Sorry to be late to this party (just signed up today after taking a break from my first month (or so) on Node-RED).
Here are my thoughts on Node-RED and production after some extensive testing with ESP devices (ESP32, ESP8266, WIMOS D1 (ESP8266) on WIFI and along with an Arduino UNO on serial with macOS in a variety of MQTT tests.
The only problem I have seen so far which would be problematic in a critical production application is the fact that I have seen Node-RED freeze during a Javascript exception. This happened to me just this week when, for some reason, the serial port mangles (I assume it was mangled by the serial driver) a JSON string and when Node-RED did not like that JSON string, it froze and needed to be restarted at least two times. The error was in the log file since I was running NR "nohup node-red &" on Ubuntu in this instance, and have all the logging in nohup.out.
In production, I would expect Node-RED to trap this "NR does not like the JSON" error, log it, and move on, but NR freezes. The poorly designed serial driver for the macOS (a macOS issue, not NR) was more-than-likely the cause, but seems to me, as a NR rookie, what NR should have trapped it, logged, it, and continued down it's merry processing path, versus locking up.
Please do not take this comment as negative; as I am a huge Node-RED fan... YUUUGG FAN and this issue did not dampen my passion for NR in the least. In fact, I just stopped testing on the USB serial interface, as it was just a test (and most of us macOS Arduino users know how unreliable the serial drivers can be....) . I was testing three ESP devices on WIFI and one Arduino UNO on macOS serial at the same time for about a week, stress testing over MQTT.
Should I report this error in a bug report?
I don't believe I have deleted the log file so that exception which caused NR to freeze a few times should still be in the logs, if needed by the NR team. Otherwise, I don't want to trouble anyone with the "untrapped" exception.
Node-RED is really great. In fact, it is one of the most interesting application development frameworks I have come across in years. I'm "in love".....
Considering I have only seen the one issue after building and testing myriad Node-RED flows, I can only say "WOW, great job NR Team". This is especially true for a V1.x version!!
CONGRATS!