I'd also recommend reading Aaron Ross's updated book

https://www.amazon.com/Impossible-Inevitable-Hyper-Growth-Co...

for software engineer's approaching marketing for the first time.

I made Menutail (https://www.menutail.com) which creates nutrition facts labels for food vendors. Up time is definitely important, but if things go wrong, customers are understanding if you communicate honestly with them on what is going on.

The other thing to be careful of is feature creep to ensure it is valuable for your customer base. If one customer complains that they want something which would be super difficult and applicable to only one edge case, I'd take some pause to evaluate the feedback.

The other thing as ovidiup mentioned, marketing is the absolutely hardest. I would even consider it soul draining if you like coding, but it is super necessary. I would recommend reading this book to help think about your sales channel

https://www.amazon.com/Impossible-Inevitable-Hyper-Growth-Co...