How do you survive in a company which is venturing into development and you being the only developer

If you want to go home before you even started

Report insufficient staffing to your management in writing (email), making it their problem. Hiring enough people with relevant skilles is their job. Refuse to put in much overtime in case they don't do their job and don't hire enough people.

Update your resume and CV as "plan B".

I've left a company where I was the only developer in place, they were always demanding that I was so slow so to "motivate me" gave me a to do list for a month maybe more and ask me to finish in a week.

At that moment I was missing my last paycheck because of that, they were not gonna pay me untill that list was finished

One week later they gave me a memo because of not finishing that list, I went to my place, deleted personal stuff from my work computer and quit, it was like 3 or 4 years ago and still looking for a dev, thanks God I'm not there anymore

You become the shitty CTO/manager everyone bitches about here.