How AI is applied across API Evangelist and APIs.io. Read my AI disclosure →
API Evangelist API Evangelist
Discovery
Learnings
Guidance
Toolbox
Alignment
API Evangelist LLC
Discovery
Learnings
Guidance
Toolbox
Alignment
API Evangelist LLC

Need help?

Contact us

Project Haystack

Ontology / Vocabulary Built Environment openly published

Project Haystack is an open source initiative to streamline working with IoT Data...

Project Haystack, from their own meta description

Other built environment data models

ASHRAE 223P Semantic Data Model Ontology / Vocabulary BACnet object model Information Model Brick Schema Ontology / Vocabulary CityGML Information Model CityJSON Exchange Schema DALI (Digital Addressable Lighting Interface) Information Model gbXML (Green Building XML) Exchange Schema IndoorGML Information Model MUDDI (Model for Underground Data Definition and Integration) Information Model
← Back to all Data Models
Model Details
Steward Project Haystack
Layer Ontology / Vocabulary
Domain Built Environment
Status live
Access Openly published
Go to the steward →
How I know this

Compiled for the API Evangelist data model catalog, then confirmed against the steward's own site.

Confirmed 2026-08-11

Evidence: name evidence 2/2. Found something wrong? Tell me — corrections are cheap and I would rather be right.

Modernity Profile
72.7 Current
Access Open
Assessed 88.0% of the rubric

A separate measure from the Kin Score, which rates API providers. This rates how current a standard is in how it is expressed, published and paid for — not how good it is. EDIFACT and X12 score low here and move an enormous share of world trade.

Explore more
All Data Models API Standards Schemas Vocabularies