Benchmark React or Next.js changes on Vercel Sandbox VMs with paired A/B statistics: react PR/commit vs base, or Next.js PR/commit vs base, measured end-to-end through the bench/render-pipeline app (rps, latency, p95; TTFB, RSS and document/Flight bytes when the Next side captures them) and, for React changes, through the react repo's flight-ssr-bench fixture (Node AND Edge web-streams paths…
Install
npx skills add vercel/next.js --skill sandbox-benchnpx skills add vercel/next.js --skill sandbox-bench -a claude-code -gnpx skills add vercel/next.js --skill sandbox-bench -a codex -ggemini skills install https://github.com/vercel/next.js.git --path .agents/skills/sandbox-benchgh skill install vercel/next.js sandbox-benchgit clone --depth 1 https://github.com/vercel/next.js /tmp/vercel__next.js
mkdir -p ~/.claude/skills ~/.agents/skills
cp -R /tmp/vercel__next.js/.agents/skills/sandbox-bench ~/.claude/skills/sandbox-bench # Claude Code
cp -R /tmp/vercel__next.js/.agents/skills/sandbox-bench ~/.agents/skills/sandbox-bench # Codex, Cursor, Gemini CLI, Copilot, OpenCode