I started a end-of-studies internship (Ms) at an early stage start-up doing R&D in ultrasound medical imaging. During my interview we agreed that I'll be paid for my work(without any written document since the startup isn't legally a thing yet). I live in a third world country where internships compensation is not guaranteed by the law and a very big number of interns do not get paid.

Months through my internship, I didn't receive any compensation, and when I brought the matter up, the managers said : "we agreed during the interview that the compensation will depend on the time spent and the performance" (which was not the case, they clearly said that it will be paid). I felt disrespected because my performance was quite good. I didn't talk about it though and focused on my actual work. But then I understood that another intern(same position as mine) was getting paid.

At the end of my internship I had a meeting with the managers where they expressed their satisfaction and asked me to stay with the team, but with a catch : they said they wanted to extend my internship for 2 more months( till end of August), because they are negotiating with investors and by that time, if everything went well, they will be able to offer me a full time position. We also talked about the compensation subject and why I was the only one not getting paid they gave me "unhonest" answers like they do not have funding, and also said that the other intern was a student of their CTO and that's why he was getting paid. They also said that they will pay me for the internship, but still no news till this day (a month ago).

Right now am not comfortable at work at all (besides the money, the culture and environment are really toxic, there is literally zero senior engineers in the team, only interns) lots of work and stress for free, but the work itself is challenging and enjoyable.

I have been applying to many jobs but with no answers and mainly rejections.

Now my question is : should I just leave my job and keep applying ( I mean am not getting paid after all) or should I stay as this will be a good boost to my resume (am a fresher btw). ( one more thing, there s no guarantee that by the end of august they'll have their money and be able to pay me).