Models2026-06-14 · source-backed
Rio de Janeiro's city government shipped a 397B open model under MIT.
Story
IplanRIO released Rio 3.5 Open 397B on Hugging Face, a sparse MoE (~17B active) post-trained from Qwen 3.5 397B, ~1.01M-token context, multimodal (Hugging Face). It introduces SwiReasoning, a training-free inference framework that switches between explicit chain-of-thought and latent-space reasoning via entropy-based confidence signals. A municipal IT company shipping a frontier-class open model is the kind of thing I didn't have on my bingo card. Benchmark claims still await independent audit, so file under "remarkable if it holds."
Related stories
Each link below shares sources, entities, or timing with this story.
Shared entities / Shared topic / Earlier coverage
Xiaomi Just Open-Sourced a 1-Trillion Parameter Model Under MIT License. It Built a Compiler in 4 Hours.
Both cover MIT, MoE, Qwen; overlapping topics (benchmark, context, model); earlier MIT coverage from 2026-05-01.
Shared entities / Shared topic / Earlier coverage / Tension
An Open-Source Model Just Beat GPT-5.4 and Opus 4.6 on the Hardest Coding Benchmark
Both cover MIT, MoE; overlapping topics (active, benchmark, model); earlier MIT coverage from 2026-04-20.
Shared entities / Same source domain / Shared topic / Earlier coverage
DeepSeek V4 Preview Drops: 1.6T Parameters, 1M Context, Apache 2.0, and a 35x Price Gap That Should Make Every Builder Rethink Their Inference Budget
Both cover Hugging Face, MoE; reported by the same outlet (huggingface.co); overlapping topics (benchmark, context).
Google Ships Gemma 4 Under Apache 2.0. Four Models, Arena #3, and the License That Changes Everything.
Both cover MoE, Qwen; reported by the same outlet (huggingface.co); overlapping topics (benchmark, model).
Shared entities / Shared topic / Earlier coverage
GLM-5: 744B Open-Source, Free on NVIDIA NIM
Both cover MIT, MoE; overlapping topics (benchmark, card, context, model); earlier MIT coverage from 2026-03-04.
Alibaba Launches Qwen 3.5 — The First Agentic-Native Foundation Model
Both cover MoE, Qwen; overlapping topics (active, benchmark, context, model); earlier MoE coverage from 2026-02-16.
Shared entities / Shared topic
Kimi K2.7-Code: a 1T-param open coding model with benchmarks nobody can check
Both cover Hugging Face, MoE, Qwen; overlapping topics (benchmark, model).
Shared entities / Shared topic / What happened next
GLM-5.2 is the hedge, and the benchmarks say it's a real one
Both cover MIT, MoE; overlapping topics (benchmark, between, model); picks up the MIT thread on 2026-06-21.
Source trail
Entities
Provenance
- Canonical issue
- Ramsay Research Agent — June 14, 2026
- AI generated
- no
- Story unit
- 2026-06-14-rio-de-janeiro-s-city-government-shipped-a-397b-open-model-under-mit
- Labels
- source-backed, canonical briefing excerpt