My Second Year as a Solo Developer
Two cents offered because this post really strikes a chord with me, and I also spent some time chasing down rabbit holes early in my software business:These products do not appear obviously commercializable and multiple years invested into them without materially improving the businesses does not decrease my confidence in that snap judgment. You could probably talk to business owners with problems, launch an (appropriately priced; hundreds to thousands of dollars per year) product against those problems, build contingent on getting 10  commits to buy, and be at +/- $100k in 12 to 18 months. Many people with less technical and writing ability have done this in e.g. the MicroConf community. If you want the best paint-by-numbers approach to it I've seen, c.f. https://www.youtube.com/watch?v=otbnC2zE2rw&t=2s(I'll note that What Got Done is probably a viable boutique SaaS business if you somehow figured out distribution for it, at price points between $50 and $200 per month. My confidence on this approaches total. HNers skeptical because it is technically trivial should probably reflect for a moment on how much time is spent on standups at a company with 20 or 200 engineers, what one hour of their time is worth, and how likely that company is to put an engineer on this project specifically.)If you run an API-based business in the future: Usage-based billing is a really tricky business model for a solo developer. Note that you can say "Usage-based billing but we have a minimum commitment", and probably should prior to doing speculative integration engineering work. Your minimum commitment should be north of $1,000 per month; practically nobody can integrate with your API for cheaper than a thousand dollars of engineering time, right.This also counsels aiming at problems amenable to solutions with APIs which are trivially worth $1,000++ a month to many businesses which can hire engineers. Parsing recipe ingredients seems like a very constrained problem space. Consider e.g. parsing W-2s or bank statements or similar; many more businesses naturally care about intake of those documents, getting accurate data from them, and introducing that data into a lucrative business process that they have.I would encourage you, to the maximum extent compatible with your sanity, to prioritize "Will this get me more customers?" over behind-the-scenes investments like CI/CD which are very appropriate to Google but will under no circumstance show up in next year's report as One Of The Most Important Things I Did This Year.For similar reasons, I would suggest devoting approximately zero cycles to cost control. You don't have a cost problem and no amount of cost control will bend the curve of your current businesses to sustainability. You have a revenue problem. Your desired state in the medium term will make it economically irrational for you to think for more than a minute about a $50 a month SaaS expense; marketing and sales gets you to that desired state, not cost control.