{
  "id": 17244725,
  "title": "Shipping AI-assisted migrations without a big-bang PR",
  "url": "https://urgent.news/2026/10/30/shipping-ai-assisted-migrations-without-a-big-bang-pr",
  "topic": "ai",
  "section": "AI",
  "published": "2026-10-30T15:36:01.000Z",
  "source": {
    "name": "Dev.to",
    "slug": "dev-to",
    "url": "https://dev.to/sherotree/shipping-ai-assisted-migrations-without-a-big-bang-pr-39ap"
  },
  "original_language": "en",
  "account": "Migrating data-fetching layers to new clients using AI assistance can be challenging, but breaking the process into smaller, manageable pieces can help avoid big-bang PRs that are difficult to review, test, and rollback. AI is excellent at automating the mechanical aspects of a migration but struggles with determining the optimal size of the change to implement in a single go.\n\nOne effective approach is to focus on one surface area, such as a specific route group, feature module, or package boundary, rather than attempting to migrate everything at once. For instance, you could migrate only the settings routes, replacing legacyFetch with apiClient for those pages. It's crucial to define clear boundaries and stop rules to prevent the migration from expanding beyond its intended scope, especially when dealing with shared helpers.\n\nTo ensure that each PR is reviewable and maintainable, follow these guidelines:\n\n1. Scope the migration to a single surface area.\n2. Use a narrative diff with concise, human-written descriptions rather than AI-generated essays.\n3. Maintain contract-preserving tests that assert the same public behavior, even if the implementation details change.\n4. Write the migration behind a flag or export it as unused initially, then incrementally migrate one surface area at a time.\n5. Include fixtures or golden snapshots to capture the old behavior before rewriting. The new implementation should match these fixtures, and any deviation should cause the test to fail intentionally.\n6. Implement feature flags and dual-write windows for any side effects, allowing you to gradually enable the new client and monitor for mismatches before enabling it for the entire app.\n7. Write the rollback plan out loud before merging the migration slice, ensuring it's a simple and quick process. If the rollback would involve reverting multiple large commits, the migration slice was likely too extensive.\n\nBy adhering to these principles, you can leverage AI assistance to streamline the migration process while minimizing the risk of introducing bugs, hidden coupling, and difficult rollbacks. The key is to break the migration into small, manageable pieces and maintain control over the changes being made at each step.",
  "summary": "I asked an agent once to “migrate our data-fetching layer to the new client.” It came back with a 90-file PR, green CI, and a cheerful summary. I still couldn’t ship it. Reviewers bounced it. Rollback was a fantasy. Two weeks later we finished the same migration in six small PRs and nobody hated us. AI is great at the mechanical parts of a migration. It is terrible at deciding how much to change…",
  "key_points": [
    "Break migration into smaller, manageable pieces to avoid big-bang PRs.",
    "Focus on one surface area, like a route group or feature module.",
    "Use AI for mechanical aspects, human-written diffs for reviewability."
  ],
  "editors_take": null,
  "illustration": null,
  "coverage": {
    "outlets": 1,
    "also_reported_by": []
  },
  "ai_generated": true,
  "disclaimer": "Summaries, key points and the editor’s take are written by software from other outlets’ reporting and may contain errors — always check the linked original."
}