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I am looking for a short story I read online a few years ago, about artificial lifeform, with a hard sci-fi taste.
A couple of software engineers were trying to identify a strange program behavior on a new system in development, but digging through the outer layers of software source didn't explain the seemingly random issues they observed. After hours of debugging, they identified unexpected output at the compiler level.
One of the developers manages to craft a workaround, only to see additional issues appear around the fixes, and he begins to fear a backdoor might have been planted in the compiler, which seemed tainted much like the Ken Thompson hack. As this might eventually jeopardize the entire project, they spend more and more time on the issue itself, but as time passes, the deeper bugs they discover and fainter they become.
In the end, it seems like some artificial intelligence tried to emulate evolutionary pressure by establishing a form of communication channel, and having groups of humans around the world fixing the most obvious software outer layers. Even computer-assisted hardware design could be contaminated at this time, but in such complex a way they might go undetected for a long time, now adapted to the silicon environment.
I've been literally searching this story for months, and begin to believe I dreamt of it and should start writing myself.