diff --git a/fantemp/terminal.hpp b/fantemp/terminal.hpp
index ee44a67..8a1fa3a 100644
--- a/fantemp/terminal.hpp
+++ b/fantemp/terminal.hpp
@@ -10,6 +10,8 @@
 
 #include "controller.hpp"
 
+namespace detail {
+
 GF(ENDL, "\r\n");
 GF(HELP_CMD, "help");
 GF(SHOW_CMD, "show");
@@ -19,8 +21,7 @@ GF(BOOTLOADER_CMD, "bootloader");
 GF(VERSION_CMD, "version");
 GF(VERSION, "1.1");
 
-constexpr auto BACKSPACE = uint8_t{0x7f};
-constexpr auto CTRL_C = uint8_t{0x03};
+} // namespace detail
 
 template <class Uart>
 class Terminal {
@@ -29,9 +30,9 @@ class Terminal {
 	{
 		m_serial.init();
 
-		m_serial << ENDL;
+		m_serial << detail::ENDL;
 		printVersion();
-		m_serial << ENDL << F("$ ");
+		m_serial << detail::ENDL << F("$ ");
 	}
 
 	static void callback()
@@ -45,7 +46,7 @@ class Terminal {
 
 				// Handle Ctrl + C
 				if (inputByte == CTRL_C) {
-					m_serial << F("^C") << ENDL;
+					m_serial << F("^C") << detail::ENDL;
 					handleInput = true;
 					break;
 				}
@@ -66,13 +67,13 @@ class Terminal {
 				if (m_serial.peek(inputByte) && (inputByte == '\r' || inputByte == '\n')) {
 					m_serial.rxByte(inputByte);
 				}
-				m_serial << ENDL;
+				m_serial << detail::ENDL;
 				handleInput = true;
 				break;
 			}
 
 			if (m_inputSize >= INPUT_BUFFER_SIZE) {
-				m_serial << ENDL << F("WARNING: Terminal input buffer overflow!") << ENDL;
+				m_serial << detail::ENDL << F("WARNING: Terminal input buffer overflow!") << detail::ENDL;
 				handleInput = true;
 				break;
 			}
@@ -90,6 +91,8 @@ class Terminal {
 
   private:
 	static constexpr auto INPUT_BUFFER_SIZE = 128;
+	static constexpr auto BACKSPACE = uint8_t{0x7f};
+	static constexpr auto CTRL_C = uint8_t{0x03};
 
 	enum class State {
 		NONE,
@@ -106,17 +109,20 @@ class Terminal {
 		if (m_inputSize) {
 			if (m_inputBuffer[m_inputSize - 1] == CTRL_C) {
 				handleCtrlC();
-			} else if (strncmp_P(m_inputBuffer, reinterpret_cast<const char *>(HELP_CMD), m_inputSize) == 0) {
+			} else if (strncmp_P(m_inputBuffer, reinterpret_cast<const char *>(detail::HELP_CMD), m_inputSize) == 0) {
 				printHelp();
-			} else if (strncmp_P(m_inputBuffer, reinterpret_cast<const char *>(SHOW_CMD), m_inputSize) == 0) {
+			} else if (strncmp_P(m_inputBuffer, reinterpret_cast<const char *>(detail::SHOW_CMD), m_inputSize) == 0) {
 				showState();
-			} else if (strncmp_P(m_inputBuffer, reinterpret_cast<const char *>(CURVE_CMD), m_inputSize) == 0) {
+			} else if (strncmp_P(m_inputBuffer, reinterpret_cast<const char *>(detail::CURVE_CMD), m_inputSize) == 0) {
 				printCurve();
-			} else if (strncmp_P(m_inputBuffer, reinterpret_cast<const char *>(MONITOR_CMD), m_inputSize) == 0) {
+			} else if (strncmp_P(m_inputBuffer, reinterpret_cast<const char *>(detail::MONITOR_CMD), m_inputSize) ==
+			           0) {
 				m_state = State::MONITOR;
-			} else if (strncmp_P(m_inputBuffer, reinterpret_cast<const char *>(BOOTLOADER_CMD), m_inputSize) == 0) {
+			} else if (strncmp_P(m_inputBuffer, reinterpret_cast<const char *>(detail::BOOTLOADER_CMD), m_inputSize) ==
+			           0) {
 				handleBootloader();
-			} else if (strncmp_P(m_inputBuffer, reinterpret_cast<const char *>(VERSION_CMD), m_inputSize) == 0) {
+			} else if (strncmp_P(m_inputBuffer, reinterpret_cast<const char *>(detail::VERSION_CMD), m_inputSize) ==
+			           0) {
 				printVersion();
 			} else {
 				printUnknown();
@@ -126,19 +132,20 @@ class Terminal {
 
