Audience

Developers and engineering teams seeking an efficient reasoning model for long-horizon coding, software engineering, and agentic tasks

About Laguna S 2.1

Laguna S 2.1 is an open weight agentic coding model designed to pursue longer-horizon work and make effective use of reasoning. It uses a 118-billion-parameter Mixture-of-Experts architecture with 8 billion active parameters per token and supports a context window of up to one million tokens in both thinking and no-thinking modes. Its compact active size makes it suitable for complex work on local machines while remaining competitive with models many times larger on terminal, software-engineering, codebase-question-answering, and tool-use benchmarks. Laguna S 2.1 is built to keep working through difficult tasks with greater persistence, verification, and willingness to backtrack instead of declaring success too early. In demonstrated runs, it built and validated a browser rendering engine from an empty folder, optimized an agent harness for faster execution and substantially lower memory allocation, and completed extended mathematical research using the tools in its environment.

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Integrations

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Ratings/Reviews - 1 User Review

Overall 5.0 / 5
ease 5.0 / 5
features 4.0 / 5
design 5.0 / 5
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Company Information

Poolside
Founded: 2023
United States
poolside.ai/blog/introducing-laguna-s-2-1

Videos and Screen Captures

Laguna S 2.1 Screenshot 1
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Product Details

Platforms Supported
Cloud
Training
Documentation
Webinars
Support
Online

Laguna S 2.1 Frequently Asked Questions

Q: What kinds of users and organization types does Laguna S 2.1 work with?
Laguna S 2.1 works with these users and organization types: Mid Size Business, Small Business, Enterprise, Freelance, Nonprofit, Government, and Startup.
Q: What languages does Laguna S 2.1 support in their product?
Laguna S 2.1 supports these languages: English.
Q: What kind of support options does Laguna S 2.1 offer?
Laguna S 2.1 offers support via online.
Q: What other applications or services does Laguna S 2.1 integrate with?
Laguna S 2.1 integrates with: Agent Client Protocol (ACP), Claude Code, Cline, Hermes Agent, Hugging Face, IntelliJ IDEA, Kilo Code, Nous Portal, Ollama, OpenAI Codex, OpenClaw, OpenCode, OpenRouter, Poolside, Roo Code, Visual Studio Code, Visual Studio, and Zed.
Q: What type of training does Laguna S 2.1 provide?
Laguna S 2.1 provides training in the form of documentation and webinars.

Laguna S 2.1 Product Features

Laguna S 2.1 Verified User Reviews

Write a Review
  • A Laguna S 2.1 User
    Engineer
    Used the software for: Less than 6 months
    Frequency of Use: Daily
    User Role: User
    Company Size: 100 - 499
    Design 5 out of 5 stars
    Ease 5 out of 5 stars
    Features 4 out of 5 stars
    Pricing 5 out of 5 stars
    Probability You Would Recommend? 9 out of 10

    "Great long horizon model"

    5 out of 5 stars Posted 2026-07-23

    Pros: Laguna S 2.1 looks awesome from a developer’s point of view because it is built specifically for agentic coding, not just general chatbot tasks. I like that it is open-weight, relatively compact for its capability, and designed for the kind of workflows where an AI needs to inspect a repo, reason through changes, edit code, and keep moving across multiple steps.

    The 1M-token context window is a huge plus. For real engineering work, context is everything: source files, docs, logs, tests, tickets, configs, and previous attempts all matter. Having a coding model that can handle that much context makes it much more useful for serious repo-level work.

    Cons: It is still new, so I would want to test it heavily before trusting it with production code. Coding benchmarks are useful, but the real test is messy repos, weird dependencies, flaky tests, security-sensitive changes, and long-running agent loops.

    Overall: Five stars from me. Laguna S 2.1 feels like a very serious option for developers building coding agents, internal dev tools, and self-hosted AI engineering workflows. The mix of open weights, agentic coding focus, 1M-token context, and practical deployment makes it one of the most interesting coding models to watch right now.

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