Agency handoff is at risk
A client project is close to delivery, but the dashboard or critical flow still feels slow.
Senior React & Next.js engineer
Production
ready is a
performance
decision.
I help React/Next.js agencies and SaaS teams keep slow order-management, POS, dashboard, and customer flows responsive—with browser evidence and real-device checks.
SIMULATION DASHBOARDLIVE TRACE
FRAME RATE60FPS7,000+ visual entities · LCP under 2.5s
Evidence first. Scope protected.
Validated before and after.
The service
Not score cosmetics.
Production readiness.
A fast-shipped frontend can work in preview and still fail under real users, devices, busy order queues, and handoff pressure.
Orders or checkout fall behind
Order creation, status changes, inventory search, or checkout lags when staff are busy.
Mobile or tablet exposes the weakness
The build is fine on a development laptop but stutters on the devices people use at the counter.
The dashboard feels heavy
Filters, charts, tables, route changes, or typing lag when real data arrives.
Fast-shipped code is fragile
AI-assisted delivery created client-side bloat, duplicate logic, or weak loading states.
The team needs a fix order
There are warnings, but no evidence-backed root-cause map or acceptance criteria.
What buyers are really purchasingFaster order and checkout flows · Lower launch risk · Clearer engineering priorities · Before/after evidence
Not included: generic website speed work, a Lighthouse 100 guarantee, backend remediation, payment or inventory integrations, security auditing, or an open-ended application rewrite.
Fixed-price tiers
Choose the smallest tier
that answers the next decision.
Start with triage when the cause is unclear. Move to recovery only when implementation is the actual need.
01 / starter
Performance Triage Lite
Quick audit of one React/Next.js page with CWV, Loom, and fix plan.
$349fixed price
3 days2 revisions1 page
1 page
- Lighthouse and PageSpeed baseline
- Chrome DevTools quick profiling
- LCP, INP, and CLS diagnosis
- Mobile and tablet responsiveness check
You’ll complete payment securely through Upwork.
02 / standard
Prod Readiness Diagnostic
Deep React/Next.js audit: traces, risks, and a fix roadmap.
$949fixed price
5 days4 revisions5 pages
5 pages
- Performance trace review
- React and Next.js rendering-risk review
- Hydration and bundle review
- Main-thread blocking diagnosis
You’ll complete payment securely through Upwork.
03 / advanced
Performance Recovery Sprint
Fix top React/Next.js bottlenecks with before/after validation.
$2,199fixed price
10 days8 revisions7 pagessource code
7 pages
- Fix 3–5 high-impact frontend bottlenecks
- Rendering, hydration, image, font and script improvements
- Bundle reduction opportunities
- Mobile and tablet responsiveness improvements
You’ll complete payment securely through Upwork.
| Tier | Days | Coverage | Primary output | Implementation |
|---|---|---|---|---|
| Starter · $349 | 3 | 1 page | Fast diagnosis and fix plan | Very small safe fix only |
| Standard · $949 | 5 | 5 pages | Deep diagnosis and roadmap | Not included |
| Advanced · $2,199 | 10 | 7 pages | 3–5 fixes plus validation | Included within scope |
Diagnostic coverage
A score is not
the diagnosis.
Lighthouse and PageSpeed establish a baseline. Traces, code paths, and device behavior explain why the product feels slow.
See the rescue process →| Evidence | Tool / signal | Purpose |
|---|---|---|
| LAB | Lighthouse | Repeatable baseline |
| FIELD | CrUX / RUM | Production signal |
| TRACE | DevTools | Root-cause evidence |
| DEVICE | Real mobile | User-condition check |
Delivery model
Diagnosis, scope, implementation,
and validation are separate decisions.
01Define→
02Baseline→
03Profile→
04Root cause→
05Recover→
06Validate
Frequently asked questions
Clear boundaries
before work begins.
01Do you guarantee a Lighthouse 90+ score?
No. I do not sell cosmetic Lighthouse scores, and a Lighthouse 100 is never promised. I focus on Core Web Vitals, main-thread blocking, rendering cost, mobile responsiveness, bundle weight, and user-perceived performance, then validate before and after under comparable conditions.
02My app was built with AI tools (Cursor, v0, Copilot). Can you help?
Yes. I review and improve React/Next.js frontends built or accelerated with Lovable, Replit, v0, Cursor, Copilot, or similar tools when they need production hardening, such as client-side bloat, duplicate logic, or weak loading states.
03Which tier should I choose?
Choose the smallest tier that answers your next decision. Start with Performance Triage Lite when the cause is unclear (one page). Choose Prod Readiness Diagnostic for a deeper audit and roadmap across up to 5 pages. Choose Performance Recovery Sprint when you already know the problem and want the highest-impact fixes implemented and validated across up to 7 pages.
04Will optimization break my existing functionality?
That is what the process is built to prevent. Each proposed change connects to a measured bottleneck, only agreed changes are implemented, and performance work has to coexist with your authentication, analytics, accessibility, and product needs. Results are re-tested under comparable conditions before delivery.
05What is not included?
Backend/database optimization, full redesign, new features, security audits, SEO content work, and complex WebGL/runtime architecture unless scoped separately. There is also no Lighthouse 100 guarantee. For example, on an order-management or POS dashboard I cover the agreed frontend flows only; payment, inventory, and order-routing backends are a separate scope.
Ready to start?
Send the URL and the
slowest critical flow.
Include the performance symptom, target device, tech stack, and launch or handoff date.