← The Wire

Public story · 2026-02-20 · source-backed

stepfun-ai/Step-3.5-Flash — Open-Source 196B MoE (1.4K stars)

Confidence
source-backed
Sources
1
Redaction
redacted

Story

GitHub | 196B total / 11B active, Apache 2.0

StepFun's sparse MoE activates only 11B of 196B parameters per token, delivering 74.4% SWE-bench, 97.3% AIME 2025, and 100-300 tok/s throughput. Supports INT4 GGUF for local inference. Apache 2.0 licensed. One of the most capable fully open-source agentic models available. Trending on HN with 224 points.

Related stories

Each link below shares sources, entities, or timing with this story.

  1. Shared entities / Same source domain / Shared topic / What happened next

    Alibaba open-sources Qwen-AgentWorld, a flight simulator for your agents

    Both cover Apache, GitHub, MoE, SWE; reported by the same outlet (github.com); overlapping topics (apache, model).

  2. Shared entities / Shared topic / What happened next / Tension

    Microsoft's MAI coding models reach Copilot and VS Code.

    Both cover AIME, Flash, MoE, SWE; overlapping topics (aime, model); picks up the AIME thread on 2026-06-07.

  3. Shared entities / Same source domain / Shared topic / What happened next

    Gemma 4 Ships Under Apache 2.0 and the Numbers Are Absurd

    Both cover AIME, Apache, MoE; reported by the same outlet (github.com); overlapping topics (apache, inference, model).

  4. Shared entities / Shared topic / What happened next

    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 Apache, Flash, MoE, SWE; overlapping topics (apache, inference); picks up the Apache thread on 2026-04-24.

  5. Shared entities / Same source domain / Shared topic / What happened next

    Devstral 2 is open source, 123B params, hits 72.2% SWE-bench, and costs a seventh of Sonnet

    Both cover Apache, GitHub, SWE; reported by the same outlet (github.com); overlapping topics (apache, model).

  6. Shared entities / Shared topic / What happened next

    Poolside Ships a 68.2% SWE-bench Coding Agent That Runs on Your Mac. Apache 2.0.

    Both cover Apache, MoE, SWE; overlapping topics (active, apache, local, model); picks up the Apache thread on 2026-04-29.

  7. Shared entities / Shared topic / What happened next / Tension

    Run Claude Code Against GLM-5 (744B) for Free via NIM Proxy

    Both cover AIME, MoE, SWE; overlapping topics (active, aime); picks up the AIME thread on 2026-03-10.

  8. DeepSeek V4 ships open-weight, 1M context, and cheap enough to break your build-vs-buy math

    Both cover Flash, SWE; overlapping topics (active, agentic, flash, model); picks up the Flash thread on 2026-06-15.

Source trail

Entities

Provenance

AI generated
no
Story unit
2026-02-20-stepfun-ai-step-3-5-flash-open-source-196b-moe-1-4k-stars
Labels
source-backed, canonical briefing excerpt