iv = [0u8; 8];
@@ -76,3 +75,103 @@ pub fn new_thread_encryptor(
 
     rx
 }
+
+pub struct Encryptor {
+    input_data: Vec<u8>,
+    iv: [u8; 8],
+    random_key: [u8; 8],
+    encrypted_random_key: [u8; 8],
+    default_chunk_size: usize,
+    current_chunk_size: usize,
+    offset: usize,
+    packet_count: usize,
+    closed: bool,
+}
+
+impl Encryptor {
+    pub fn new(input: DataEncryptorInput) -> Self {
+        let iv = [0u8; 8];
+
+        // Create the random key
+        let mut random_key = [0u8; 8];
+        rand::thread_rng().fill_bytes(&mut random_key);
+
+        // Encrypt it with the kek
+        let mut encrypted_random_key = random_key;
+        if let Err(x) = DesEcbEnc::new(&input.kek.into())
+            .decrypt_padded_mut::<NoPadding>(&mut encrypted_random_key)
+        {
+            panic!("Cannot create main key {:?}", x)
+        };
+
+        let default_chunk_size = match input.chunk_size {
+            0 => 0x00100000,
+            e => e,
+        };
+
+        let packet_count = 0;
+        let current_chunk_size = 0;
+
+        let mut input_data = input.data.clone();
+        if (input_data.len() % input.frame_size) != 0 {
+            let padding_remaining = input.frame_size - (input_data.len() % input.frame_size);
+            input_data.extend(std::iter::repeat(0).take(padding_remaining));
+        }
+
+        let offset: usize = 0;
+
+        Self {
+            input_data,
+            iv,
+            random_key,
+            encrypted_random_key,
+            current_chunk_size,
+            offset,
+            default_chunk_size,
+            packet_count,
+            closed: false,
+        }
+    }
+
+    /// Get the next encrypted value
+    pub async fn next(&mut self) -> Option<(Vec<u8>, Vec<u8>, Vec<u8>)> {
+        if self.closed {
+            return None
+        }
+
+        if self.packet_count > 0 {
+            self.current_chunk_size = self.default_chunk_size;
+        } else {
+            self.current_chunk_size = self.default_chunk_size - 24;
+        }
+
+        self.current_chunk_size = std::cmp::min(self.current_chunk_size, self.input_data.len() - self.offset);
+
+        let this_data_chunk = &mut self.input_data[self.offset..self.offset + self.current_chunk_size];
+        DesCbcEnc::new(&self.random_key.into(), &self.iv.into())
+            .encrypt_padded_mut::<NoPadding>(this_data_chunk, self.current_chunk_size)
+            .unwrap();
+
+        let output = (
+            self.encrypted_random_key.to_vec(),
+            self.iv.to_vec(),
+            this_data_chunk.to_vec(),
+        );
+
+        self.iv.copy_from_slice(&this_data_chunk[this_data_chunk.len() - 8..]);
+
+        self.packet_count += 1;
+        self.offset += self.current_chunk_size;
+
+        Some(output)
+    }
+
+    /// Call close to return none from subsequent calls
+    pub fn close(&mut self) {
+        self.closed = true;
+    }
+}
+
+pub fn encryptor() {
+
+}
diff --git a/src/netmd/interface.rs b/src/netmd/interface.rs
index 6057276..7be62ec 100644
--- a/src/netmd/interface.rs
+++ b/src/netmd/interface.rs
@@ -15,9 +15,9 @@ use std::collections::HashMap;
 use std::error::Error;
 use std::time::Duration;
 use thiserror::Error;
-use tokio::sync::mpsc::UnboundedReceiver;
 
 use super::base::NetMD;
+use super::encryption::{threaded_encryptor, EncryptorState};
 use super::utils::{cross_sleep, to_sjis};
 
 /// An action to take on the player
@@ -1691,7 +1691,10 @@ impl NetMDInterface {
         frames: u32,
         pkt_size: u32,
         // key, iv, data
+        #[cfg(not(target_family = "wasm"))]
         mut packets: UnboundedReceiver<(Vec<u8>, Vec<u8>, Vec<u8>)>,
+        #[cfg(target_family = "wasm")]
+        mut packets: EncryptorState,
         hex_session_key: &[u8],
         progress_callback: F,
     ) -> Result<(u16, Vec<u8>, Vec<u8>), InterfaceError>
@@ -1863,10 +1866,6 @@ pub struct MDTrack {
     pub data: Vec<u8>,
     pub chunk_size: usize,
     pub full_width_title: Option<String>,
-
-    #[allow(clippy::type_complexity)]
-    pub encrypt_packets_iterator:
-        Box<dyn Fn(DataEncryptorInput) -> UnboundedReceiver<(Vec<u8>, Vec<u8>, Vec<u8>)>>,
 }
 
 pub struct DataEncryptorInput {
@@ -1921,8 +1920,19 @@ impl MDTrack {
         [0x14, 0xe3, 0x83, 0x4e, 0xe2, 0xd3, 0xcc, 0xa5]
     }
 
+    #[cfg(not(target_family = "wasm"))]
     pub fn get_encrypting_iterator(&mut self) -> UnboundedReceiver<(Vec<u8>, Vec<u8>, Vec<u8>)> {
-        (self.encrypt_packets_iterator)(DataEncryptorInput {
+        threaded_encryptor(DataEncryptorInput {
+            kek: self.get_kek(),
+            frame_size: self.frame_size(),
+            chunk_size: self.chunk_size(),
+            data: std::mem::take(&mut self.data),
+        })
+    }
+
+    #[cfg(target_family = "wasm")]
+    pub fn get_encrypting_iterator(&mut self) -> EncryptorState {
+        EncryptorState::new(DataEncryptorInput {
             kek: self.get_kek(),
             frame_size: self.frame_size(),
             chunk_size: self.chunk_size(),