Agreeing what data will be.
WHAT A DATA CONTRACT IS
An explicit agreement between a producer and consumers about structure, meaning, quality and change.
WHAT IT SPECIFIES
The schema Field meanings and units
Guarantees: freshness, completeness, uniqueness
How changes are communicated Who is responsible
WHY IT MATTERS
Most data incidents originate upstream, in changes nobody communicated.
WHAT IT CHANGES ORGANISATIONALLY
Data becomes a product with an owner, rather than a by-product taken without agreement.
WHAT ENFORCEMENT LOOKS LIKE
Automated schema checks before publication Tests failing the producer's build, not only the consumer's pipeline
WHY THAT DIRECTION MATTERS
Consumers otherwise absorb the cost of upstream changes indefinitely.
WHAT TO START WITH
The sources causing most incidents.
WHAT TO AVOID
Contracts so heavy nobody adopts them.
WHAT TO ESTABLISH MINIMALLY
Who to notify before a change What the schema is What the guarantees are
WHAT TO DOCUMENT WHERE CONTRACTS DO NOT EXIST
Your observed expectations, and test against them.
WHY
It converts a silent break into a detected one.
