pgrust: The Open-Source Project Rewriting PostgreSQL in Rust

Rewriting a Database Giant: Meet pgrust PostgreSQL is the bedrock of modern application development. It is incredibly stable and feature-rich, but it is built on a C codebase that started in the 1980s. In systems programming, legacy C architectures carry memory-safety risks and make core changes difficult. pgrust is an experimental open-source project that aims to rewrite the entire PostgreSQL database engine from scratch in Rust. The project recently hit a historic milestone: it now passes 100% of the official PostgreSQL 18.3 regression test suite (over 46,000 test queries). What is pgrust? pgrust is a native reimplementation of the Postgres query execution and storage layers. Unlike other projects that wrap Postgres or write extensions, pgrust is a complete rewrite of the database core itself. Crucially, it is disk-compatible with PostgreSQL 18.3, meaning it can boot up and read from an existing Postgres database directory on your machine. Key Technical Improvements By shifting from C to Rust, pgrust introduces several modern engineering improvements: 1. Memory Safety Rust’s strict compiler guarantees eliminate major classes of security vulnerabilities (like buffer overflows and dangling pointers) that frequently patch legacy C databases. 2. Thread-Per-Connection Model Standard PostgreSQL uses a "process-per-connection" architecture, which consumes a lot of system memory. pgrust changes this to a "thread-per-connection" model, drastically reducing the overhead of open connections. 3. Massively Improved Performance Because of its optimized query engine and thread-based architecture, early benchmarks show: 50% faster execution on standard transaction workloads. Up to 300x faster execution on analytical workloads. Built with an "AI Agent Factory" Rewriting a database with millions of lines of code is a monumental task. The authors of pgrust accomplished this by setting up an automated pipeline of concurrent AI coding agents. The agents were tasked with explaining leg