File Formats

YAML

YAML Ain't Markup Language

Adopt Community yaml.org / community spec Since 2001 Niche

Judgement: Adopt

Default surface for config and contract specs.

Human-readable data serialisation format. The default surface for metadata, configuration, and contract specifications — Kubernetes manifests, CI/CD pipelines, OpenAPI / AsyncAPI / ODCS / DPDS / dbt project files all live in YAML.

Why this is listed as niche

Strictly speaking a metadata and configuration format — rarely used to encode the data itself; its role is describing data, not carrying it. Listed because most schema and contract specs in this landscape (OpenAPI, AsyncAPI, ODCS, DPDS, dbt project files) are authored in YAML.

Example

Indentation for structure, plus block scalars for text that would be unreadable escaped.

order_id: 1001
city: Bamberg
amount: 49.90
items:
  - sku: A-1
    quantity: 2
note: >
  A folded block scalar: newlines in here
  become spaces when parsed.

At a glance

Category
File Formats
Governance
yaml.org / community spec
Status
Stable; v1.2.2 (2021)
First released
2001

Links

Related standards

Other standards in File Formats.

See YAML in context

Open the interactive Data Landscape to compare YAML against every other open standard, or grab the raw JSON. Spotted something wrong? Open an issue.