Multi Diff is a local-first workbench for comparing multiple unified diff files at once.

Visit multi-diff.vercel.app to use Multi Diff.

Instead of opening one patch at a time, you can load 2-5 diffs, assign them to lanes A-E, and review the same changed files across every candidate:

• Columns — side-by-side lanes for direct comparison
• Rows — full-width stacked reading when code needs more room
• Unified or Split — switch rendering style without changing the review
• Search — find changed content across every loaded diff

Everything runs in the browser. Diff content is not uploaded.

Most diff viewers are excellent at reviewing one patch. They become awkward when you need to compare several generated fixes, refactor attempts, or implementation variants.

Multi Diff is built for that comparison step. It keeps lane membership visible and lets you move between files intentionally.

• Multi-lane comparison — Review up to five diffs in lanes A-E.
• Column and row layouts — Compare side by side or read each diff at full width.
• Unified and split views — Use the renderer that fits the review.
• Staged imports — Drag files in, inspect the lane assignment, reorder, then apply.
• File tree navigation — Collapse directories, jump to files, focus the active path, and hide or restore files recursively.
• Content search — Search additions, deletions, and context with lane filters and highlighted matches.
• Sticky file headers — Keep the current file visible in each pane.
• Copy paths — Click file headers to copy paths with immediate feedback.
• Notes — Keep lightweight review notes next to the diff.
• Persistence — Layout, panes, notes, and display settings survive reloads.

Requires pnpm.

git clone https://github.com/bernaferrari/multi-diff
cd multi-diff
pnpm install
pnpm dev

Open http://localhost:3000.