Molt: A Lightweight RL Training Framework
heghbalz · x · 2026-07-14
A reshared post introducing a new RL training framework named Molt, designed to replace the increasingly bloated Megatron stack, making it easier for researchers to modify and experiment.
Key highlights include:
- Built on PyTorch-native + vLLM with a streamlined interface
- Supports fully async, R3, TP/EP/CP, TITO, and multimodal training
- Tailored for MoE RL training, scaling up to 1T parameters
- The codebase is roughly 8,000 lines, about 1/3 the size of Slime and 1/9 of Verl
The author's stance is clear: this is a much lighter alternative that you can start hacking on right away.
Related event: NVIDIA Introduces Molt: A Pure PyTorch RL Framework(3 posts)→
More from Companies & People
- Anthropic Insiders: Not Everyone at the Lab Believes in High p(doom) — anpaure · 2026-09-11
- Lumara AI Film Festival Comes to NYC Oct 26, Top AI Filmmakers to Compete — 0xAllen_ · 2026-09-11
- X drama: Anthropic researchers accused of spying on academic customers and racing them to results — basedjensen · 2026-09-11
- Investor argues Palantir-Nvidia partnership should slash Anthropic's IPO valuation — pdamodaran · 2026-09-11
- a16z podcast: why 2-3 person startups are absent from policy debates — a16z Podcast · 2026-09-11
- PyTorch Day Korea 2026 launches first offline conf, CFP closes Sept 13 — PyTorch · 2026-09-11