Cumulus Labs

ActiveAI-native

The Fastest Multimodal Inference OS

What it does

Cumulus Labs lets engineering teams ship AI in production without needing a dedicated ML platform team. Right now, companies building AI products are forced to stitch together separate vendors for routing, observability, evaluation, fine-tuning, and inference. This fragmented approach is brittle, expensive, and is a common reason enterprises fail with AI. We replace that entire stack with a single unified platform. Developers can keep their existing code while instantly upgrading to a unified platform that handles routing, semantic caching, continuous shadow evaluation, simulated data, and one-click fine-tuning. Behind the platform is Ion, our proprietary inference engine running on a custom NVIDIA Grace GPU fleet. Ion uses in-house custom GPU kernels to deliver 30 to 50 percent more throughput than standard vLLM or SGLang, giving our customers SOTA inference economics.

Its site says now · captured 2026-08-23

Cumulus Labs — Production-Grade Inference. Routed, Evaluated, Fine-Tuned.

Cumulus is the unified inference platform for production AI. OpenAI-compatible gateway, per-workflow routing, prompt and KV cache, real-time observability, continuous evaluation, one-click LoRA fine-tuning, and the Ion inference engine — 30 to 50% more throughput than vLLM and SGLang on NVIDIA Grace and Blackwell.

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