RenderloriaRender · Measure · Refine Request a rendering review

Frontend rendering and performance engineering

Faster Renders. Smoother Interactions.

Renderloria helps product and engineering teams in Canada work out why their apps paint late and answer taps slowly, then plan fixes inside the framework they already use, whether that is React, Next.js, Vue, Nuxt, Svelte or Angular.

Request a rendering review See how a review works

  • Hydration and JavaScript cost
  • INP and long tasks
  • Rendering strategy fit
Illustrative dashboard, sample numbers. It shows the kind of view we build during a review, not a measurement of any real site.

Our services

Rendering work, from first byte to next paint

Each service looks at a different part of the path from server response to an interactive screen. A rendering analysis is the natural starting point, and its findings show which of the others you need.

Explore all services

How it works

A four-step review you can follow

See the detailed process
  1. 01

    Measure and trace

    We start from your field data where it exists, then record traces on throttled devices to see which scripts, renders and layouts fill the main thread.

  2. 02

    Find the causes

    Each slow moment gets a named cause, such as a hydration pass, a long event handler or a late hero image, with the evidence beside it.

  3. 03

    Plan the changes

    You get a ranked list of changes written for your framework and team, with the trade-offs and the risk of each one spelled out.

  4. 04

    Retest and compare

    After your team ships changes, we compare traces and, once enough visits have passed, field data, so you can see whether the work moved the numbers.

Free tools

Try the ideas in your browser

Three small tools that run entirely on this page. They teach and plan; none of them visits or scores your site.

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  • Rendering pipeline visualizer

    See how five rendering strategies play out on three device profiles.

    Visualize

  • Long-task budget planner

    Estimate INP phases on slower devices from timings you measured.

    Estimate

  • Rendering optimization planner

    Answer three questions and download an ordered plan as a text file.

    Generate a plan

Illustrative example

What a before and after report looks like

The panels on this page use invented numbers to show the format of our reports. No client stands behind them.

In this invented example the before panel describes a route that server-renders quickly but then hydrates every component at once, so the main thread stays busy just as people start tapping. The after panel describes the same route once below-the-fold widgets hydrate on view and a heavy filter handler is split into smaller pieces.

Real reports carry the traces, the field data window and the exact build that was measured, because a number without its conditions tells you very little.

See illustrative examples

Before

Lab score
42
LCP
4.8 s
INP
320 ms
CLS
0.25

Hydrates everything at once

After

Lab score
98
LCP
1.1 s
INP
76 ms
CLS
0.02

Server-rendered, islands hydrate on view

Illustrative dashboard, sample numbers. These two panels are invented to show how a review reports change; they are not results from a client.

Common questions

Questions a product team might ask first

We have no client quotes to show yet, so here are questions an engineering lead might fairly ask before a review, with straight answers.

  • Our Lighthouse score is fine, so why do users say the app feels slow?

    Lighthouse runs one simulated load in a lab. Interaction to Next Paint comes from real visits and every tap or key press in them, so an app can score well in the lab and still respond late in the field. We compare both before deciding where to look.

  • Do we have to rewrite the app or change frameworks?

    Usually not; the common fixes are changes inside your current stack: hydrating less at once, moving work off the critical path, splitting long handlers or adjusting how a route renders. If a rendering change is worth it, we explain the cost first.

  • Can you work with our developers rather than around them?

    Yes. Findings are written for engineers, with file paths and trace screenshots where we have access, and we are happy to review pull requests that come out of the plan.

Ready when your team is

Plan your rendering review with us

Tell us about your app, its framework and where it feels slow. We reply with questions and a fixed written quote.

Start a conversation
  • Fixed written quote
  • Written findings
  • No obligation