Zig Creator Defends Ban on AI Code, Cites Quality and Mentorship Concerns

Andrew Kelley, creator of the Zig programming language, has outlined his reasoning for the project's formal prohibition on AI-generated code submissions in a recent JetBrains interview. Beyond the technical drawbacks, Kelley argues that accepting such contributions undermines the foundational social dynamics of open-source development.

The Quality and Resource Problem#

Kelley pointed to two interconnected issues driving Zig's strict stance. First, AI-generated pull requests consistently fall short of project standards. He described the pattern: contributors paste feedback into an AI system, then repackage the output as original work—a process that wastes reviewer time without producing usable code. The underlying problem is straightforward: "those kinds of contributions are invariably garbage," according to Kelley, with reviewers eventually recognizing that the submitter lacks genuine understanding of what they've contributed.

The second challenge stems from resource constraints. A project's maintainers have finite time for code review, a reality that forces difficult prioritization decisions.

Investment in Real Contributors#

Kelley reframed the issue through what he termed "contributor poker"—strategically allocating review effort toward developers with genuine potential to grow and remain part of the project. AI-using contributors fall into a fundamentally different category: they generate no learning opportunity, provide no pathway to becoming core team members, and consume limited review bandwidth that could benefit actual engineers.

"It's not worth it to invest in them. They're not learning anything. They're not going to join the core team later," Kelley stated, emphasizing Zig's educational mission alongside its technical goals.

A Contrast with Bun's Path#

The approach stands in sharp contrast to Bun, which recently rewrote its entire codebase from Zig to Rust using AI agents for porting, verification, and debugging. Kelley responded with measured criticism, emphasizing that the disagreement reflects "diverging value systems" rather than any technical superiority of one language over another.

Migration Away from GitHub#

Kelley also explained Zig's decision to relocate from GitHub to , a German nonprofit platform. The move was prompted by persistent infrastructure failures—GitHub Actions continuous integration pipelines repeatedly became unreliable. Beyond technical stability, Kelley expressed philosophical alignment with nonprofits over venture-backed platforms, which he characterized as perpetually chasing growth and quarterly gains. "Nonprofits are just trying to keep doing what they're doing, and that stability is what I want," he said.