Depop's data engineering team cut the largest Spark pipeline's cost by 52%, described in a deep-dive on Databricks. The post walks through the specific inefficiencies found and the fixes that halved spend without touching dependencies. A concrete playbook for anyone paying for oversized Spark workloads.
Comet, the plan-translating Spark accelerator built on DataFusion, reached 1.0 with semantic versioning, full Spark 4.x/ANSI mode support, and all four join operators going native. It validates correctness by running Spark's own 24,000+ test suite with Comet enabled, plus fuzzing and AI code audits.
Jon Skeet's attempt to model Bible text in a tidy translation/book/chapter/verse schema collides with verse ranges, missing verses, alternate numbering, repeated chapters, and out-of-order text. The walkthrough shows how naive domains smuggle in real complexity, and why you should model only the complexity you actually need.
Embrasure open-sourced agent skills that debug and optimize Spark jobs from runtime evidence pulled via the Spark History Server's read-only REST API. The bundled collector snaps bounded, redacted data so agents can root-cause failures, spills, and skew instead of guessing. Apache-2.0.