Congrats, Dan! Fully agreed that given how most projects land the entrepreneur (and/or the investors) in the red, the real achievement here is executing an idea and seeing it through the full lifecycle of a business, in this case, through to a sale. The learning experience will be invaluable when you exit your next company.
This was a great story to follow through Hacker News, and your candor, detail, and introspection are admirable and indicative of the success ahead.