I've been building projects I find interesting with AI tools since the beginning of the year, and lately I've been focusing on increasingly complex software, partially just as a challenge to myself, and partially to determine at what point the AI tools start to fail in the area of software development. For a recent project, I picked an intentionally too-ambitious goal: can I recreate most of a complex business application (in this case, Excel) in a week, for less than $100? How far can I actually get on that?
After planning it out pretty thoroughly with Claude, and brainstorming some additional AI enhanced features (e.g. plain english explanations for complex formulas and error diagnostics), I started on the implementation using the most recent Opus model. The bulk of that work only took a few days, with a few additional days of testing and polishing. I'm pretty happy with the results (the name HolySheet occurred to me and seemed pretty apt, so I went with that)... you can check it out for yourself here: https://www.holysheet.dev
I was able to build out most of the spreadsheet basics you'd expect (file manipulation, formulas, rich cell formatting and styling) as well as pivot tables and charts, multiple sheets, etc. I don't want to just do a feature dump here in this post, but the app is pretty full featured.
