I worked on a side project from Aug-Feb of 2020-2021, when I decided it could actually become a product that I'd like to release and, depending on reception, quit my job to grow into a business. Since Feb, I've productionized the codebase, set up infrastructure, created pitch decks, business plans, and feature specs for the upcoming beta. I've written about 100k lines of code, which are split between data processing pipelines and a front-end web app. The first addressable market is seasonal (Sep-Feb), which is why I haven't launched yet.I can't make the target closed beta release date alone and asked if my friend would help out. I told him we should come up with an equity split (even if it feels premature) that's favorable to both of us. It'll vest over 4 years with a 1 year cliff that kicks off when we get seed funding, when we both go full-time on it. He, being unfamiliar with startup investing and equity splits, told me to come to him with a split.I'm struggling to do that. If I were to do the whole thing on my own, I wouldn't be able to launch by my target date without cutting significant features but I do have the skillset to do it. He has no background in the business side of things.So, we're looking at a co-founder who:- Will be working part-time (same as me) until seed funding- Has a similar programming skillset (but more experience in production web app dev)- No business background- Coming into a project where the idea and release are mapped out, and 100k lines of code are written.- FAANG background (same as me)I want him to be motivated in case the beta goes well, but a 50/50 or 60/40 split seems unfair. To complicate it even more, the beta should be revenue-generating from day one, but of course who knows how well it'll perform. Could be a few hundred in revenue (10+ users), could be tens of thousands (200+ users).I'm considering an 85/15 split with a 50/50 revenue split after expenses. Am I totally wrong?