LiteSpeed Enterprise Developer Guide for WordPress -- WP Pro Host

Q: How do I purge the LiteSpeed cache via WP-CLI?

Run `wp litespeed-purge all` to purge all cached pages, or `wp litespeed-purge url https://yourdomain.com/specific-page/` to purge a specific URL. To pre-warm the cache after a deployment, use `wp litespeed-crawler start`. These commands are useful in automated deployment scripts to ensure visitors immediately receive fresh cached content after code changes.

Q: What is ESI (Edge Side Includes) in LiteSpeed?

Edge Side Includes (ESI) allows parts of a cached page to be rendered dynamically while the rest is served from cache. This is useful for pages that are mostly static but contain per-user elements such as a cart count, logged-in user widget, or personalised recommendations. LiteSpeed Cache WordPress plugin exposes ESI support through per-widget and per-block caching settings, allowing granular cache control without disabling caching for the entire page.

Q: Does LiteSpeed support HTTP/3?

Yes, LiteSpeed Enterprise supports HTTP/3 and QUIC natively, and it is active by default on WP Pro Host. HTTP/3 provides connection multiplexing without head-of-line blocking, 0-RTT connection resumption for returning visitors, and better performance on lossy connections such as mobile networks. Verify HTTP/3 is active for your site with: curl --http3 -I https://yourdomain.com

LiteSpeed vs Nginx: What Developers Need to Know

Most WordPress hosting documentation assumes Nginx or Apache. LiteSpeed is architecturally different and requires different mental models for caching, rewrite rules, and PHP configuration.

LiteSpeed uses its own web server configuration format (.htaccess directives work but LiteSpeed has additional directives), its own PHP handler (LSAPI instead of PHP-FPM), and a native caching system (LiteSpeed Cache / LSCWP) that operates at the web server level rather than the PHP level.

LSAPI vs PHP-FPM

LiteSpeed LSAPI is a PHP handler purpose-built for LiteSpeed. Compared to PHP-FPM, LSAPI uses less memory per worker, handles concurrent requests more efficiently, and restarts PHP workers faster after errors. For a WordPress site with 8 PHP workers, LSAPI will typically handle more concurrent requests with lower peak memory than the equivalent PHP-FPM configuration.

From a developer perspective, LSAPI behaves identically to PHP-FPM for application code — the difference is entirely at the infrastructure level. Your PHP code, plugins, and themes don’t need modification to benefit.

LiteSpeed Cache: Server-Level Caching

LiteSpeed Cache (LSCWP) is a WordPress plugin that communicates with the LiteSpeed web server to enable server-level full-page caching. Unlike W3 Total Cache or WP Super Cache, which write static files and serve them via PHP or .htaccess rules, LSCWP serves cached pages directly from the web server — bypassing PHP entirely.

This means cached page requests don’t consume a PHP worker and don’t touch the database. Response time for a cached page is in the microsecond range, not milliseconds.

Cache exclusion rules

LiteSpeed Cache respects standard WordPress cookie-based exclusions — logged-in users, WooCommerce cart sessions, and checkout pages are excluded automatically when the WooCommerce integration is configured correctly. You can add custom exclusion rules via the LSCWP plugin settings or via .htaccess directives:

RewriteRule .* - [E=Cache-Control:no-cache]

For custom post types or query strings that should bypass cache, use LSCWP’s “Do Not Cache” rules rather than disabling caching globally.

HTTP/3 and QUIC

LiteSpeed Enterprise supports HTTP/3 and QUIC natively. From a developer perspective, this means:

Connection multiplexing without head-of-line blocking (unlike HTTP/2)
0-RTT connection resumption for returning visitors
Better performance on lossy connections (mobile networks)
No configuration required — HTTP/3 is active by default on WP Pro Host

Verify HTTP/3 is being used for your site via curl: curl --http3 -I https://yourdomain.com. You should see HTTP/3 200 in the response.

ESI (Edge Side Includes)

LiteSpeed supports ESI, which allows parts of a cached page to be dynamic while the rest is served from cache. Useful for pages that are mostly static but contain a logged-in user widget, a shopping cart count, or similar per-user elements.

LSCWP exposes ESI support through its widget and block caching settings. Enable per-block caching in the LSCWP plugin settings and tag individual widgets or shortcodes for separate cache handling.

Rewrite Rules

LiteSpeed uses .htaccess for rewrite rules and is Apache-compatible for standard WordPress permalink structures. WordPress’s default .htaccess rewrite rules work without modification. LiteSpeed-specific directives use the RewriteRule syntax with additional LiteSpeed environment variables for cache control.

PHP Configuration

On WP Pro Host via Enhance CP, PHP settings (memory limit, execution time, upload size, PHP version) are configurable per site via the control panel or via .user.ini files in the site root. WP-CLI is available via SSH for site management tasks.

Recommended php.ini values for a WooCommerce site:

memory_limit = 256M
max_execution_time = 60
upload_max_filesize = 64M
post_max_size = 64M
max_input_vars = 3000

QUIC.cloud CDN Integration

QUIC.cloud is the CDN built specifically for LiteSpeed. Unlike generic CDNs that treat WordPress as a black box, QUIC.cloud understands WordPress cache tags — it knows which cached pages to invalidate when a post is published, a product changes, or a menu is updated.

From a developer workflow perspective: after deploying changes that affect cached content, purge via WP-CLI (wp litespeed-purge all), via the LSCWP plugin admin, or via the QUIC.cloud API. Smart purging invalidates only affected pages rather than flushing the entire cache.

Frequently Asked Questions

What is the difference between LiteSpeed and Nginx for WordPress?

LiteSpeed uses its own PHP handler (LSAPI instead of PHP-FPM), a native server-level caching system, and supports HTTP/3 and QUIC natively. LSAPI uses less memory per worker than PHP-FPM and handles concurrent requests more efficiently. LiteSpeed is Apache .htaccess-compatible so standard WordPress rewrite rules work without modification, but adds its own directives for cache control.

How does LiteSpeed Cache work differently from other WordPress caching plugins?

LiteSpeed Cache (LSCWP) serves cached pages directly from the web server, bypassing PHP entirely. Unlike W3 Total Cache or WP Super Cache, which write static files served via PHP, LSCWP operates at the server level — cached page requests consume no PHP worker and perform no database queries. Response times for LiteSpeed-cached pages are in the microsecond range rather than milliseconds.

How do I purge the LiteSpeed cache via WP-CLI?

Run wp litespeed-purge all to purge all cached pages, or wp litespeed-purge url https://yourdomain.com/page/ to purge a specific URL. To pre-warm the cache after deployment, use wp litespeed-crawler start. These commands are well suited to automated deployment scripts to ensure visitors receive fresh content immediately after code changes.

What is ESI (Edge Side Includes) in LiteSpeed?

ESI allows parts of a cached page to be rendered dynamically while the rest is served from cache. Useful for pages that are mostly static but contain per-user elements such as a cart count or logged-in user widget. LiteSpeed Cache exposes ESI support through per-widget and per-block caching settings, enabling granular cache control without disabling caching for the entire page.

Does LiteSpeed support HTTP/3?

Yes. LiteSpeed Enterprise supports HTTP/3 and QUIC natively, and it is active by default on WP Pro Host. HTTP/3 provides connection multiplexing without head-of-line blocking, 0-RTT connection resumption for returning visitors, and better performance on mobile networks. Verify with: curl --http3 -I https://yourdomain.com