[didibus]

As others have said, it doesn't sound like you're getting much of value. At this point, you might even ask instead for a big fat one time paycheck, if that's possible.

But, since you asked specifically what you could possibly do with the left over code, I believe Shopify has a market of add-ons, so I would look to see if you can't salvage some of the code as a Shopify add-on and sell it there. Maybe your ex co-founder can even become your first customer of it.

https://apps.shopify.com/

[ehnto]

Yeah, spin up a bunch of modules for different ecommerce platforms that integrate with your platform. See if your ex-co-founder will be your first customer, if they still need the service the software provided. It might actually turn out to be a fruitful relationship to have such a close feedback loop for shaping the software into something customers want. Just be careful not to accidentally build them a custom plugin only useful to them specifically. Charge them accordingly if they ask for big features. A lot of customers to SaaS products are willing to help fund feature development as custom work in addition to the recurring payments..