Trilemma Data

Browse the Full Catalog

IntermediateTiny

Official Spanish adverse-weather CAP warning Atom feed from AEMET for inspecting alert IDs, updates, and affected regions.

First Project: Inspect Spanish CAP Publications

EnvironmentAtom +1No Key

IntermediateLarge

Annual U.S. demographic, housing, social, and economic estimates for building local market-sizing, site-selection, and community comparison tools.

First Project: Screen States for a Service-Market Hypothesis

DemographicsJSON +1Key

BeginnerTiny

The Appalachian Regional Commission's maintained county membership list for building regional comparison and eligibility tools.

First Project: Compare ARC County Membership

DemographicsHTML +1No Key

BeginnerTiny

Slovenian river and lake station measurements for building a local water-level conditions display.

First Project: Inspect Dated Local Conditions

EnvironmentXMLNo Key

IntermediateSmall

Open preprint descriptive metadata for building topic alerts and research discovery tools that link back to arXiv.

First Project: Watch Recent Machine-Learning Preprints

ResearchAtom XMLNo Key

IntermediateTiny

Official Austrian civil-emergency alerts from the AT-Alert public API for reviewing affected polygons, alert levels, and validity intervals.

First Project: Inspect Austrian Civil Alerts

EnvironmentJSONNo Key

BeginnerTiny

European regional avalanche bulletins published as CAAML JSON for building a dated mountain hazard view.

First Project: Review Regional Avalanche Bulletins

EnvironmentJSONNo Key

BeginnerTiny

Current airport METAR observations and station metadata from NOAA's Aviation Weather Center for checking representative weather conditions near destinations.

First Project: Check One Airport Observation

EnvironmentJSON +1No Key

Compare Available Datasets
			Formats
AEMET Spain CAP Warnings	Environment	APINo Key	Atom +1	Intermediate	Near Real Time
American Community Survey 5-Year Estimates	Demographics	API+DLKey	JSON +1	Intermediate	Annual
ARC Appalachian Counties	Demographics	DownloadNo Key	HTML +1	Beginner	Annual
ARSO Current Hydrology	Environment	APINo Key	XML	Beginner	Near Real Time
arXiv Preprint Metadata	Research	APINo Key	Atom XML	Intermediate	Daily
Austria AT-Alert Public Warnings	Environment	APINo Key	JSON	Intermediate	Near Real Time
Avalanche.report Regional Bulletins	Environment	DownloadNo Key	JSON	Beginner	Daily
Aviation Weather Center METAR and Stations	Environment	APINo Key	JSON +1	Beginner	Continuous

Build an Alerting Tool

Official feeds that can power a focused monitor for hazards, health, or security without scraping or paid data.

9 Datasets

Open Path

Compare Places

Authoritative local and national statistics for sizing a market, choosing a site, or comparing communities.

10 Datasets

Open Path

Discover Research and Citations

Scholarly and trial metadata for topic alerts, literature monitors, and research discovery tools that link back to the source.

8 Datasets

Open Path

Plan for a Local Area

Weather, flood, housing, and infrastructure sources for a neighborhood-scale planning prototype.

10 Datasets

Open Path

Start with a First Microproduct

Beginner, no-key sources with a small first project you can finish in an afternoon without paid infrastructure.

11 Datasets

Open Path

Track Regulatory Change

Primary legal and screening sources for watching rules, filings, and sanctions lists as they change.

9 Datasets

Open Path

Choose a Dataset. Build a Microproduct.

252 Datasets

Browse the Full Catalog

Start from a Build Path

Build an Alerting Tool

Compare Places

Discover Research and Citations

Plan for a Local Area

Start with a First Microproduct

Track Regulatory Change

Filter Datasets