Archive - The Data Letter

When Your Tests Pass But Your Data Fails

Testing code isn't enough. Test your data too.

Dec 4 •

November 2025

Year in Review: Top 3 Data Failures of 2025

Beyond the Obvious

Nov 30 •

Data Contracts in 5 Minutes

Stop upstream changes from breaking your models

Nov 23 •

How Netflix Does Data Reliability

The platforms and practices behind Netflix's reliable ML systems

Nov 16 •

dbt vs. Dataform: Which Should You Choose in 2026?

Three months ago, I sat in a conference room watching a data team explain why their feature engineering pipeline was broken.

Nov 9 •

Who Owns Data Quality, Anyway?

Data quality failures in production systems follow a predictable pattern.

Nov 2 •

October 2025

🎃 Night of the Living Dead DAGs

SpooOOOoooOOooky

Oct 29 •

Data Privacy Laws in 5 Minutes

Data privacy regulations exist because organizations consistently fail to track where sensitive information lives.

Oct 26 •

Finding Your $100,000 Query

Find and fix the queries draining your data budget.

Oct 22 •

Tool Review: Soda Core vs. Great Expectations

Declarative simplicity or programmatic power? How to pick your data quality foundation.

Oct 20 •

Building a Resilient Data Factory

Data Pipeline Design Patterns That Scale

Oct 15 •

Your First Breeze

A Beginner’s Guide to Airflow DAGs

Oct 12 •

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