{"slug": "show-hn-lacuna-open-source-inline-ai-writing-suggestions-for-your-mac", "title": "Show HN: Lacuna – open-source inline AI writing suggestions for your Mac", "summary": "Developer Jack Damon released Lacuna, an open-source Mac tool that sends a bracketed phrase plus surrounding text to a user-configured LLM and returns 3 candidate replacement phrases, triggered by Shift-Command-K. The tool is keyboard navigable, inspired by the open-source window-tiling utility Rectangle, and is available on GitHub; Damon said he uses it most often for drafting emails.", "body_md": "This past week I built (prompted) a tool I find myself using day to day and wanted to share it with others who may find it useful as well.\n\n“Lacuna” is an opinionated way to invoke LLMs into any text input on your Mac. Specifically, you can type bracketed phrases {such as this}, press Shift-Command-K (or a different shortcut of your choosing), and the tool sends your bracketed phrase + the surrounding text contents to an LLM of your configuration for generating text to replace the bracketed phrase. The program returns 3 candidate phrases and the experience is entirely keyboard navigable.\n\nDemo: [https://jackdamon.org/assets/images/lacuna-scheduling-demo.g...](https://jackdamon.org/assets/images/lacuna-scheduling-demo.gif)\n\nExample scheduling workflow using Lacuna’s native UI and sample suggestions.\n\nSo far I find myself frequently using it when drafting emails where I want help with quick phrasing.\n\nThe project was inspired by Rectangle, an open source utility app for window tiling that is keyboard based.\n\nLacuna is open source and available here: [https://github.com/jdamon96/lacuna](https://github.com/jdamon96/lacuna)\n\nBlog: [https://jackdamon.org/blog/lacuna/](https://jackdamon.org/blog/lacuna/)\n\nComments URL: [https://news.ycombinator.com/item?id=50025559](https://news.ycombinator.com/item?id=50025559)\n\nPoints: 1\n\n# Comments: 0", "url": "https://wpnews.pro/news/show-hn-lacuna-open-source-inline-ai-writing-suggestions-for-your-mac", "canonical_source": "https://jackdamon.org/blog/lacuna/", "published_at": "2026-10-09 19:31:15+00:00", "updated_at": "2026-10-09 19:52:28.816351+00:00", "lang": "en", "topics": ["ai-tools", "generative-ai", "developer-tools", "ai-products"], "entities": ["Lacuna", "Jack Damon", "Rectangle", "GitHub", "Mac"], "also_reported_by": [], "alternates": {"html": "https://wpnews.pro/news/show-hn-lacuna-open-source-inline-ai-writing-suggestions-for-your-mac", "markdown": "https://wpnews.pro/news/show-hn-lacuna-open-source-inline-ai-writing-suggestions-for-your-mac.md", "text": "https://wpnews.pro/news/show-hn-lacuna-open-source-inline-ai-writing-suggestions-for-your-mac.txt", "jsonld": "https://wpnews.pro/news/show-hn-lacuna-open-source-inline-ai-writing-suggestions-for-your-mac.jsonld"}}