What is harness engineering, and why does it matter?
'Harness Engineering' - another AI buzzword. What is it, what does it do, does it matter?
AI coding tools are creating a new category of engineering risk. Here's what I'm seeing.

AI coding tools are creating a new category of engineering risk. Here's what I'm seeing.
This has reshaped how my teams work. PMs now prototype with live code instead of writing detailed specs. Engineers spend more time on architecture and testing criteria, less time coding. Our PM-to-developer ratio shifted from 1:10 to 1:5 for some teams. Everyone's role is changing.
The problem: AI reduces the cost of writing code. It does not reduce the cost of managing complexity.
Here are 8 traps emerging as organizations adopt AI-assisted development:
Coding becomes the fastest step. Validation becomes the bottleneck. Teams produce code faster than they can safely review it.
AI turns vague ideas into polished code. The output looks credible, which makes bad requirements harder to catch.
AI optimizes locally, not globally. Authentication, logging, error handling, each implemented differently. Components work. The system becomes harder to evolve.
AI learns from existing code, including insecure patterns. The danger is the speed at which vulnerabilities propagate.
Teams ship code they didn't reason through. It works until a production incident. Then no one can explain the system's behavior.
AI optimizes for the happy path. Worse: AI-generated tests often mirror the implementation. Bug in code, bug in test. Both pass.
AI lowers the cost of creating services. Not maintaining them. Every component adds long-term obligations.
AI changes what engineers practice daily. Systems thinking and debugging become more important, but get less exercise.
The core pattern: The companies that win won't generate code fastest. They'll manage complexity best.
AI changes the economics of code generation. It doesn't change the physics of complex systems.
I'm working on a deeper write-up with mitigation strategies for each trap. Will share in the comment section once it's ready, follow me & save this post if you want the follow-up.