# Three environments serve three different validation goals

Canonical URL: <https://datadriven.io/problems/three-environments-serve-three-different-validation-goals-d-3045aabd>

Domain: Pipeline Design · Difficulty: medium

## Problem

Three environments serve three different validation goals. Dev catches typos and broken refs; CI catches schema regressions and unit-test failures; staging catches integration issues and scale problems that slim CI does not. The section's data-shape choice per environment: dev gets sample data committed to the repo (tens to thousands of rows); CI gets a slim-CI subset of recent prod (modified models plus descendants); staging gets a subset of prod (last 7 days) or masked full prod with PII columns hashed. Choose the env data shape by adding three environment storage nodes downstream of a masking pipeline whose name states the data shape and PII handling for each.

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