 	static void handleCtrlC()
 	{
-		m_serial << F("Abort!") << ENDL;
+		m_serial << F("Abort!") << detail::ENDL;
 		m_state = State::NONE;
 	}
 
 	static void printHelp()
 	{
-		m_serial << F("FanTemp command overview: ") << ENDL;
-		m_serial << HELP_CMD << F(" .......: print this help message") << ENDL;
-		m_serial << SHOW_CMD << F(" .......: shows current temperature and fan speed") << ENDL;
-		m_serial << CURVE_CMD << F(" ......: shows the curve used to map temperature to fan speed") << ENDL;
-		m_serial << MONITOR_CMD << F(" ....: loops the show command until Ctrl + C is pressed") << ENDL;
-		m_serial << BOOTLOADER_CMD << F(" .: enters the bootloader after 10 seconds") << ENDL;
-		m_serial << VERSION_CMD << F(" ....: displays firmware version") << ENDL;
+		m_serial << F("FanTemp command overview: ") << detail::ENDL;
+		m_serial << detail::HELP_CMD << F(" .......: print this help message") << detail::ENDL;
+		m_serial << detail::SHOW_CMD << F(" .......: shows current temperature and fan speed") << detail::ENDL;
+		m_serial << detail::CURVE_CMD << F(" ......: shows the curve used to map temperature to fan speed")
+		         << detail::ENDL;
+		m_serial << detail::MONITOR_CMD << F(" ....: loops the show command until Ctrl + C is pressed") << detail::ENDL;
+		m_serial << detail::BOOTLOADER_CMD << F(" .: enters the bootloader after 10 seconds") << detail::ENDL;
+		m_serial << detail::VERSION_CMD << F(" ....: displays firmware version") << detail::ENDL;
 	}
 
 	static void showState()
@@ -146,12 +153,12 @@ class Terminal {
 		char floatBuffer[16];
 
 		sprintf(floatBuffer, "%.2f", Controller::m_adcSample);
-		m_serial << F("ADC value ...: ") << floatBuffer << F(" / 1023") << ENDL;
+		m_serial << F("ADC value ...: ") << floatBuffer << F(" / 1023") << detail::ENDL;
 		sprintf(floatBuffer, "%.2f", Controller::m_resistance);
-		m_serial << F("Resistance ..: ") << floatBuffer << F(" Ohm") << ENDL;
+		m_serial << F("Resistance ..: ") << floatBuffer << F(" Ohm") << detail::ENDL;
 		sprintf(floatBuffer, "%.2f", Controller::m_temperature);
-		m_serial << F("Temperature .: ") << floatBuffer << F(" C") << ENDL;
-		m_serial << F("Fan speed ...: ") << Controller::m_fanSpeed << F("%") << ENDL;
+		m_serial << F("Temperature .: ") << floatBuffer << F(" C") << detail::ENDL;
+		m_serial << F("Fan speed ...: ") << Controller::m_fanSpeed << F("%") << detail::ENDL;
 	}
 
 	static void printCurve()
@@ -163,18 +170,18 @@ class Terminal {
 			for (uint8_t s = 0; s < Controller::mapTemperature(i); ++s) {
 				m_serial << "#";
 			}
-			m_serial << ENDL;
+			m_serial << detail::ENDL;
 		}
 	}
 
 	static void handleBootloader()
 	{
 		for (int8_t i = 10; i >= 0; --i) {
-			m_serial << i << ENDL;
+			m_serial << i << detail::ENDL;
 			_delay_ms(1000);
 		}
 
-		m_serial << F("Entering bootloader...") << ENDL;
+		m_serial << F("Entering bootloader...") << detail::ENDL;
 		m_serial.flushTx();
 
 		_delay_ms(1000);
@@ -184,7 +191,7 @@ class Terminal {
 
 	static void printVersion()
 	{
-		m_serial << F("FanTemp v") << VERSION << ENDL;
+		m_serial << F("FanTemp v") << detail::VERSION << detail::ENDL;
 	}
 
 	static void printUnknown()
@@ -192,7 +199,7 @@ class Terminal {
 		m_serial << F("Unknown command \"");
 		for (uint16_t i = 0; i < m_inputSize; ++i)
 			m_serial << static_cast<char>(m_inputBuffer[i]);
-		m_serial << F("\"") << ENDL;
+		m_serial << F("\"") << detail::ENDL;
 	}
 };