Query and fragment caching for WordPress and WooCommerce
QuantumCache runs inside PHP, caches database query results and reusable rendered fragments, and reduces repeat work on requests that still reach WordPress. Free is built for standard public WordPress acceleration. Pro extends the same engine for WooCommerce-aware behavior, controlled logged-in caching, metrics, and CDN-aware purges.
What QuantumCache Is
QuantumCache is a server-side query and fragment cache for WordPress. It runs inside PHP, reuses database query results and rendered fragments, and reduces the amount of work WordPress has to repeat on later requests. It is designed for requests that still reach the application layer, including standard WordPress pages, WooCommerce catalog pages, page-cache misses, and selected logged-in traffic when Pro is configured.
QuantumCache uses Redis when available and can fall back to its own MySQL-backed store when Redis is unavailable. It complements a page cache or CDN instead of replacing either layer.
%% DIAG-001 — Request Stack / System Positioning Diagram
%% Source: qc_source_of_truth.md §7
%% QuantumCache does not replace CDN or page cache — it complements them.
flowchart TD
CLIENT["Client"]
CDN["CDN\n─────────────────────\nRequests absorbed here\nnever reach QC"]
PAGECACHE["Page Cache\n─────────────────────\nRequests absorbed here\nnever reach QC"]
PHP["PHP / WordPress + QuantumCache\n─────────────────────────────────────────────\nQC operates here — query and fragment caching\nduring PHP execution\nBenefits requests that reach PHP:\nlogged-in users (Pro) · dynamic Woo endpoints\npage cache misses · sites without a page cache"]
DB["Database"]
CLIENT -->|"request"| CDN
CDN -->|"cache miss / uncacheable"| PAGECACHE
PAGECACHE -->|"cache miss / uncacheable"| PHP
PHP -->|"DB query (on cache miss)"| DB
DB -->|"result"| PHP
PHP -->|"response"| PAGECACHE
PAGECACHE -->|"response"| CDN
CDN -->|"response"| CLIENT
note1["QuantumCache does not replace CDN or page cache — it complements them"]
style CLIENT fill:#f5f5f5,stroke:#aaa
style CDN fill:#dbeafe,stroke:#3b82f6
style PAGECACHE fill:#dbeafe,stroke:#3b82f6
style PHP fill:#dcfce7,stroke:#16a34a
style DB fill:#f5f5f5,stroke:#aaa
style note1 fill:#fffbeb,stroke:#d97706,color:#92400e
style note2 fill:#f8f8f8,stroke:#ccc,color:#555 Requests absorbed by the CDN or page cache never reach QuantumCache. QC benefits requests that complete a full trip to the PHP application layer.
QuantumCache is not a page cache — it does not store or serve complete HTTP responses. It is not a CDN — it does not operate at the network edge. It operates below both in the request stack, reducing the cost of PHP execution for requests that reach it.
Shared Foundation
Free and Pro share the same underlying cache engine. The difference is not a separate product line. Pro extends the same model for more complex WooCommerce and logged-in behavior.
Query cache
Caches eligible front-end query results so repeat requests can skip repeating the same main query work.
Fragment cache
Captures reusable rendered output during PHP execution so the same fragment does not need to be rebuilt on later requests.
Redis when available
QuantumCache prefers Redis and can fall back to its own MySQL-backed tables when Redis is unavailable.
CLI and diagnostics
Free includes debug headers, purge tools, and wp quantumcache status / wp quantumcache flush.
Pro adds optional metrics and CDN-aware purge integrations.
Pro extends the same engine with WooCommerce-aware behavior, optional logged-in caching for allowlisted roles, Prometheus-compatible metrics, and CDN cache-tag integrations for Cloudflare, Fastly, and LiteSpeed.
Free for Public WordPress, Pro for More Complex Behavior
Free covers public WordPress acceleration. Pro extends the same core for WooCommerce-aware and controlled logged-in behavior.
QuantumCache Free
- Same shared query and fragment cache engine
- Built for anonymous front-end WordPress traffic
- Redis as preferred store with MySQL fallback
- Debug headers, purge tools, and WP-CLI status / flush
- WooCommerce pages can still benefit as general public content
No WooCommerce-specific key variation, bypass rules, product invalidation, or logged-in caching controls.
QuantumCache Pro
- Everything in Free
- WooCommerce-aware cache variation, archive TTLs, and fragment coverage
- Bypass rules for cart, checkout, account, Woo AJAX, and session or cart cookies
- Product-aware invalidation for catalog and related WooCommerce changes
- Optional logged-in caching for allowlisted roles with a separate TTL
- Prometheus metrics plus CDN tag / purge integrations
Pro is not "faster Free." It is the same engine extended for correctness, control, and operations on more complex WordPress and WooCommerce sites. Compare tiers →
Benchmark Detail Lives on the Benchmarks Page
QuantumCache has published benchmark data for standard WordPress routes and WooCommerce routes, but the homepage keeps that material brief. Results vary by route, warmup state, backend, and site architecture.
Review the full benchmark page for route-by-route numbers, methodology, and cold-path caveats rather than relying on a homepage summary. See benchmarks →
Where to Go Next
Start with features, validate with benchmarks, compare tiers, or move straight to implementation details.