DRTML overview

DRTML is the YAML contract shipped with a step package (*.drtml plus optional fragments). It is the source of truth for execution, params, datasets, feed, storage, metrics, generated UI, dashboard views and orchestration metadata.

Load and compile

main *.drtml
  → resolve relative include files
  → merge fragments
  → StepManifest (Pydantic)
  → version and cross-section validation
  → compile_step_manifest
  → immutable runtime plans

The DRTML layer performs no dataset I/O. Runtime consumes compiled plans.

Versions

• v3: builtin pattern or explicit execution.entry.
• legacy: execution.mode and runner remain supported where documented.

New steps should use v3 and a thin adjacent hook only when an entry is needed.

Package layout

src/acme_pipeline_steps/normalize/
  normalize.drtml
  fragments/
    params.drtml
    ui.drtml
    metrics.drtml
  hooks.py
  processor.py

Package DRTML files as distribution data. Airflow/UI discover their root through deployment configuration; manifest_path_adjacent resolves a main manifest from a thin hook.

What to read next

• Manifest reference
• Datasets and storage
• Feed reference
• Metrics and dashboards
• Streamlit form schema
• Execution and orchestration
• Extending DRTML

Boundaries

Steps do not parse DRTML. The parser does not perform parquet/database I/O. A YAML field without a compiled/runtime consumer is not a supported feature.