AI FOR DATA ENGINEERS

No hype. Just what works in production.

The long-form home of @dataeng.ai. Carousels and reels compress ideas; this is where they get the full breakdown, the code, and the evidence.

10 POSTS3 PILLARS
Featured / The account thesis
The three pillars
Latest
A dark server corridor where a single glowing email envelope drifts toward an exposed document vault, red alarm light overhead
2 AM PAGER

One email made Copilot leak private data, and the victim never clicked anything.

EchoLeak (CVE-2025-32711) slipped an attacker's email into Copilot's context past the injection filter, past link redaction, and out through an allowlisted Teams URL. The controls that failed all live in the retrieval layer.

2026-10-09READ
Two glowing gauge dials in a dark instrument panel, one needle swept high and one barely moved, connected by a pipeline
TOOL VERDICT

A reranker gained 14 points on Hit@10. The answers barely moved.

A MedCPT cross-encoder lifted Hit@10 by 14 points on 1,000 clinical QA pairs, and answer correctness moved under 4. The authors' own words: retrieval gains do not translate proportionally into answer gains.

2026-10-08READ
A dark industrial sorting machine splitting glowing token streams into two lanes, one lane feeding a loop that grows longer each cycle
TOOL VERDICT

Your router might be costing you more.

RouteLLM's paper promises 2x savings on single-turn benchmarks. We measured what happens in agent loops: switching models drops cache reads to zero, and the 1.25x write price gets paid again every turn.

2026-10-06READ
A dark vault corridor with glowing ledger books on steel shelves, one open page showing a hash key stamped in amber light
RESEARCH TO PRODUCTION

Rerunning an LLM step changes the output. Land it once, key it, and stop paying twice.

Temperature 0 was never deterministic. Treat every LLM call like a vendor API pull: land each response once, keyed on sha256 of input, model, and prompt version, and let backfills read the stored rows.

2026-09-29READ
A vast dark warehouse of glowing data cubes in perfect rows with a giant magnifying lens illuminating every single one
RESEARCH TO PRODUCTION

Your pipeline samples 2%. Judge all of them.

MotherDuck ran the numbers on judging all 100,000 rows: 89% accuracy, 40 seconds, fifty cents. The blocker was never accuracy. It was price.

2026-09-24READ
A massive steel one-way turnstile gate locked in a dark industrial corridor with a red warning beacon glowing above
2 AM PAGER

Airflow 3.3.2 shipped an upgrade trap, and the error message lies.

pandas 3 renames the DataFrame class path and XComs record the old one. Upgrade Airflow on every worker first, or the error message will send you chasing your config.

2026-09-23READ
A dark industrial control panel with a large glowing toggle switch flipped on and an analog meter needle pinned in the red zone
TOOL VERDICT

dbt turned its AI on by default. Check the toggle.

From September 1, Wizard and Copilot ship enabled and every future dbt AI feature auto-enables. The meter is running, and the pool is shared.

2026-09-22READ
A tiny pristine demo stage with one spotlight beside a vast dark industrial production floor with red warning lights
FAILURE MODES

Your demo worked. Your AI product won't.

Your demo ran on ten hand-picked examples. Production is the long tail of real inputs. Four things break, and none of them are the model.

2026-09-21READ
An on-call desk at 2 AM buried under an avalanche of printed support tickets, a glowing phone alert lighting the scene
2 AM PAGER

Your support bot is hallucinating. Blame the dumpster, not the model.

2:14 AM. The bot is inventing refund policies. The retriever is fine and the prompt is fine. The problem is the fourteen thousand tokens of dumpster you fed it.

2026-09-21READ