Jonas Kröger

Frontend Performance Testing in practice

Your local dev environment lies about performance. Learn three practical testing methods to ensure a fast experience for every user.

Frontend Performance Testing in practice
#1about 5 minutes

Why frontend performance is crucial for business and users

Poor performance negatively impacts users with slow internet or low-end devices and directly harms business revenue and signups.

#2about 3 minutes

Understanding key frontend performance metrics and KPIs

Key performance indicators like Time to Interactive and First Contentful Paint translate technical measurements into the perceived user experience.

#3about 2 minutes

Setting aggressive goals for key performance metrics

Establish clear, aggressive targets for metrics like JavaScript bundle size and Time to Interactive to guide optimization efforts.

#4about 3 minutes

An overview of proactive, reactive, and passive testing

Performance testing can be categorized into proactive (during development), reactive (in CI/CD), and passive (continuous monitoring) approaches.

#5about 5 minutes

Proactive testing with dev tools and bundle analyzers

Use browser dev tools for network throttling and tools like Webpack Bundle Analyzer to identify large dependencies during local development.

#6about 11 minutes

Automating reactive performance testing in your CI/CD pipeline

Integrate automated Lighthouse and WebPageTest runs into your CI/CD pipeline to track performance KPIs and enforce budgets on every build.

#7about 3 minutes

Using passive testing for continuous real-user monitoring

Employ external services like New Relic or Calibre to continuously monitor live site performance and gather real-user data over time.

#8about 3 minutes

Key takeaways for building a strong performance culture

Building a performance-focused culture relies on collecting data, automating everything, and fostering developer empathy through practices like "2G Tuesdays".

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