Can you improve Core Web Vitals?

Yes. I identify the causes behind LCP, CLS, and INP issues and make targeted frontend and Next.js improvements.

Will performance work change the design?

Usually no. The goal is to preserve the experience while improving loading, rendering, and responsiveness.

How do you find what is actually slow?

By measuring before changing anything. That means field data from real users alongside lab profiling, because the two often disagree. Most sites have one or two dominant bottlenecks — usually payload size, images, or a render path — and fixing those beats a long list of micro-optimizations.

What if my performance problem is in the backend, not the frontend?

Then I will tell you that rather than optimizing around it. Slow API responses, missing database indexes, and N+1 queries all show up as frontend slowness but cannot be fixed in the frontend. Identifying the real cause is part of the audit.

Will you need to change how the site is built?

Sometimes, and I flag it before starting. Bundle size and image delivery improvements are usually contained. Moving rendering strategy, replacing a heavy dependency, or restructuring a data-fetching pattern are larger changes, and they get scoped separately so you can decide whether the gain justifies the work.

Can you set up ongoing performance monitoring?

Yes. Without monitoring, performance regresses quietly with the next few releases. I can set up field measurement and budgets so a regression is visible in CI or in your dashboard rather than discovered months later.

Performance

Web Performance Optimization for React & Next.js

Improve slow web applications before they cost you users, conversions, and search visibility. I help React and Next.js products load faster, feel smoother, and perform better across real devices.

Tell me about your project Prefer a call? Book 30 minutes

Work directly with me. Clear scope before a quote. Reply within one working day.

A simple first step

Tell me about your product.

A few sentences are enough. Share what you want to build, who it is for, and any deadline. You don't need a finished specification.

01I reply within one working day.
02We clarify the first release, priorities, and any unknowns.
03You get a proposed scope and next step before committing to a build.

Free initial conversation · No obligation

Prefer email or a call?

contact@sameersabir.dev Book a free 30-minute call

Overview

Performance work is most effective when it targets real bottlenecks: bundle size, images, rendering behavior, data fetching, caching, and user-perceived speed.

Everything starts with measurement, using field data from real users alongside lab profiling — the two frequently disagree, and field data is the one that reflects your actual audience and their devices. Most sites have one or two dominant bottlenecks rather than a long tail of small ones, so finding them is worth more than applying a generic checklist.

The usual wins are unglamorous: shipping less JavaScript, serving appropriately sized modern images, fixing layout shift from unsized media, and removing render-blocking work from the critical path. Where the cause turns out to be backend latency or an N+1 query, I will say so rather than optimizing around it — that problem cannot be fixed in the frontend, and identifying it correctly is part of the audit. I also set up ongoing measurement where it is wanted, because performance regresses quietly across releases unless something is watching for it.

What I offer

Core Web Vitals review and optimization
Next.js rendering and caching improvements
Image, font, and asset optimization
Bundle analysis and code splitting
React rendering and state update cleanup

Key deliverables

A prioritized performance audit with the issues that matter most to real users
Targeted improvements for loading speed, layout stability, responsiveness, and bundle weight
Before-and-after notes that explain what changed and how to keep the app fast

How I approach it

Measure the current experience with Lighthouse, browser tooling, and code inspection
Fix the highest-impact bottlenecks in rendering, assets, data fetching, and bundles
Re-test the changed pages and document practical maintenance guidance

Business outcomes

Faster perceived loading for users on real devices and slower networks
Improved Core Web Vitals signals for SEO, quality, and conversion confidence
A clearer understanding of what was slowing the app down and how to avoid regression

Engagement options

Focused performance audit and implementation sprint
Core Web Vitals improvement for a high-value page or app flow
Ongoing frontend optimization during a larger product build

Ideal for

Sites with poor Lighthouse or Core Web Vitals scores
SaaS apps that feel slow after adding features
Marketing and portfolio sites that need better SEO performance

FAQs

Can you improve Core Web Vitals?: Yes. I identify the causes behind LCP, CLS, and INP issues and make targeted frontend and Next.js improvements.
Will performance work change the design?: Usually no. The goal is to preserve the experience while improving loading, rendering, and responsiveness.
How do you find what is actually slow?: By measuring before changing anything. That means field data from real users alongside lab profiling, because the two often disagree. Most sites have one or two dominant bottlenecks — usually payload size, images, or a render path — and fixing those beats a long list of micro-optimizations.
What if my performance problem is in the backend, not the frontend?: Then I will tell you that rather than optimizing around it. Slow API responses, missing database indexes, and N+1 queries all show up as frontend slowness but cannot be fixed in the frontend. Identifying the real cause is part of the audit.
Will you need to change how the site is built?: Sometimes, and I flag it before starting. Bundle size and image delivery improvements are usually contained. Moving rendering strategy, replacing a heavy dependency, or restructuring a data-fetching pattern are larger changes, and they get scoped separately so you can decide whether the gain justifies the work.
Can you set up ongoing performance monitoring?: Yes. Without monitoring, performance regresses quietly with the next few releases. I can set up field measurement and budgets so a regression is visible in CI or in your dashboard rather than discovered months later.