# Rnj

> Essential AI's model built from scratch for code and STEM

- Category: [Foundation Models](https://ailandscape.org/category/foundation-models) › Coding Models
- Homepage: https://huggingface.co/EssentialAI
- Tags: llm, coding, open-weights
- Also known as: Rnj-1, rnj-1.5, rnj-1-instruct
- Added to the landscape: 2026-03-18

## Similar tools in Coding Models

- [CoDA](https://ailandscape.org/tool/coda): Salesforce AI Research's diffusion language model for code
- [Code World Model](https://ailandscape.org/tool/code-world-model): Meta's LLM trained to reason about how code changes program state
- [Codex](https://ailandscape.org/tool/codex): OpenAI's former -codex model line; Codex now runs on GPT-6 models
- [Cognition SWE](https://ailandscape.org/tool/cognition-swe): Cognition's in-house agentic coding models behind Devin
- [Composer](https://ailandscape.org/tool/composer): Cursor's in-house agent model, built for fast multi-step edits
- [Devstral](https://ailandscape.org/tool/devstral): Mistral AI's open-weights code agent models in 24B and 123B sizes
- [Doubao-Seed-Code](https://ailandscape.org/tool/doubao-seed-code): ByteDance's coding model on Volcengine, integrated into Trae IDE
- [Inception Mercury](https://ailandscape.org/tool/inception-mercury): Inception Labs' diffusion LLM family for fast chat, code, and edits

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Part of [AI Landscape](https://ailandscape.org), an open map of the AI ecosystem. Web page: https://ailandscape.org/tool/rnj · Index for AI assistants: https://ailandscape.org/llms.txt