Build a faith companion that lives in iMessage
Flint is a Christian companion people text for prayer, verses and daily check-ins, with no app to download.
Make printable produce-season posters for your farmers’ market
A hobbyist built Vertumnus, customizable posters of when each produce variety is in season, in a single 731-prompt Claude session.
- Difficulty
- IntermediateOur rating
- Time to build
- 22 days (sourced)From the source
- Monthly cost
- Not reported
- Revenue
- Not reportedWe only show revenue the source states
- Engagement
- 47 HN points18 comments · fetched Oct 15, 2026
What they did
He coded it with Claude Opus over 22 days and published the full transcript.
How it went
Live for San Francisco and New York.
Worth knowing
He notes data at variety level was hard to find.
Builder recipe
Our own starting point, written from the source. Adapt it to your setup.
Stack
- Claude
Steps
- Give the agent access only to the accounts it needs.
- Write a clear brief with hard constraints.
- Ask it to report back before anything irreversible.
- Review the outcome and refine the brief.
Starter prompt
Tags
Read the original
- Hacker News: news.ycombinator.com/item?id=49604581 ↗ (opens in new tab) Sep 8, 2026 · 47 points, 18 comments (fetched 2026-10-15)
- Web: vertumnus.fyi ↗ (opens in new tab) Sep 8, 2026
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