PinDrop
A community map for small acts of help around De Anza College and the Bay Area.
What it does
See what neighbors need or offer on a map, respond, message, and mark it done.
My contribution
Nearly all commits are mine; one comes from another contributor.
Challenges and decisions
Two people shouldn’t be able to claim the same request. Status changes go through a single database function that locks the pin row, and clients can’t update pins directly. That keeps the rule in one place at the cost of more database code.