 #define DHTPIN 10
 #define DHTTYPE DHT22
 
-// init. DHT
-DHT dht(DHTPIN, DHTTYPE);
+//
+// For normal use, we require that you edit the sketch to replace FILLMEIN
+// with values assigned by the TTN console. However, for regression tests,
+// we want to be able to compile these scripts. The regression tests define
+// COMPILE_REGRESSION_TEST, and in that case we define FILLMEIN to a non-
+// working but innocuous value.
+//
+#ifdef COMPILE_REGRESSION_TEST
+#define FILLMEIN 0
+#else
+#warning "You must replace the values marked FILLMEIN with real values from the TTN control panel!"
+#define FILLMEIN (#dont edit this, edit the lines that use FILLMEIN)
+#endif
 
 // This EUI must be in little-endian format, so least-significant-byte
 // first. When copying an EUI from ttnctl output, this means to reverse
 // the bytes. For TTN issued EUIs the last bytes should be 0xD5, 0xB3,
 // 0x70.
-static const u1_t PROGMEM APPEUI[8]= { YOUR_APPEUI_HERE };
+static const u1_t PROGMEM APPEUI[8] = { FILLMEIN };
 void os_getArtEui (u1_t* buf) { memcpy_P(buf, APPEUI, 8);}
 
 // This should also be in little endian format, see above.
-static const u1_t PROGMEM DEVEUI[8] = { YOUR_DEVEUI_HERE };
+static const u1_t PROGMEM DEVEUI[8] = { FILLMEIN };
 void os_getDevEui (u1_t* buf) { memcpy_P(buf, DEVEUI, 8);}
 
 // This key should be in big endian format (or, since it is not really a
 // number but a block of memory, endianness does not really apply). In
 // practice, a key taken from the TTN console can be copied as-is.
-static const u1_t PROGMEM APPKEY[16] = { YOUR_APPKEY_HERE };
+static const u1_t PROGMEM APPKEY[16] = { FILLMEIN };
 void os_getDevKey (u1_t* buf) {  memcpy_P(buf, APPKEY, 16);}
 
 // payload to send to TTN gateway

    .rssi_cal = 8,              // LBT cal for the Adafruit Feather M0 LoRa, in dB
    .spi_freq = 8000000,
};

void onEvent (ev_t ev) {
    Serial.print(os_getTime());

// Schedule TX every this many seconds (might become longer due to duty
// cycle limitations).
const unsigned TX_INTERVAL = 30;

// Pin mapping for Adafruit Feather M0 LoRa
const lmic_pinmap lmic_pins = {
