Writer A checks epoch 1 against base A, the transaction is rebased onto base B, and the premise the check established is lost before the commit lands

I tried to put data quality inside the commit. One pub(crate) stopped it.

A falsification experiment with a written kill list and a negative result. Delta has a purpose-built idempotent commit; iceberg-rust rebases a transaction onto a base the caller never checked, so an external writer cannot make a commit conditional. The green concurrency test was a false pass — 0 of 40 rounds ever raced — and only a failpoint showed the duplicate.

September 4, 2026 · 16 min · 3319 words · Andrea Bozzo

Guardrails for Tabular ML: A Data Engineer's Take on Data Leakage, Poisoning, and Brittle Pipelines

Most ML pipeline failures are not exotic model bugs — they are data issues that nobody encoded as checks. This article walks through building guardrails using pandas, Apache DataFusion, data contracts, and the Arrow C Data Interface.

March 23, 2026 · 13 min · 2649 words · Andrea Bozzo