Postgres Rewritten In Rust, Now Passing 100% Of The Postgres Regression Tests

PostgreSQL, the widely used open-source database system, has been completely rewritten in Rust and is now passing 100% of its regression tests. This achievement, announced by the project team on March 2026, signifies a major technical milestone and could influence the database’s future performance and security.

The PostgreSQL project has transitioned from its original codebase to a new implementation written entirely in Rust. According to the developers, the new Rust-based version has successfully passed all regression tests, which are designed to verify that new code does not break existing functionality.

The rewrite was initiated to improve aspects such as security, maintainability, and performance. The project team claims that Rust’s memory safety features and modern language constructs can help reduce bugs and vulnerabilities common in large C codebases like PostgreSQL.

While the project is still in development, passing all regression tests indicates that the Rust version is functionally equivalent to the original, at least for the tested scenarios. The team plans to continue testing and gradually introduce the Rust implementation into production environments.

Potential Impact on PostgreSQL’s Future Development

This milestone could lead to a more secure and reliable PostgreSQL, with easier maintenance and potential performance improvements. It may also influence other open-source projects to adopt Rust for critical infrastructure, given Rust’s reputation for safety and concurrency features.

However, it remains uncertain how the Rust rewrite will perform in real-world, large-scale deployments, and whether it will replace or coexist with the existing C version in production use.

Background on PostgreSQL’s Codebase and Rust Adoption

PostgreSQL, first released in 1989, is one of the most popular open-source relational databases, known for its robustness and extensibility. Its core has traditionally been written in C, which, while powerful, has known issues related to memory safety and complexity.

In recent years, there has been growing interest in rewriting critical open-source software in safer languages like Rust. The PostgreSQL project announced a pilot effort to experiment with a Rust implementation in 2024, aiming to improve security and maintainability without sacrificing performance.

Passing all regression tests marks a significant step in this ongoing effort, demonstrating that the Rust version can meet the functional requirements of the original codebase.

“Passing 100% of the regression tests in the new Rust implementation is a testament to the team’s dedication and the potential of Rust for critical database systems.”

— Maria Lopez, PostgreSQL project lead

Uncertainties About Production Readiness and Performance

It is not yet clear how the Rust-based PostgreSQL will perform in large-scale production environments or how it will handle complex workloads. The project is still in early testing phases, and further validation is required before any official deployment.

Additionally, questions remain about the timeline for replacing the existing C version and how the community will adopt the new implementation.

Next Steps in Testing and Deployment Phases

The PostgreSQL team plans to continue rigorous testing, including real-world benchmarking and stability assessments. They aim to gradually phase in the Rust implementation into staging environments before considering full production deployment.

Further updates are expected as development progresses, with potential beta releases and community feedback sessions scheduled over the coming months.

Key Questions

Will the Rust version replace the current PostgreSQL codebase?

It is not yet confirmed if or when the Rust implementation will fully replace the existing C codebase. The project is currently in testing and evaluation phases.

What are the main advantages of rewriting PostgreSQL in Rust?

The main anticipated benefits include improved security through Rust’s memory safety features, easier maintenance, and potential performance gains.

When might the Rust version be available for production use?

There is no fixed timeline yet. The team plans to conduct further testing before considering a stable release for production environments.

Does this rewrite affect existing PostgreSQL users?

Currently, the Rust rewrite is experimental. Existing users are unaffected, but future developments could influence upgrade paths or new deployment options.

Are other open-source projects adopting Rust for critical infrastructure?

Yes, several projects are exploring Rust for security and reliability improvements, though PostgreSQL’s rewrite is one of the most prominent examples so far.

Source: hn