US drinking water quality data by ZIP code — EPA violations, lead/copper levels, PFAS, radon, flood risk, and Home Safety Scores for 41,000+ ZIPs. 20 federal/state sources. Updated daily. CC BY 4.0.
A comprehensive package that includes the essential tools commonly used for different kind of codes in the US.
USPS v3 REST API client — OAuth 2.0, address validation, tracking, labels, rates. Drop-in replacement for usps-api (retired Jan 2026).
