Phrust Documentation

Phrust is a Rust implementation of a PHP 8.5-compatible engine. It currently provides a developer CLI, an integrated HTTP server, PHPT compatibility tooling, and the engine layers needed to compare behavior with a pinned PHP reference.

Phrust is useful for engine development and compatibility work. It is not a drop-in production PHP runtime, Zend extension ABI, FPM replacement, Opcache replacement, or production JIT.

Users

Start here to run PHP code, try the server, or understand current compatibility.

• Getting started
• CLI usage
• Web server
• Compatibility
• Switching from PHP
• PHP user interface matrix

Contributors

Start here when changing the engine, tests, compatibility fixtures, or docs.

• Contributor index
• Contributor guide
• Validate a change
• Work with PHPT
• WordPress smoke workflow

Architecture

These pages explain the implementation structure and accepted boundaries.

• Architecture index
• ADRs
• Lexer architecture
• Parser architecture
• Semantic frontend architecture
• Runtime and VM
• Standard library
• Server architecture
• Performance

Reference

Use these documents for current status, compatibility contracts, and machine policy summaries.

• Reference index
• PHP compatibility target
• Known-gap manifests
• PHPT status
• Performance status
• Runtime known gaps
• Standard library known gaps
• Server known gaps
• API facades

Documentation Policy

Human-facing docs describe stable behavior, accepted architecture, current compatibility posture, and reproducible workflows. Local benchmark outputs, profiler captures, PHPT run reports, and generated JSON/JSONL reports belong under target/ unless a tool explicitly consumes a committed manifest.

research/ contains exploratory notes and implementation options. Research docs are not accepted project contracts unless an ADR or owning architecture page adopts them.