How to Refactor Your Codebase with Eigent

How it works

1. Ask Eigent to map the area before editing — noisy modules, duplicated logic, unused code, and stale patterns.
2. Pick one cleanup theme at a time — remove unused code, simplify control flow, modernize an outdated pattern, or split a large file.
3. Before Eigent patches files, have it state the current behavior, the structural improvement, and the smallest check that proves behavior stayed stable.
4. Review and run the smallest useful check after each pass instead of batching the whole cleanup into one diff.
5. Keep stack changes, dependency migrations, and architecture moves as separate tasks unless required to finish the cleanup.

More prompts to try

• Which files in this area have the most dead code or unused exports?
• Identify all places where the same logic is duplicated and propose a single consolidation point.
• What legacy patterns in this module conflict with the repo's current conventions?
• Split this oversized file into smaller, clearly-owned pieces without changing its public API.

How to use

Start by asking Eigent to map the messy area — it will identify the highest-value cleanup opportunities before touching any code. Work one theme at a time and review each diff before moving on. Use your test suite or CI as the validation check after each pass. If Eigent proposes a stack migration or dependency change, flag it as a separate task and keep the current refactor focused on structure only.

Expected output

A prioritized cleanup plan, a series of small focused diffs (one per pass), and a validation summary for each pass showing what was changed and what check confirms behavior is stable.

Limitations

• Works best when the area has an existing test suite or clear behavioral contracts to validate against.
• Large monorepos benefit from scoping to one service or module at a time.
• Architecture changes, runtime upgrades, and framework migrations should be separate tasks — mixing them with refactoring makes diffs unreviewable.