David Heinemeier Hansson, creator of Ruby on Rails, says senior developers are the ones who are succeeding in the age of AI agents.
“The most successful and applicable agent acceleration I’ve seen at 37 Signal has been from the most senior people, the people who can validate that what the agent produces is suitable for deployment to millions of people,” Hanson said in an interview on The Pragmatic Engineer podcast/newsletter posted Thursday.
Hanson, co-owner of the software company 37signals, said junior employees don’t yet have the knowledge base to determine whether code created by AI can be trusted.
“Whenever it’s mission-critical for something of this nature, you can’t trust the agents to vet everything, and junior programmers don’t have the ability to understand that,” he said.
At 37signals, Hanson said that senior engineers are much better at working with agents, especially many at once.
“First of all, they can work in parallel with many agents, but they critically examine the quality of the agents’ output and have high confidence that this will work, and redirect if it doesn’t, because this is what made them senior in the first place,” he said.
As an example of what can go wrong, Hanson mentioned the difficulties Amazon encountered with its internal coding tool, Kiro. Business Insider previously reported that Amazon instituted temporary 90-day safety guidelines to ensure that two engineers review their work before implementing changes to the service that could directly impact consumers.
Hanson said in January that while AI shows promise, it is not yet at the level of a junior engineer.
Now, the veteran programmer says, “My daily job is agent-first in everything I do.”