Here are my thoughts, in no particular order.<p>- Don&#x27;t work with a friend on a startup. You are very unlikely to be friends afterward. If you can&#x27;t easily compromise on something as unimportant as your stack, you&#x27;re going to disagree on way more important things. Why do you need two devs anyway?<p>- Two things that kills startups are analysis paralysis (always trying to make the perfect choice = wasting lots of time) and being afraid to leave your comfort zone. Both of you should be willing to use the other person&#x27;s stack because it will end this pointless argument and also help you learn something new (and possibly something you like even better than what you&#x27;re using now).<p>- If you&#x27;re using Angular, you have an objective reason to slightly prefer Node: it allows you to use a single language on the front and back ends.<p>- One possible compromise would be to use TypeScript, which was created by the same guy who created C#, so it shares lots of the same philosophy. TypeScript is also the native language of Angular now, so you can use it on the front and back ends.<p>- Another possible compromise would be for one of you to work on the back end only, and the other to work on the front end only.