#Vercel (v0) → Replit

#Locate the app & detect package manager

• Check root package.json for a next dependency and for app/ or pages/ directories.
• If not at root, search common monorepo paths: apps/web, packages/frontend.
• Detect the package manager from the lockfile: package-lock.json→npm, pnpm-lock.yaml→pnpm, yarn.lock→yarn, bun.lockb→bun.

#Working directory

If Next.js lives in a subdirectory, every subsequent command runs from there. Update deploy_config_tool to cd into it:

• build: ["bash", "-c", "cd <dir> && <pkg-mgr> run build"]
• start: ["bash", "-c", "cd <dir> && <pkg-mgr> run start"]

#Ports & scripts

• dev: next dev -p 5000 -H 0.0.0.0
• start: next start -p 5000 -H 0.0.0.0

#Dev workflow

Vercel imports initialize with BEST_EFFORT_FALLBACK, which does not create a workflow for you. Configure one yourself with configure_workflow_tool before restart_workflow — the feedback and verification steps depend on it. Use the same subdirectory/pkg manager pattern as the build/start commands, e.g. ["bash", "-c", "cd <dir> && <pkg-mgr> run dev"].

#Replit compatibility rules

• instrumentation.ts/js: comment out if it blocks startup, leave a one-line explanatory comment.
• Build errors → source, not artifacts: when an error cites a file path, confirm whether it's source or compiled output before editing. Errors in compiled artifacts (Tailwind/CSS bundles, generated JS, type-gen output) point to a source cause — grep the source tree for the offending symbol or pattern and fix it there. Don't mask the error at the bundler/compiler layer (PostCSS rule-stripping, custom loader hacks, null-loader).
• External allowlists (preflight): grep source for image URLs passed to next/image and whitelist each external hostname under images.remotePatterns in next.config.mjs. Add '*.replit.dev' and '*.replit.app' to allowedDevOrigins. Skipping these produces runtime errors later.
• Binary asset spot-check: v0 and similar JSON-serialized project exports can ship images/fonts as base64 text files that pass HTTP 200 checks but fail to render. After clone, run file public/**/*.{png,jpg,webp,woff,woff2,ttf} (or wherever assets live) — any binary asset reported as ASCII/UTF-8 text needs base64 -d back to binary in place.
• Verify the running app, not just the build: a 200 response and a clean build log don't mean the page renders. Fetch the page (curl -s <URL> | head) and confirm the HTML contains real app content. Repetitive rebuild or reload loops in dev-server logs mean the app is cycling — don't blame the Replit proxy.

#Secrets

Always request env vars referenced by process.env.* (DATABASE_URL, API keys, etc.) through the environment-secrets skill so they land in the Replit Secrets store. Never ask the user to paste secret values into chat, don't commit them to the repo, and don't scrape .env into code.

#First message

One short, non-technical line. Don't enumerate steps or mention tools / library names. Template:

I've pulled in your Vercel project — looks like *a Next.js app for <feature>*. I'll get it running on Replit; this usually takes a few minutes. Nothing needed from you right now.

If you genuinely need a user-supplied secret later, batch it into one request via the environment-secrets skill.