Mellum2 is an AI Code tool. Fast Mixture-of-Experts model for software engineering workflows and AI agent systems. Key features include Mixture-of-Experts Architecture, Private Local Deployment, and AI Workflow Routing. Best for software developers and engineers and data scientists and analysts.
About Mellum2
Mellum2 is a 12B-parameter open-source language model built by JetBrains for software engineering tasks. It uses Mixture-of-Experts architecture with only 2.5B active parameters per token, making it twice as fast as similar models for code generation, routing, RAG pipelines, and sub-agent workflows.
Key Features
Mixture-of-Experts Architecture.
Private Local Deployment.
AI Workflow Routing.
Fast RAG Pipelines.
Sub-Agent Task Handling.
Multiple Model Variants.
Frequently Asked Questions
Mellum2 is an open-source 12B-parameter language model from JetBrains designed for software engineering workflows. It uses Mixture-of-Experts architecture to activate only 2.5B parameters per token, making it fast and cost-efficient for code generation, routing, RAG pipelines, and AI agent systems.
Yes, Mellum2 is released under the Apache 2.0 license, which means it's free to use, modify, and deploy. You can run it locally, self-host it, or fine-tune it for your own applications without licensing restrictions.
Mellum2 is built as a focal model for high-frequency tasks in AI systems rather than trying to compete with frontier models. It's twice as fast as similar-sized models and specializes in natural language and code without multimodal features, keeping it lean and efficient for software engineering environments.
Mellum2 is ideal for software developers and engineering teams building AI systems that need fast, private, and cost-efficient code assistance. It works well for IDE integrations, agent workflows, RAG pipelines, and organizations that want to deploy AI on their own infrastructure without sending code to external services.
