diff --git a/src/io.rs b/src/io.rs
new file mode 100644
index 0000000..3a406ff
--- /dev/null
+++ b/src/io.rs
@@ -0,0 +1,106 @@
+use wasm_bindgen::prelude::*;
+use serde::{Serialize, Deserialize};
+use crate::value::Value;
+use crate::vm::Panic;
+use imbl::Vector;
+use std::rc::Rc;
+
+
+#[wasm_bindgen(module = "/pkg/worker.js")]
+extern "C" {
+    async fn io (output: String) -> JsValue;
+}
+
+type Lines = Value; // expect a list of values
+type Commands = Value; // expect a list of values
+type Url = Value; // expect a string representing a URL
+type FinalValue = Result<Value, Panic>;
+
+fn make_json_payload(verb: &'static str, data: String) -> String {
+    format!("{{\"verb\":\"{verb}\",\"data\":{data}}}")
+}
+
+#[derive(Debug, Clone, PartialEq)]
+pub enum MsgOut {
+    Console(Lines), 
+    Commands(Commands), 
+    SlurpRequest(Url), 
+    Complete(Result<Value, Panic>),
+}
+
+impl std::fmt::Display for MsgOut {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        write!(f, "{}", self.to_json())
+    }
+}
+
+impl MsgOut {
+    pub fn to_json(&self) -> String {
+        match self {
+            MsgOut::Complete(value) => match value {
+                Ok(value) => make_json_payload("complete", value.to_json().unwrap()),
+                Err(_) => make_json_payload("complete", "\"null\"".to_string())
+            },
+            MsgOut::Commands(commands) => {
+                let commands = commands.as_list();
+                let vals_json = commands.iter().map(|v| v.to_json().unwrap()).collect::<Vec<_>>().join(",");
+                let vals_json = format!("[{vals_json}]");
+                make_json_payload("commands", vals_json)
+            }
+            MsgOut::SlurpRequest(value) => {
+                // TODO: do parsing here?
+                // Right now, defer to fetch
+                let url = value.to_json().unwrap();
+                make_json_payload("slurp", url)
+            }
+            MsgOut::Console(lines) => {
+                let lines = lines.as_list();
+                let json_lines = lines.iter().map(|line| line.stringify()).collect::<Vec<_>>().join("\n");
+                let json_lines = format!("\"{json_lines}\"");
+                make_json_payload("console", json_lines)
+            }
+        }
+    }
+}
+
+#[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
+#[serde(tag = "verb", content = "data")]
+pub enum MsgIn {
+    Input(String),
+    SlurpResponse(String, String, String),
+    Kill,
+    Keyboard(Vec<String>),
+}
+
+impl MsgIn {
+    pub fn to_value(self) -> Value {
+        match self {
+            MsgIn::Input(str) => Value::string(str),
+            MsgIn::SlurpResponse(url, status, string) => {
+                let url = Value::string(url);
+                let status = Value::keyword(status);
+                let string = Value::string(string);
+                let result_tuple = Value::tuple(vec![status, string]);
+                Value::tuple(vec![url, result_tuple])
+            }
+            MsgIn::Kill => Value::Nothing,
+            MsgIn::Keyboard(downkeys) => {
+                let mut vector = Vector::new();
+                for key in downkeys {
+                    vector.push_back(Value::String(Rc::new(key)));
+                }
+                Value::List(Box::new(vector))
+            }
+        }
+    }
+}
+
+pub async fn do_io (msgs: Vec<MsgOut>) -> Vec<MsgIn> {
+    let outbox = format!("[{}]", msgs.iter().map(|msg| msg.to_json()).collect::<Vec<_>>().join(","));
+    let inbox = io (outbox).await;
+    let inbox = inbox.as_string().expect("response should be a string");
+    let inbox: Vec<MsgIn> = serde_json::from_str(inbox.as_str()).expect("response from js should be valid");
+    inbox
+    
+}
+