Alternatives
Products that do what OpenCairn does
Open-source AI knowledge OS for notes, docs, and agents
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Hi HN, Nick here. We’re launching OpenKnowledge (https://openknowledge.ai/), a “what you see is what you get” markdown editor that has direct integrations with Claude, Codex, and other agents. Available as MacOS app or Web UI+CLI. Fully free/local and OSS. We built this because we wanted a Notion-like experience for writing and sharing markdown files across our team. Obsidian is the best alternative we tried, but found it doesn’t have a true WYSWIG UI and it didn’t integrate well with Claude/Codex outside of community plugins. So we built OpenKnowledge. It takes…
Jun 2026 · github.com
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2023 · github.com
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Hey HN! I'm Zach from Adam (https://adam.new/). We’re building an AI co-pilot for mechanical CAD software. As part of our broader research, we built a browser-based Text-to-CAD app (https://news.ycombinator.com/item?id=44182206) and are now open sourcing it. This is a React SPA with a Supabase backend. What it does: * Generates parametric 3D models from natural language descriptions, with support for both text prompts and image references * Outputs OpenSCAD code with automatically extracted parameters that surface as interactive sliders for instant dimension…
2025 · github.com
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The power of Codex with local, self-hosted models and voice
Jul 2026 · opencodesuper.app
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AI that reads your page, sees it, and gives context answers.
Dec 2025
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Hey HN, I’ve built Open Codex, a fully local, open-source alternative to OpenAI’s Codex CLI. My initial plan was to fork their project and extend it. I even started doing that. But it turned out their code has several leaky abstractions, which made it hard to override core behavior cleanly. Shortly after, OpenAI introduced breaking changes. Maintaining my customizations on top became increasingly difficult. So I rewrote the whole thing from scratch using Python. My version is designed to support local LLMs. Right now, it only works with phi-4-mini (GGUF) via…
2025 · github.com
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Hey HN! I'm open-sourcing a little weekend side project. It's a terminal UI that generates parsers for webpages using AI, and a library that runs these parsers while you browse (it connects to Chrome over CDP). You can parse Twitter, LinkedIn, and HN posts and they get saved to a DuckDB database, so you can query them later. Contributions welcome! I wrote a bit more about it here: https://0thernet.substack.com/p/memo-2-selectron
2025 · github.com
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GitHub: https://github.com/ClioAI/kw-sdk Most AI agent frameworks target code. Write code, run tests, fix errors, repeat. That works because code has a natural verification signal. It works or it doesn't. This SDK treats knowledge work like an engineering problem: Task → Brief → Rubric (hidden from executor) → Work → Verify → Fail? → Retry → Pass → Submit The orchestrator coordinates subagents, web search, code execution, and file I/O. then checks its own work against criteria it can't game (the rubric is generated in a separate call and the executor never sees it…
Feb 2026 · github.com
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