GLM-5.3-Flash Architecture Notes

The Ox Alpha LLM has been identified as GLM-5.3-Flash, a new model from Zhipu AI that introduces a hybrid attention architecture combining 34 Kimi Delta Attention layers and 11 Multi-head Latent Attention/DeepSeek Sparse Attention layers, and scales down its sparse MoE backbone from 744B-A40B to 320B-A18B. The model also features a DeepSeek V4-style mHC residual path with four parallel streams and a native vision encoder, according to architecture notes by Sebastian Raschka.

GLM-5.3-Flash Architecture Notes Now we know: The popular Ox Alpha LLM was GLM-5.3-Flash… Compared to GLM-5.2, this new GLM-5.3-Flash model uses: - a Kimi Linear-style 3:1 super hybrid attention pattern with 34 Kimi Delta Attention layers KDA and 11 Multi-head Latent Attention MLA / DeepSeek Sparse Attention DSA layers; - a scaled-down GLM-5.2-style sparse MoE backbone, going from 744B-A40B to 320B-A18B; - a DeepSeek V4-style mHC residual path with four parallel streams; - plus a native vision encoder not shown . I called it a “super hybrid” above because both KDA and MLA/DSA are “efficient” components. E.g., Kimi only uses KDA + full attention MLA, DeepSeek V3.2 uses DSA + full attention MLA. PS: I’m sorry for the excessive tech jargon. Explainers on all these components MLA, DSA, KDA, mhC, etc. in my LLM Architecture Gallery /llm-architecture-gallery/ . PPS: Haha, maybe justification for getting that pricey Mac Studio M5 Ultra 256 GB / 512 GB to run this locally… Source: website version of my Substack note https://substack.com/@rasbt/note/c-323088504 . Read Next How Claude's Text Watermarking Works Short illustration of how Claude's text watermarking is supposed to work based on Anthropic's released materials. /blog/2026/claude-text-watermarking.html Build a Reasoning Model From Scratch Is Now on Amazon Short note on the Amazon availability of Build a Reasoning Model From Scratch and a warning about counterfeit black-and-white copies sold through Amazon In /blog/2026/build-a-reasoning-model-from-scratch-on-amazon.html Muse Glimmer 30B Architecture Notes Short architecture note on Meta Muse Glimmer 30B, including gated local and global GQA, KV-cache efficiency, and release-time benchmark comparisons. /blog/2026/muse-glimmer-30b-architecture-notes.html