Some background first. I'm a student engineer in France, and I started a 6 months internship a month ago, in a start-up. I'm working as a developer. We're around 8 people working here, in a very good ambiance I must add. However, apart from my boss and the project manager, we're only interns.
The problem
We're only two interns, including me, to work as developers. In a week or so, we'll need to add a new feature to the application we're working on. Compared to the previous month which was only bug fixing and minor modifications, this is a huge step.
We're left with the previous intern code, and this code is too hard for me to work with. The other intern who studied during 4 years the technology we're using (I only studied it for 5 months) is feeling the same as me.
I don't know whether or not we will be able to accomplish the work we were tasked with. To be more precise, I believe we can, but I think our solution will be sub optimal, and the people who will work with our code next will be left with a really messy work.
In the end, I'm concerned about the quality of our work. I don't feel like bringing the "I'm only an intern" talk to my boss because as I said, the previous code was written by an intern.
There's also the fact that this is the start-up first product, and a huge investment for my boss who created it.
How should I talk to my boss about this?