JavaScript SDK 3.38.3 | Fastly Documentation

Network services
Customize your content delivery.
Full-Site Delivery (CDN)
Streaming Delivery
Purging
Image Optimizer
Security
Protect your services and applications.
Next-Gen WAF
Edge Rate Limiting
Access Control Lists
TLS
Compute
Experiment with Fastly's edge computing platform.
Compute services
Testing and debugging
Edge Data Storage
Quick start
Go from zero to Fastly with these step-by-step guides and tutorials.
CDN getting started guide
Compute getting started guide
Building blocks
Start with the basics and learn how Fastly lets you take advantage of the modern internet.
Services
Core concepts
Web interface guides
Integrations
Find out how Fastly services interoperate with non-Fastly services.
Streaming logs
Logging endpoints
Non-Fastly services
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Tutorials
Step-by-step guides to developing with Fastly
Deliver a site with Fastly
Enhance your UX with Compute
Edge deploy Next-Gen WAF
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Demos
Discover how Fastly can enhance your user experience.
Passwordless auth
Fanout chat
Social sharing cards
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Use Cases
Get solutions to specific problems with curated topics.
Authentication
Geolocation
Personalization
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Code Examples
Try out Fastly code in the browser and easily remix it for your own project.
Geolocation at the edge
Optimize images on the fly
Redirect URLs at the edge
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Starter Kits
Start developing your project immediately with Fastly from a functional template.
Rust default starter
JavaScript default starter
Go default starter
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January 22, 2026

javascript-sdk fixed

Fixed

clean script to include TypeScript output directory (#1270) (015e40c)
pin lol_html to 2.7.0 (#1276) (363550a)
Rename shielding docs (#1272) (e12ab47)
Try and shortcut transform stream reading before doing a regular read (#1279) (6b9b939)

Prior change: JavaScript SDK 3.38.2