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World Congress 2022 • Jun 15, 2022

Is your Progressive Web App Lazy? How to read and improve your PWA Performance

Laura Morinigo

Is your PWA secretly lazy? Stop settling for basic responsiveness. Learn to eliminate layout shifts, strip bloated CSS, and master service workers for true offline resilience.

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#1 about 2 min

Introduction to progressive web apps

An overview of why modern web applications need to be responsive, fast, and capable of working offline.

#2 about 3 min

Mandatory technical requirements for PWAs

The three essential components needed to upgrade a standard site into a progressive web application.

#3 about 3 min

Tools for measuring web app performance

Using standard benchmarking environments to identify performance bottlenecks and evaluate application load speeds.

#4 about 3 min

Understanding core Lighthouse performance metrics

How to interpret modern UI performance indicators to understand the actual user experience during initial loading.

#5 about 4 min

Fixing cumulative layout shift with images

Defining specific dimensions and utilizing placeholders for dynamic images prevents visual instability on slow connections.

#6 about 5 min

Optimizing CSS to improve interactivity times

Techniques for reducing render-blocking styles and hunting down unused CSS rules using browser developer tools.

#7 about 3 min

Enhancing perceived load time with splash screens

Configuring the application manifest file to display a splash screen bridges visual gaps for mobile users before complete interactive load.

#8 about 4 min

Implementing offline capabilities using service workers

Strategies for active asset caching, managing unpredictable endpoint failures, and serving customized offline fallback HTML pages.

#9 about 4 min

Reviewing optimization improvements in Lighthouse

A final demonstration showing how applying technical structural changes dramatically boosts overall application metrics for performance.

#10 about 3 min

Handling third-party variability and caching tools

Managing unpredictable dependencies with fallback content and migrating to standard libraries to streamline the development cycle.

Matching moments

1:20 min

Questions on styling extensions and progressive web app potential

Marius Obert Marius Obert · World Congress 2023

1:15 min

Defining progressive web apps and their core advantages

Nico Martin · LIVE

6:13 min

Core capabilities of progressive web applications

Lucien Immink · LIVE

1:29 min

Evaluating progressive web apps for mobile deployment

Mira Jago · World Congress 2021

3:11 min

PWA adoption models and bridging native capabilities

Maxim Salnikov Maxim Salnikov · JS Congress

6:20 min

Enabling offline capabilities and application installation via service workers

Christian Liebel Christian Liebel · World Congress 2022

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Upcoming sessions on this topic

Open session

World Congress 2026 North America

September 24, 2026 · 14:50–15:20

Stage 9

How to generate business value through performance optimizations

Nikolai Sidiropulo

Software Engineer at Meta

Nikolai Sidiropulo
Open session

World Congress 2026 North America

September 24, 2026 · 14:10–14:40

Stage 7

Designing High-Performance AI APIs: Lessons from Serving Millions of Real-Time Requests

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Chief Growth Officer and Americas President of Perfect Corp.

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Open session

World Congress 2026 North America

September 25, 2026 · 14:10–14:40

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Why Your iOS App Feels Broken After an Hour: Diagnosing Long-Session Performance on Real Devices

Vasuki Uday Kiran Vudathala

Staff Performance Engineer at ServiceNow

Vasuki Uday Kiran Vudathala
Open session

World Congress 2026 North America

September 25, 2026 · 15:30–16:00

Stage 6

Small LLM in your Browser: Huge Opportunities for Web Applications

Daniel Ostrovsky

UI/UX Architect at Payoneer | AI Architect | Full Cycle Development Expert | Public Speaker | Open Source Contributor |

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September 25, 2026 · 16:10–16:40

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Speed up your CI/CD pipelines by caching build & runtime artifacts

Thijs Feryn

Technical Evangelist at Varnish Software

Thijs Feryn
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September 24, 2026 · 12:50–13:20

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Architecting Agentic Apps: WebMCP, A2UI, and Agent Experience

Ankita Sood

Sr. Principal Engineer @ Secureworks | Angular GDE

Ankita Sood

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