SchemaSentry

SchemaSentry is a web app (with optional CLI) that monitors data warehouse schemas and contracts across Snowflake, BigQuery, and Redshift, then alerts before changes break downstream models, dashboards, and reverse ETL. It continuously snapshots table/column metadata, permissions, and key constraints, compares diffs, and maps impact to dbt models and BI assets using lineage ingestion. Teams can define “data contracts” (required columns, types, nullability, allowed enums, freshness) and enforce them in CI/CD and scheduled checks. When a change is detected, SchemaSentry opens a pull request comment or Slack alert with the exact breaking diff, impacted owners, and a suggested migration plan. This is not a generic catalog: it’s a focused guardrail for fast-moving analytics teams that keep getting burned by accidental renames, type changes, and permission tweaks.