Case Study: Mixpanel speeds AI-generated PR reviews with Greptile

Mixpanel reviews 2,900 PRs a month with Greptile

Mixpanel, an analytics company with a complex codebase, faced the challenge of integrating AI-generated code, as nearly all of their pull requests (PRs) were being written by AI agents like Claude Code and their internal agent, TAL. This created a bottleneck, as human reviewers were often reviewing PRs that weren't ready, wasting time on finding basic flaws. To address this, they sought an automated code review solution and evaluated building their own tool and other providers. The engineering team chose the vendor Greptile to implement an AI-powered code review system.

The solution from Greptile provided fast, cost-effective reviews that could understand context across the entire codebase, catching critical issues other tools missed. The results were significant, with Greptile reviewing approximately 9,300 PRs per month and surfacing around 4,800 issues. This allowed human reviewers to focus on the intent of changes rather than hunting for bugs. Mixpanel found Greptile to be so integral that it became a key part of their agent-driven workflow, reducing costs and improving efficiency.

Mixpanel