AI-coding tools could be breaking the junior engineer pipeline
Chris Stokel-Walker · 5 October 2026
Read the originalA small Australian study found students coding with AI scored higher but remembered less, and a Manchester engineering head responds by never letting junior engineers work alone.
Researchers at the University of New South Wales gave 55 students three introductory C programming tasks, with either ChatGPT or conventional web search. Chris Stokel-Walker reported the results for LeadDev, a publication for engineering leaders. He also asked Adrian Harwood, head of research software engineering at the University of Manchester, how his department trains juniors who already use AI.
- Students using AI scored 89 percent on the tasks against 69 percent for those using search.
- Two days later, the AI group scored 39 percent on a knowledge test against 52 percent for the search group.
- Students using AI estimated that only 45 percent of the code they submitted was their own.
- In Harwood's department no junior works on a project alone, and senior engineers review their pull requests, including code produced with AI.
Engineering managers may want to judge junior engineers on whether they can explain and test code, not on how much they produce. This is an inference and is not the author's claim. The study was small and involved students rather than working teams, and the article notes both limits.
Teach junior engineers to review what an AI tool produces and to explain why some of its choices may cause problems.
Never assign a junior engineer a project alone, and have a senior engineer review the junior's pull requests, including code written with AI.
Derived by Working Surface from the article; more in the Playbook. Source line: Every person who’s considered junior would never be asked to do a project solo
6 October 2026: as AI agents take on more of the work, teams are writing down expert judgement for agents, keeping juniors next to reviewers, and building views that let a person check agent output.