Rio 3.5 Open 397B

Rio de Janeiro's municipal IT company published a 403B open MoE as proof a city could build frontier AI. Then the community checked the weights and found a merge. Here is what Rio 3.5 actually is, and whether you should run it.

ZAYA1-8B

Zyphra released ZAYA1-8B, an 8.4B-total / 760M-active Mixture-of-Experts reasoning model under Apache 2.0. It is the first large MoE pretrained, midtrained, and fine-tuned end-to-end on AMD Instinct MI300X, with no Nvidia in the loop. The single-pass math and code scores are strong, the agentic numbers are not, and every benchmark is Zyphra-reported.