Your React or Next.js app got slower one release at a time. The bundle grew, images ship at full size, a third-party script blocks the first paint, a list re-renders on every keystroke. I measure which of those actually costs your users time, then fix the ones worth fixing.
I Will profile your React or Next.js app and make it faster, with numbers
Lighthouse and profiler on one page of your app, findings ranked by payoff.
- One page profiled, ranked
The audit, then the fixes that move the numbers, measured before and after.
- Audit plus the main fixes
- Source code
Up to 5 routes, rendering and caching, a bundle budget in CI, full comparison.
- Deep pass, up to 5 routes
- Source code
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Key details about this service to help you decide. Generated by Zinn Hub, not the seller.
Value Position
Measurement Approach
Frameworks Covered
Metrics Reported
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Full Description
Order this if you think slow pages are costing you signups or search traffic and you want to keep the app you have. React and Next.js already ship most of what a fast app needs, so the gains come from using those tools well rather than switching stacks.
You get numbers, not adjectives: LCP, CLS, INP and bundle size per route, measured before and after on the same throttled connection, in one table.
Starter is the audit of one page: the runs, the findings ranked by payoff, no code changed. Standard starts from that audit and spends the rest of the time on the fixes that move those numbers. Advanced covers up to 5 routes, tunes rendering and caching, and leaves a bundle budget in CI so the next release cannot quietly undo the work.
Work happens on a branch in your repository, commit by commit, each with its reason. Nothing is deployed by me unless you ask for it.
No calls. Everything in writing, including the measurements that disagree with me.
Steps for completing your project
1. Measure what your users actually get - Lighthouse on your live pages and a React profiler session on the slow ones, on a throttled connection. LCP, CLS, INP and bundle size per route, written down before anything is touched.
2. Find what costs the most - The bundle and the network waterfall: what ships that nobody uses, what blocks the first paint, which components re-render and why. Every finding carries an estimated saving in milliseconds or kilobytes.
3. Fix it, biggest win first - Code splitting, image and font handling, render-blocking work, memoization where the profiler asks for it, data fetching moved off the critical path. One commit per change, each with its reason.
4. Measure again, side by side - The same runs on the changed build: before and after in one table, per route and per metric. If a change made something worse, the table says so and the change goes back out.
5. Handover in your repository - A branch or patch in your repo, the report, and an honest list of what I did not do and what it would be worth. Deployment stays in your hands.
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Compare Packages
| Функция | Starter | Standard | Advanced |
|---|---|---|---|
| Delivery Time | 2 days | 4 days | 8 days |
| Revisions | 0 | 2 | 3 |
| Scope | One page profiled, ranked | Audit plus the main fixes | Deep pass, up to 5 routes |
| Source code | ✕ | ✓ | ✓ |
Portfolio
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Frequently Asked Questions
No, and be careful with anyone who promises it before seeing your code. A checkout widget or an ad script can cap the score whatever I do. The audit tells you your ceiling and what reaching it costs.
No. Vite, CRA, Remix or a plain SPA all profile the same way. Only the framework-specific fixes differ: route-level splitting and caching instead of Next.js rendering modes.
Yes. Standard begins with the same audit and spends the remaining time fixing what it found. Starter exists for teams who will do the work themselves and just need to know where to dig.
The audit sees that: server response time shows up separately from render and script cost. Profiling the API or the queries is the add-on, in Node, Express, NestJS or Rust.
Read access to the repository, or an archive of the source, plus the URL of the page. On Standard and Advanced I push the fixes to a branch, so I need permission to create one. If you'd rather not give it, I send a patch instead. I never need deploy access.
On your live production pages by default, so the numbers match what your users get. If the page is behind a login or not deployed yet, a staging link, a test account or steps to run it locally all work, and the report says which one the numbers come from.
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