artifacts

File inputs and outputs form an executable pipeline. Run the pipeline button twice: the first run creates a source CSV, transforms it and copies the result; the second skips unchanged dependencies. Edit a row in artifact-demo/source.csv and run again to invalidate the transform. Delete either output to restore it.

deps= expresses execution cascade. inputs= instead discovers the producer through its outputs= and observes the file content. No explicit dependency is needed between transform and copy. A directly requested executable always runs.

The fixture is intentionally small; the same declaration can include parser code, patches and downloaded CSV/JSON/ZIP files in a data-processing project. External database revisions remain ordinary variables produced by an always observation block.