The impact you get to make at Wish is very significant. You'll mostly like make major contributions to the app, with almost full ownership through out the development cycle. A/B experiments (if they go well) will sometimes tell you that your features increased annual revenue by millions of dollars. As relevancy engineer, you will do a mix of data science work, like analyzing user behaviours and revenue trends, and engineer work, like product recommendation and product categorization algorithms.
You won't get a designated mentor and will be expected to be very self directed, but it wasn't hard to get help from the full time engineers. People tend to come in late (at 10-11) and leave late (at around 7-8) so the work hour tends to be a big long.
You get snacks, free crepes, catered lunch and dinner, which were pretty nice.