Core Principles

The ten

• Raw is sacred — never mutate bronze, only append.
• One layer = one job. Bronze stores, silver cleans, gold serves.
• Idempotent pipelines — running twice produces the same result.
• Every row knows its source and its load timestamp.
• Schemas are versioned. Breaking changes get a new table.
• Naming is a contract. Follow the convention exactly.
• Failures are loud. Silent skips are bugs.
• Every job logs to an audit table.
• Backfills are first-class — design for them on day one.
• Prefer SQL in the warehouse over Python in memory.