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How to migrate package.json eslintConfig to flat config

Convert static package.json eslintConfig blocks into flat config without evaluating JS.

Start here

The safe first move

When the repo exposes one static eslintConfig source in package.json, the bridge file can be generated cleanly.

Stop before automation when: Multiple ESLint config sources in one repo. Existing flat config files.

Target shape

module.exports = [
  ...compat.config({
    extends: ["eslint:recommended"],
    env: { node: true },
  }),
];

Repo fit check

Want to know if your repo has this pattern?

Run the matching scanner locally first. The fit-report add-on is not listed for this proof-only product yet, so use the proof page and scanner output before treating it as a purchase candidate.

  • Local scan; no repository upload.
  • Supported findings are separated from manual-review findings.
  • Buy only when the repeated pattern is worth automating.
Run the static-config scan View example report See when to buy 
Example scan summary
supported_findings: 38
manual_review_findings: 6
files_uploaded: 0
confidence: reviewable

Why this page exists

How to migrate package.json eslintConfig to flat config

package.json eslintConfig is a good automation target because the source is structured data.

Direct answer

What changes

When the repo exposes one static eslintConfig source in package.json, the bridge file can be generated cleanly.

Example

Before and after

Before

"eslintConfig": {
  "extends": ["eslint:recommended"],
  "env": {"node": true}
}

After

module.exports = [
  ...compat.config({
    extends: ["eslint:recommended"],
    env: { node: true },
  }),
];

Decision path

If this repeats across the repo, open the evaluation pages next.

This product exists for the static-config subset. It does not pretend to evaluate JS config logic.

  • Teams migrating static .eslintrc JSON or YAML configs.
  • Repos that still store eslintConfig inside package.json.
  • The fit-report add-on is not listed for this proof-only product yet; use the proof page and scanner output before treating this as purchasable.

Before checkout

Product fit, proof, and price should all be one click away.

Current listed price is not published on the pricing page yet.

Typical symptoms

  • The repo never had a standalone .eslintrc file.
  • Teams need a deterministic config export before plugin cleanup.
  • Reviewers want to know whether multiple config sources block the easy path.

What the product covers

  • Static package.json eslintConfig discovery and reporting.
  • Generated FlatCompat bridge in the supported subset.
  • Manual-review findings for multiple config sources.

Manual-review boundary

  • Multiple ESLint config sources in one repo.
  • Existing flat config files.
  • JS-driven config logic outside static data.

Keep the migration narrow

Use the exact-problem guides as a triage layer, then decide whether the repo is inside the supported subset.

FAQ

Fast answers before you decide

What is the safest fix for package.json eslintConfig flat config?

When the repo exposes one static eslintConfig source in package.json, the bridge file can be generated cleanly.

Can package.json eslintConfig flat config be automated?

Automate only the supported subset: Static package.json eslintConfig discovery and reporting. Generated FlatCompat bridge in the supported subset. Manual-review findings for multiple config sources. Keep these cases in manual review: Multiple ESLint config sources in one repo. Existing flat config files. JS-driven config logic outside static data.

When should I buy ESLint Flat Config Migration Cleanup Pack?

Use ESLint Flat Config Migration Cleanup Pack only when this pattern repeats across enough files that manual cleanup is still costly. Run the public scan or read the proof first. The fit-report add-on is not listed for this proof-only product yet; if unsupported findings dominate, keep the work manual.