Don't be cantankerous.

David Heinemeier Hansson has some advice for engineers as they adjust to AI. Often referred to as DHH, Hansson created the webapp framework Ruby on Rails and has fashioned himself into a software sage.

On Monday, Hansson shared his prediction on X: "The age of agents is going to be amazing for most programmers, but it'll be hard times for the cantankerous ones."

Hansson wrote that special abilities won't save those who are difficult to work with. That would be a dramatic shift in software engineering, where some so-called "cracked" coders can get away with large egos or social awkwardness.

"Best learn some basic people skills," Hansson wrote.

The prediction sparked a conversation among engineers about their social habits and professionalism. One pointed out the irony: agents "don't care how cantankerous you are," but your human coworkers do.

One user wrote a eulogy to the "guy whose whole job security was 'only I know how this works.'"

Dart cofounder Zack Swafford wrote that teams only tolerated bad attitudes because the staffers had "arcane tribal knowledge."

Others questioned how new the change was. People skills have long been valuable, from networking your way into a job to landing that big promotion.

"Been true in every company forever," one X user commented. "Skills get you hired, being easy to work with keeps you around. Agents just make it obvious faster."

Hansson is committed to the future of AI coding. In September, he declared "pencils down" on handwritten code. Hansson explained that writing code was an "exceptional state," performed only when something went wrong with the AI-generated code.

For some engineers, Hansson's post was a vocabulary lesson. "I had to search the definition of 'cantankerous,'" one engineer commented. "First time reading that word."

For the record: cantankerous means bad-tempered and uncooperative.