# From Latency to Instant: Modernizing GitHub Issues Navigation Performance

Delays to instant loading: GitHub Issues' innovative approach

- **Source:** [GitHub Engineering](https://github.blog/category/engineering)
- **Published:** 2026-05-14
- **Topic:** [Software & Engineering](https://brifing.si/c/engineering)
- **Original article:** <https://github.blog/engineering/architecture-optimization/from-latency-to-instant-modernizing-github-issues-navigation-performance/>
- **On Brifing:** https://brifing.si/s/62646bdc-d610-4d56-a514-3641de1ee4a2

## The Latency Problem

Navigation delays in GitHub Issues were a significant problem disrupting developers' flow. Even small delays accumulated, reducing efficiency. This issue stemmed from unnecessary data fetching costs.

## New Approach

GitHub focused on the client side to solve the problem. They adopted a strategy of instant rendering with local data and background revalidation. This allowed users to experience faster performance.

## Client-Side Caching

A client-side caching layer backed by IndexedDB was created. This provided faster access to data and reduced unnecessary requests.

## Preheating Strategy

A preheating strategy was developed to increase cache hit rates. This allowed users to access needed data more quickly.

## Service Worker Integration

Service worker integration made cached data usable even during hard navigations. This significantly improved navigation speed.

## Performance Metrics

HPC (Highest Priority Content) metrics were used to measure user-perceived speed. This showed how quickly page content was rendered.

## Navigation Types

Three main navigation types were identified: Hard, Turbo, and Soft navigations. Each was analyzed separately for performance.

## Optimization Results

Optimizations resulted in significant improvements in navigation speeds. Speed became the default for most users.

## Trade-Offs

This approach has some trade-offs. For example, client-side processing increased while server load decreased.

## Next Steps

GitHub continues to work on making speed the default across all navigation paths. This will further enhance user experience.

## Tips for Other Applications

These optimizations are directly applicable to data-heavy web apps. Speed improvements can be achieved without waiting for a full rewrite.

## Web Performance in 2026

By 2026, speed will be a competitive standard. For developer tools, latency will be a measure of product quality.

## Sources covering this story

- https://github.blog/engineering/architecture-optimization/from-latency-to-instant-modernizing-github-issues-navigation-performance/ — 

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_Summary written by Brifing from the original reporting. Copyright in the original article belongs to its publisher; read the full piece at the link above._