diff --git a/tester/cmd.json b/tester/cmd.json
new file mode 100644
index 0000000..8a99e7d
--- /dev/null
+++ b/tester/cmd.json
@@ -0,0 +1,7 @@
+{
+  "type": "Ota",
+  "content": {
+    "url": "http://192.168.1.10/sphinx-update-",
+    "version": 0
+  }
+}
diff --git a/tester/src/ctrl.rs b/tester/src/ctrl.rs
index e7f97f3..f1cc9f1 100644
--- a/tester/src/ctrl.rs
+++ b/tester/src/ctrl.rs
@@ -1,6 +1,6 @@
 use dotenv::dotenv;
 use serde::{Deserialize, Serialize};
-use sphinx_key_parser::control::{ControlMessage, Controller, OtaParams};
+use sphinx_key_parser::control::{ControlMessage, Controller};
 use sphinx_key_signer::lightning_signer::bitcoin::Network;
 use std::env;
 use std::time::Duration;
@@ -25,16 +25,16 @@ async fn main() -> anyhow::Result<()> {
     let seed = hex::decode(seed_string).expect("yo");
     let mut ctrl = controller_from_seed(&Network::Regtest, &seed, nonce);
 
-    let version_string: String = env::var("VERSION").unwrap_or("0".to_string());
-    let version: u64 = version_string.parse::<u64>().expect("failed to parse version");
-    let ota_url: String = env::var("OTA_URL").unwrap_or("http://192.168.1.10/sphinx-update-".to_string());
-    let control_message = ControlMessage::Ota(OtaParams {
-        version: version,
-        url: ota_url
-    });
+    let mut command = ControlMessage::Nonce;
+    if let Ok(cmd_content) = std::fs::read_to_string("./tester/cmd.json") {
+        if let Ok(cmd) = serde_json::from_str::<ControlMessage>(&cmd_content) {
+            command = cmd;
+        }
+    }
 
-    //let msg = ctrl.build_msg(control_message)?;
-    let msg = ctrl.build_msg(ControlMessage::Nonce)?;
+    println!("COMMAND! {:?}", command);
+
+    let msg = ctrl.build_msg(command)?;
     let msg_hex = hex::encode(&msg);
 
     let client = reqwest::Client::builder()