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answer: direct
beat: dev-practices
source: 1 article · updated: September 1, 2026
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How do you migrate the last 3% of files that automation can't fully finish?

Treat the long tail differently from the bulk: stamp every file with a machine-readable status of what has and hasn't succeeded, build a tool to rerun just the failing step on just the affected files, then run a tight loop — sample a handful of similar failures, tune the approach, sweep it across the category, repeat for the next failure pattern. LLM output on the hardest files still served as a usable starting point for the small remainder of manual cleanup.

Answered in

How to Migrate Thousands of Legacy Test Files With LLMs, Not Rewrites

A step-based pipeline, retry loops instead of perfect prompts, and rich context injection turn a year-long manual migration into a six-week automated one.

Crashtech Editorial September 1, 2026 Development Best Practices

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