diff --git a/Cargo.lock b/Cargo.lock
index 90dca37..d9383ff 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1072,6 +1072,12 @@ dependencies = [
  "unicode-normalization",
 ]
 
+[[package]]
+name = "if_chain"
+version = "1.0.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "cb56e1aa765b4b4f3aadfab769793b7087bb03a4ea4920644a6d238e2df5b9ed"
+
 [[package]]
 name = "include_dir"
 version = "0.7.3"
@@ -2573,6 +2579,7 @@ dependencies = [
  "chrono",
  "clap 4.4.11",
  "env_logger 0.10.1",
+ "if_chain",
  "include_dir",
  "libmodbus-rs",
  "log 0.4.20",
diff --git a/Cargo.toml b/Cargo.toml
index c5cb765..5655ca1 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -31,3 +31,4 @@ env_logger = "0.10"
 log = "0.4"
 serialport = "4.3"
 libmodbus-rs = "0.8.3"
+if_chain = "1.0.2"
diff --git a/control-loop.txt b/control-loop.txt
new file mode 100644
index 0000000..b456349
--- /dev/null
+++ b/control-loop.txt
@@ -0,0 +1,2 @@
+targeting pl's target voltage
+if load current > 0 or duty cycle < ~0.8 then there is power to spare
\ No newline at end of file
diff --git a/src/main.rs b/src/main.rs
index 04ab8af..bb7f695 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -39,7 +39,6 @@ enum Commands {
 
 #[tokio::main]
 async fn main() {
-    let args = Args::parse();
     env_logger::builder()
         .format_module_path(false)
         .format_timestamp(
@@ -51,10 +50,9 @@ async fn main() {
         )
         .init();
 
+    let args = Args::parse();
     let auth_path = args.config_dir.join("auth");
-
     let _ = CONFIG_PATH.set(args.config_dir.join("config.json"));
-
     let _recorder = metrics_prometheus::install();
 
     match args.command {
@@ -110,6 +108,8 @@ async fn main() {
                     }
                 };
 
+                // spawn a loop for each additional charge controller to log
+                // failed connections will print an error but the program will continue
                 let _additional_controllers: Vec<_> = access_config()
                     .additional_charge_controllers
                     .clone()
@@ -165,7 +165,7 @@ async fn main() {
                     tcrc_requests,
                 });
 
-                // spawn the api loop
+                // spawn the api / charge rate control loop
                 tokio::task::spawn(async move {
                     let mut normal_data_update_interval =
                         tokio::time::interval(std::time::Duration::from_secs(
@@ -208,6 +208,7 @@ async fn main() {
                                         .charge_state
                                         .is_some_and(|v| v.charging_state == ChargingState::Disconnected)
                                 {
+                                    // reenable control when charger is disconnected
                                     was_connected = false;
                                     tesla_charge_rate_controller.process_request(
                                         tesla_charge_rate::TcrcRequest::EnableAutomaticControl,
diff --git a/src/server/static_handler.rs b/src/server/static_handler.rs
index 3315fde..f2ea290 100644
--- a/src/server/static_handler.rs
+++ b/src/server/static_handler.rs
@@ -1,3 +1,4 @@
+use if_chain::if_chain;
 use include_dir::{include_dir, Dir};
 use rocket::{
     http::{ContentType, Status},
@@ -64,8 +65,10 @@ struct RawHtml {
 impl<'r> Responder<'r, 'static> for RawHtml {
     fn respond_to(self, request: &'r Request<'_>) -> rocket::response::Result<'static> {
         let mut response = self.data.respond_to(request)?;
-        if let Some(ext) = self.name.extension() {
-            if let Some(ct) = ContentType::from_extension(&ext.to_string_lossy()) {
+        if_chain! {
+            if let Some(ext) = self.name.extension();
+            if let Some(ct) = ContentType::from_extension(&ext.to_string_lossy());
+            then {
                 response.set_header(ct);
             }
         }
diff --git a/src/tesla_charge_rate.rs b/src/tesla_charge_rate.rs
index 382f4ab..62d1da9 100644
--- a/src/tesla_charge_rate.rs
+++ b/src/tesla_charge_rate.rs
@@ -1,5 +1,6 @@
 use std::sync::{Arc, RwLock};
 
+use if_chain::if_chain;
 use metrics::{describe_gauge, gauge, Gauge};
 use serde::{Deserialize, Serialize};
 
@@ -49,25 +50,21 @@ impl TeslaChargeRateController {
     }
 
     pub fn control_charge_rate(&mut self) -> Option<InterfaceRequest> {
-        if let Some(pl_state) = self.pl_state.as_ref().and_then(|v| v.read().ok()) {
-            if let Ok(car_state) = self.car_state.read() {
-                if let Some(charge_state) = car_state.charge_state {
-                    // we don't need to check if we're at home because we only call this when we are
-                    // TODO: enforce this through type system
-
-                    // automatic control or not, check if we're below shutoff voltage
-                    if pl_state.battery_voltage < access_config().shutoff_voltage {
-                        self.voltage_low += 1;
-                        if (self.voltage_low * access_config().charge_rate_update_interval_seconds)
-                            >= access_config().shutoff_voltage_time_seconds
-                        {
-                            return Some(InterfaceRequest::StopCharge);
-                        }
-                    } else {
-                        self.voltage_low = 0;
-                        if self.tcrc_state.read().is_ok_and(|v| v.control_enable) {
-                            return get_control(&pl_state, &charge_state);
-                        }
+        if_chain! {
+            if let Some(pl_state) = self.pl_state.as_ref().and_then(|v| v.read().ok());
+            if let Some(charge_state) = self.car_state.read().ok().and_then(|v| v.charge_state);
+            then {
+                if pl_state.battery_voltage < access_config().shutoff_voltage {
+                    self.voltage_low += 1;
+                    if (self.voltage_low * access_config().charge_rate_update_interval_seconds)
+                        >= access_config().shutoff_voltage_time_seconds
+                    {
+                        return Some(InterfaceRequest::StopCharge);
+                    }
+                } else {
+                    self.voltage_low = 0;
+                    if self.tcrc_state.read().is_ok_and(|v| v.control_enable) {
+                        return get_control(&pl_state, &charge_state);
                     }
                 }
             }
@@ -105,6 +102,8 @@ fn get_control(pl_state: &PlState, charge_state: &ChargeState) -> Option<Interfa
         return valid_rate(rate, charge_state.charge_amps).map(InterfaceRequest::SetChargeRate);
     }
 
+    // if max/min charge rate has changed, then the current charge rate might no longer be valid
+    // and we should move up/down to keep it in the new bounds
     valid_rate(charge_state.charge_amps, charge_state.charge_amps)
         .map(InterfaceRequest::SetChargeRate)
 }
diff --git a/src/types.rs b/src/types.rs
index c4fc70c..8c5d996 100644
--- a/src/types.rs
+++ b/src/types.rs
@@ -84,13 +84,6 @@ pub struct ChargeState {
     pub charge_limit_soc: i64,
 }
 
-impl ChargeState {
-    #[allow(unused)]
-    pub fn range_km(&self) -> f64 {
-        self.battery_range * 1.60934
-    }
-}
-
 impl From<teslatte::vehicles::ChargeState> for ChargeState {
     fn from(value: teslatte::vehicles::ChargeState) -> Self {
         ChargeState {
@@ -157,6 +150,7 @@ pub struct Coords {
     pub longitude: f64,
 }
 
+// ~111 metres
 const COORD_PRECISION: f64 = 0.001;
 
 impl Coords {