DTCS — Data Transformation Contract Standard

DTCS is a draft standard and toolkit for writing vendor-neutral data transformation contracts in YAML/JSON — the semantics of transforms, not a Spark, Polars, or SQL engine.

Status: Spec 3.0.0 (draft) · Tools 0.13.0 (alpha). Good for validation, compatibility analysis, portable relational profiles, and conformance research — not a production ETL runtime.

Documentation · Getting started · What DTCS is not · Adoption · Examples · Changelog · Security

Try it (no clone)

Requirements: Python 3.9+ for PyPI wheels, or Rust 1.75+ for cargo install (compile can take several minutes).

pip install dtcs
dtcs version
# → dtcs 0.13.0
# → spec 3.0.0

curl -fsSL https://raw.githubusercontent.com/eddiethedean/dtcs/main/examples/minimal.dtcs.yaml \
  -o contract.dtcs.yaml
dtcs validate contract.dtcs.yaml
# → valid
# → exit 0

Or paste the same file from examples/minimal.dtcs.yaml. Prefer dtcsVersion: "3.0.0"; prior versions remain accepted for compatibility.

Bindings: Python (pip install dtcs), WASM (@eddiethedean/dtcs-wasm), Node (@eddiethedean/dtcs). See docs/api/.

What this repository contains

• SPEC.md — normative DTCS 3.0 draft (27 chapters + Appendix A, including Rich Portable Analytics)
• Reference tools — parse, validate, analyze, plan, optimize, match, compile, and run contracts (Rust CLI + Python; limited WASM/Node surface)

Coverage tables labeled “Covered” or “Complete” mean the reference implementation exercises that draft SPEC area, not that DTCS 3.0 is finalized or production-certified.

Next steps (after valid)

Clone for richer examples and fixtures (PyPI wheels do not include examples/ or tests/):

git clone https://github.com/eddiethedean/dtcs.git
cd dtcs
dtcs validate examples/customer_pipeline.dtcs.yaml
dtcs run examples/customer_pipeline.dtcs.yaml \
  --input tests/fixtures/runtime/customer_pipeline_input.json

Develop from source

Requires Rust + maturin. See CONTRIBUTING.md.

Repository layout

Contributing

See CONTRIBUTING.md and CODE_OF_CONDUCT.md. Security reports: SECURITY.md. When guidance conflicts with the specification, SPEC.md wins.

License

Licensed under the Apache License, Version 2.0. See LICENSE.