+/* Wi-Fi credentials */
+extern const char config_wifi_ssid[];
+extern const char config_wifi_pass[];
+
+/* Network address of the server to contact */
+extern const char config_tattle_server_ip_address[];
+extern const u16_t config_tattle_port;
+
+/* For distinguishing reports from multiple tattlekey devices. */
+extern const u16_t config_this_tattler_identity;
+
+/* Which GPIO pin is the button connected to?
+ * The button should span this pin and ground, connecting this pin to ground
+ * when pressed.
+ * https://projects.raspberrypi.org/en/projects/introduction-to-the-pico/10
+ * recommends pins 18, 22, or 28. */
+extern const uint config_button_pin;
+
+/* Don't bother reporting each separate button press when it is pressed many
+ * times in short succession. (We also use this to de-bounce. :) */
+extern const u32_t config_minimum_seconds_between_button_presses;
+
+/* Send each report multiple times. Re-sends are sent with exponential delay:
+ * #1 sent immediately
+ * #2 after 1 seconds
+ * #3 after 2 seconds
+ * #4 after 4 seconds
+ * #5 after 8 seconds
+ * ...
+ * #11 after 8 minutes
+ * #12 after 17 minutes
+ * #13 after 34 minutes
+ * #14 after 68 minutes
+ * #15 after 2 hours
+ * #16 after 4 hours
+ * #17 after 9 hours
+ * etc.
+ * This provides some robustness against network outages, automatically
+ * replaying the log periodically to be collected after connectivity
+ * is restored. */
+extern const uint config_resend_count;