AI Code Review: The New Senior Engineer Job

Canva CTO Reveals: Senior Engineers Now Spend Most Time Reviewing AI-Generated Code

Canva's chief technology officer, Brendan Humphreys, has disclosed a major shift in engineering roles. Senior engineers at the graphic design giant now dedicate the majority of their time to reviewing code produced by AI agents, marking a profound change in how software is developed.

AI Agents Transform Engineering Workflows at Canva

Engineering teams at Canva use AI agents by providing detailed instructions for tasks that run autonomously, often overnight. By morning, substantial work is complete, delivering hours of autonomous effort that meets high standards after a human review. Humphreys describes these results as frequently impressive, yet emphasizes the essential human touch to ensure quality.

This approach redefines coding roles. Senior engineers focus primarily on review duties, verifying AI outputs, guiding agents along planned paths, and owning the final products. They still invest time in defining problems, translating vague requirements into production-ready specifications, which demands precise articulation and deep domain expertise.

Productivity Boosts and Real-World Impacts

Tools like GitHub Copilot have increased senior engineers' productivity by about 30%, enabling more pull requests to merge weekly. Canva encourages widespread AI experimentation, with 50% of engineers using these tools daily and a goal to reach 80% by late 2025. Engineers who master prompting demonstrate both strengths and limitations, always with peer reviews that incorporate AI for code comprehension.

• AI agents lower technical barriers, allowing non-engineers like CEOs to request changes, such as font updates, which engineers quickly approve.
• Senior engineers supervise AI like junior employees, providing clear instructions, success criteria, and examples for optimal results.
• AI-assisted code review is emerging to handle increased volumes from simple prompts generating extensive code.

Challenges for Junior Engineers and Industry-Wide Concerns

New graduates face hurdles despite AI familiarity. They lack domain knowledge to discern good code from bad, making tools potentially dangerous without oversight. Canva counters this with extended mentoring from seniors, who increasingly review both AI-generated and junior-produced code. A custom GPT, trained on 300 peer-reviewed articles, aids juniors like a human mentor.

IT leaders express wariness, with 95% concerned about AI code risks and 93% mandating reviews before production. Governance and human oversight remain critical to maintain enterprise-grade quality, security, and best practices.

Preparing Humans for the AI Era

Canva fosters an AI-native culture through companywide experimentation, hiring for relevant skills, and strict human-in-the-loop processes. Leaders view AI as a task transformer, turning hours-long efforts into minutes with accuracy, while humans guide, assess, and own outputs. Senior review roles, long-standing, have amplified importance in AI coding.

Conclusion: The Future of Engineering

AI is reshaping software development, boosting efficiency while elevating the need for expert oversight. As Canva demonstrates, thriving engineers leverage AI to amplify their capabilities, not replace them. This evolution promises faster innovation, provided human mastery steers the course.