diff --git a/src/anchor_pkg/anchor_pkg/connector.py b/src/anchor_pkg/anchor_pkg/connector.py
index 5adafbc..e03fcd1 100644
--- a/src/anchor_pkg/anchor_pkg/connector.py
+++ b/src/anchor_pkg/anchor_pkg/connector.py
@@ -1,5 +1,6 @@
 from abc import ABC, abstractmethod
 from time import monotonic
+from typing import TYPE_CHECKING
 from astra_msgs.msg import VicCAN
 from std_msgs.msg import String
 from rclpy.clock import Clock
@@ -101,7 +102,7 @@ class SerialConnector(Connector):
         mcu_name: str | None = None
 
         # Serial buffering
-        self._serial_buffer = ""
+        self._serial_buffer: bytes = b""
         self._last_read_time = monotonic()
 
         if serial_override:
@@ -212,35 +213,40 @@ class SerialConnector(Connector):
         Returns:
             str: A hopefully-complete string read from the MCU via the serial interface.
         """
+        if TYPE_CHECKING:
+            assert type(self.serial_interface) == serial.Serial
+
+        # Warn on buffer timeout, as the only scenarios that would trigger this are
+        # a microcontroller output that isn't newline-terminated (bad), or the MCU is
+        # hanging (also bad).
         if (
             self._serial_buffer
             and (monotonic() - self._last_read_time) > SERIAL_READ_TIMEOUT
         ):
-            # Warn on buffer timeout, as the only scenarios that would trigger this are
-            # a microcontroller output that isn't newline-terminated (bad), or the MCU
-            # hanging (also bad).
             self.logger.warn(
                 f"Serial buffer timeout, last received '{self._serial_buffer}'."
             )
             result = self._serial_buffer
-            self._serial_buffer = ""
+            self._serial_buffer = b""
             self._last_read_time = monotonic()
-            return result
+            return str(result, "utf8").strip()
 
         # No try-except here so caller catches it instead.
-        raw = str(self.serial_interface.readline(), "utf8")
+        raw = self.serial_interface.readline()
 
+        # Empty or whitespace-only string
         if not raw or not raw.strip():
             return None
 
-        if not (raw.endswith("\n") or raw.endswith("\r")):  # unfinished string
+        # Add to buffer or send finished buffer
+        if not (raw.endswith(b"\n") or raw.endswith(b"\r")):  # unfinished string
             self._serial_buffer += raw
             self._last_read_time = monotonic()
             return None
         else:
             result = self._serial_buffer + raw
-            self._serial_buffer = ""
-            return result.strip()
+            self._serial_buffer = b""
+            return str(result, "utf8").strip()
 
     def read(self) -> tuple[VicCAN | None, str | None]:
         try: