data-engineering-disciplinelisted
Install: claude install-skill grimaldost/craft-collection
# Data Engineering Discipline
The output of a data pipeline is a contract. Columns, dtypes, row
cardinality, null behavior, group cardinality, and semantics are all part
of that contract, whether anyone wrote it down or not. This skill defends
against **silent breakage** — output that compiles, runs, and looks
plausible, but no longer means what consumers think it means. Every
principle in this skill exists because one of those guarantees has
historically been broken in a way that cost real money or real trust.
This skill is scenario-agnostic. The same discipline applies to migrating
a pipeline, creating a new one, refactoring an existing one, evolving a
schema, backfilling history, designing incremental loads, and
investigating downstream regressions. The specifics change; the
non-negotiables do not.
## Scoped-change lane
A bounded change to one transform or seam — a single tz-cursor fix, one emitter
field, a localized incremental load — does not need the full-migration
apparatus. Pin the contract for *that* seam (its schema / dtypes / semantics and
the consumers of the changed field), run only the parity and real-data checks
that touch it, and leave the rest of the pipeline alone — a wide scope is what
invites the "improving while executing" failure mode. The four non-negotiables
below still hold for the seam; what shrinks is the blast radius you verify, not
the rigor. Follow the project's own conventions over greenfield defaults
(python-engineering's edit lane owns tha