# Barr Moses and the Monte Carlo team named the five pillars of data observability: freshness, distrib

Canonical URL: <https://datadriven.io/problems/barr-moses-and-the-monte-carlo-team-named-the-five-pillars-o-f4038ba2>

Domain: Pipeline Design · Difficulty: medium

## Problem

Barr Moses and the Monte Carlo team named the five pillars of data observability: freshness, distribution, volume, schema, and lineage. The pillars are not a checklist; they are a diagnostic framework. When a consumer reports a wrong number, a senior engineer walks the pillars in order and uses each to narrow or rule out a class of cause. Most quality programs cover four pillars well and lineage poorly because lineage at column granularity is expensive to keep current. Audit pillar coverage by adding five monitor nodes on the curated table, one per pillar, plus a catalog node that captures the lineage pillar (which upstream column produced which output column).

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