Agentic refactors & migrations
Mel for refactors & migrations
Scope a migration, apply it across the codebase, and verify it — without the find-and-replace anxiety. Mel makes the edits, runs your build and tests, and hands you a reviewable set of diffs to approve.
Why it helps
Big changes, under control.
Mel turns a sweeping refactor into a sequence of small, verified, approvable edits.
Scoped, not scattershot
Mel maps every call site before it touches a line, so a rename or API swap lands everywhere it should — and nowhere it shouldn't.
Verified as it goes
After each change Mel re-reads the file or runs your build and tests, so a migration doesn't silently break the tree.
Always reviewable
Every edit round-trips an approval card with a real line diff. Nothing lands that you didn't see.
How it works
Scope, change, verify — on repeat.
Mel works in small, safe increments and keeps going until the migration is actually done.
- 01
Scope the change
Describe the migration. Mel uses find and grep to enumerate every affected file and lays out a plan before editing.
- 02
Apply across the repo
Mel edits with exact, surgical replacements — read-before-edit, unique-match — creating files and rewriting call sites as needed.
- 03
Verify and review
It runs your build or tests after changes, fixes what breaks, and presents the whole set as diffs for you to approve.
Built in
Surgical edits with a safety net.
Mel makes large changes the careful way — exact edits, verified, and nothing applied behind your back.
Precise multi-file edits
edit_file and write_file apply exact changes with unique-match guards — the model can't smear a replacement across the wrong lines.
Approval on every change
Allow, always-allow per kind, or deny. Writes and commands never run behind your back.
Real diff cards
Each applied change shows a ± line diff in the transcript, plus accurate files-changed counts.
Parallel with worktrees
Spin up git worktrees per branch from the tab bar to run migrations in isolation.
Isolated by default
Run migrations in a worktree.
Spin up a git worktree from the tab bar — Mel generates a branch name and checks it out into its own directory — so a sweeping migration runs in isolation and never touches your working branch until you choose to merge.
- git worktree per branch, one click
- Auto-generated branch names
- Run parallel migrations side by side
- Your main branch stays clean
More use cases
What else Mel can do.
Code review
Review diffs with full-repo context, enforce conventions, and iterate on the fix in your terminal.
ExploreBug investigation
Reproduce vague bugs, capture the evidence, and trace the cause back to the line.
ExploreIncident response
Investigate alerts, inspect logs on the affected host, summarize, and prepare the fix.
ExploreMigrate without holding your breath.
Let Mel scope, apply, and verify the change set — and review the diffs before anything lands on your branch.