Which Loop Has Closed? AI Building AI Without the Hype

An AI agent finds a lock that slows an AI service. Is that recursive self-improvement, or good engineering? This story-first lesson separates faster serving, automated training experiments, self-modifying agent software, and autonomous successor-building.

We examine Z.ai's infrastructure report, DeepMind's AlphaEvolve, Karpathy's autoresearch, Sakana's Darwin Godel Machine, Weco's AIDE-squared, and current lab measurements. The counter-case: weak feedback, proxy gaming, diminishing returns, and bottlenecks outside the loop.

Independent synthesis as of October 4, 2026. Lab and practitioner results are attributed claims, not independently reproduced measurements. Direct X posts and three full X Articles were read; this is a targeted sample, not an exhaustive scrape. Narration is AI-generated.

Chapters:

The model and the slow machine

Faster serving is not a smarter model

The overnight experiment worker

When the researcher edits itself

What the frontier labs actually say

The counter-case and the builder's test

Sources:

Z.ai: https://z.ai/blog/glm-built-its-inference-infrastructure

Public FLA accuracy fix: https://github.com/fla-org/flash-linear-attention/pull/1180

DeepMind AlphaEvolve: https://deepmind.google/blog/alphaevolve-a-gemini-powered-coding-agent-for-designing-advanced-algorithms/

Karpathy's reported gains: https://x.com/karpathy/status/2031135152349524125

Autoresearch code: https://github.com/karpathy/autoresearch

Sakana DGM: https://sakana.ai/dgm/

Weco AIDE-squared: https://arxiv.org/abs/2609.26457v1

OpenAI: https://openai.com/index/research-acceleration-view-inside-openai/

Anthropic: https://www.anthropic.com/institute/measuring-pace-of-ai-development

METR: https://metr.org/notes/2026-07-22-economics-of-recursive-self-improvement/

Nathan Lambert: https://www.interconnects.ai/p/where-i-stand-on-rsi

X Articles:

https://x.com/hooeem/status/2030720614752039185

https://x.com/ashpreetbedi/status/2084301728363462919

https://x.com/IntuitMachine/status/2078419526354378975