Grass Pass

Project intro

Grass Pass turns your real local park into a one-page, black-and-white treasure hunt for your kid's age. Pick a park and an age band (4-6, 6-10, 10-13, or 13+ for teens and adults) and in about 10-30 seconds you get a printable page: 8 finds drawn from what is really in that park — Park Finds from OpenStreetMap, Wild Finds from recent iNaturalist sightings, Lucky Finds (a maybe dog) when enough recent Google reviews mention one — plus a Find This Spot map riddle with an X on a real landmark, and a grown-up's stub with the answer key and safety notes. Open-weight Gemma 4 writes the clues, but code does the trusting: every clue must quote its source word for word, 71 risky species groups are removed by species id before and after the model, and out-of-season plants are dropped by a season check. Example passes open with no sign-in, and your first new pass each day is free. The author built Grass Pass in one week with Claude Code set up as a small team — an architect agent wrote the spec, builder agents worked in parallel, and five reviewer agents checked the whole app through 12 review loops from 5 to 9 October 2026 — and the app carries 2,706 unit tests run on recorded real API answers with no mock data. It is a DEV Hacktoberfest 2026 Week 1 entry, live since 8 October 2026. Honest limits from the author: new passes take up to about 90 seconds when map servers are busy, quiet parks make short passes (the pass says so instead of padding), and the repository's last push was 11 October 2026, matching its hackathon cadence.