teckel-rs

Rust implementation of the Teckel Specification v3.0 -- a declarative YAML-based language for defining data transformation pipelines.

This crate provides the parser and model layer: YAML parsing, variable/secret resolution, validation, and conversion to a typed domain model. The execution backend is implemented in a separate repository.

Crates

Crate	Description
teckel-model	Core domain types: assets, sources, 45 transformation types, error catalog, quality, metadata
teckel-parser	YAML deserialization, variable substitution, secret resolution, config merging, validation (V-001..V-008), rewrite to domain model

Quick Start

use teckel_parser::parse;
use std::collections::BTreeMap;

let yaml = r#"
version: "2.0"
input:
  - name: employees
    format: csv
    path: "data/employees.csv"
    options:
      header: true
transformation:
  - name: active
    where:
      from: employees
      filter: "status = 'active'"
output:
  - name: active
    format: parquet
    path: "output/active_employees"
    mode: overwrite
"#;

let context = parse(yaml, &BTreeMap::new()).unwrap();
// context is a BTreeMap<AssetRef, Asset> representing the pipeline DAG

Conformance

This parser supports parsing all constructs defined in the Teckel v3.0 specification:

• Core (Sections 1-12): Document structure, inputs, outputs, 10 basic transformations, expression language (as raw strings), data types, null semantics, variable substitution, path resolution, validation rules, execution model, error catalog
• Extended (Sections 8.11-8.31, 13-21): All 45 transformations, secrets, configuration, hooks, data quality, metadata, exposures, templates, config merging

Build

cargo build
cargo test
cargo clippy

License

Apache License 2.0