{"slug": "manifold", "name": "Manifold", "category": "dev-libs", "category_name": "Libraries and frameworks", "description": "Open-source C++ library for fast, robust 3D mesh boolean (CSG) operations.", "recommenders": 5, "commenters": 5, "warners": 0, "score": 4.528, "rising": -0.31, "first": "2025-12-20", "latest": "2026-10-11", "why": "Liked as the fast new geometry backend in OpenSCAD, far quicker than the old CGAL renderer, and as a CSG meshing library integrated into Godot and Blender.", "why_is_quote": false, "has_verdict": true, "sentiment": {"recommend": 5, "neutral": 0, "compare": 0, "warn": 0}, "spark": [0, 1, 0, 0, 1, 0, 0, 1, 1, 0, 0, 1], "listed": true, "loved": ["Speed", "Engine integration"], "caveat": "", "short_quote": "If you want reification/meshing I recommend [1] which is what Godot uses.", "icon": true, "domain": null, "github_repo": "github.com/elalish/manifold", "official_url": "https://manifoldcad.org", "pricing": "open source", "aliases": ["Manifold", "manifold"], "verdict": [{"text": "Liked as the fast new geometry backend in OpenSCAD, far quicker than the old CGAL renderer,", "cites": [{"id": 800623697, "item_id": 50038981, "url": "https://news.ycombinator.com/item?id=50038981", "by": "nayuki", "date": "2026-10-11", "stance": "recommend", "quote": "The Manifold renderer is so much faster than the old CGAL", "excerpt": "I use OpenSCAD as my primary design tool for 3D modeling. I get things done, but it isn't easy, and it's hard to recommend it to other people. OpenSCAD really requires the user to mathematics, trigonometry, mental visualization, and programming beforehand as prerequisites - unlike mainstream CAD programs which are more point-and-click friendly. Performing fillets and chamfers on corners is quite tedious, and describi", "context": "", "use_case": "OpenSCAD rendering", "switched_from": "CGAL", "story": "OpenSCAD the Programmers Solid 3D CAD Modeller"}, {"id": 741425792, "item_id": 46339112, "url": "https://news.ycombinator.com/item?id=46339112", "by": "coryrc", "date": "2025-12-20", "stance": "recommend", "quote": "Trivial operations are two orders of magnitude faster and complex ones every faster.", "excerpt": "It's switched to a new backend https://github.com/elalish/manifold Which you can also use directly instead by writing C++. Trivial operations are two orders of magnitude faster and complex ones every faster.", "context": "", "use_case": "CAD geometry kernel", "switched_from": "", "story": "OpenSCAD is kinda neat"}]}, {"text": " and as a CSG meshing library integrated into Godot and Blender.", "cites": [{"id": 785337776, "item_id": 49083611, "url": "https://news.ycombinator.com/item?id=49083611", "by": "iFire", "date": "2026-07-28", "stance": "recommend", "quote": "I spent a lot of time making elalish/manifold work in Godot Engine and it is now a method in Blender too.", "excerpt": "How does it compare against https://github.com/elalish/manifold in performance and zero corruption? I spent a lot of time making elalish/manifold work in Godot Engine and it is now a method in Blender too. https://manifoldcad.org If it helps, feel free to use the apache2 licensed unit tests that were generated in manifold development https://github.com/elalish/manifold/tree/master/test", "context": "integrated Manifold into Godot Engine", "use_case": "3D CSG geometry", "switched_from": "", "story": "Show HN: Formally verified 3D CSG: Trust 93 lines spec, not 1000 lines AI code"}, {"id": 775409424, "item_id": 48463089, "url": "https://news.ycombinator.com/item?id=48463089", "by": "avaer", "date": "2026-06-09", "stance": "recommend", "quote": "If you want reification/meshing I recommend [1] which is what Godot uses.", "excerpt": "Text to CAD doesn't need papers. You can literally just try it and see that it works well with the frontier models. If you want reification/meshing I recommend [1] which is what Godot uses. You can throw the results in a physics engine in an afternoon and see for yourself. This wasn't obvious a year ago, but today CAD literally reduces to Simon Wilson's pelican test, since CAD is largely a matter of functional CSG, a", "context": "", "use_case": "CSG meshing", "switched_from": "", "story": "Unified Controllable and Faithful Text-to-CAD Generation with LLMs"}]}, {"text": " No complaints are mentioned; it suits OpenSCAD users and developers who need CSG in C++ or game engines.", "cites": [{"id": 800623697, "item_id": 50038981, "url": "https://news.ycombinator.com/item?id=50038981", "by": "nayuki", "date": "2026-10-11", "stance": "recommend", "quote": "The Manifold renderer is so much faster than the old CGAL", "excerpt": "I use OpenSCAD as my primary design tool for 3D modeling. I get things done, but it isn't easy, and it's hard to recommend it to other people. OpenSCAD really requires the user to mathematics, trigonometry, mental visualization, and programming beforehand as prerequisites - unlike mainstream CAD programs which are more point-and-click friendly. Performing fillets and chamfers on corners is quite tedious, and describi", "context": "", "use_case": "OpenSCAD rendering", "switched_from": "CGAL", "story": "OpenSCAD the Programmers Solid 3D CAD Modeller"}, {"id": 741425792, "item_id": 46339112, "url": "https://news.ycombinator.com/item?id=46339112", "by": "coryrc", "date": "2025-12-20", "stance": "recommend", "quote": "Trivial operations are two orders of magnitude faster and complex ones every faster.", "excerpt": "It's switched to a new backend https://github.com/elalish/manifold Which you can also use directly instead by writing C++. Trivial operations are two orders of magnitude faster and complex ones every faster.", "context": "", "use_case": "CAD geometry kernel", "switched_from": "", "story": "OpenSCAD is kinda neat"}, {"id": 775409424, "item_id": 48463089, "url": "https://news.ycombinator.com/item?id=48463089", "by": "avaer", "date": "2026-06-09", "stance": "recommend", "quote": "If you want reification/meshing I recommend [1] which is what Godot uses.", "excerpt": "Text to CAD doesn't need papers. You can literally just try it and see that it works well with the frontier models. If you want reification/meshing I recommend [1] which is what Godot uses. You can throw the results in a physics engine in an afternoon and see for yourself. This wasn't obvious a year ago, but today CAD literally reduces to Simon Wilson's pelican test, since CAD is largely a matter of functional CSG, a", "context": "", "use_case": "CSG meshing", "switched_from": "", "story": "Unified Controllable and Faithful Text-to-CAD Generation with LLMs"}]}], "praise": [{"label": "Speed", "summary": "Much faster than CGAL, with trivial operations reported two orders of magnitude faster.", "quotes": [{"id": 800623697, "item_id": 50038981, "url": "https://news.ycombinator.com/item?id=50038981", "by": "nayuki", "date": "2026-10-11", "stance": "recommend", "quote": "The Manifold renderer is so much faster than the old CGAL", "excerpt": "I use OpenSCAD as my primary design tool for 3D modeling. I get things done, but it isn't easy, and it's hard to recommend it to other people. OpenSCAD really requires the user to mathematics, trigonometry, mental visualization, and programming beforehand as prerequisites - unlike mainstream CAD programs which are more point-and-click friendly. Performing fillets and chamfers on corners is quite tedious, and describi", "context": "", "use_case": "OpenSCAD rendering", "switched_from": "CGAL", "story": "OpenSCAD the Programmers Solid 3D CAD Modeller"}, {"id": 741425792, "item_id": 46339112, "url": "https://news.ycombinator.com/item?id=46339112", "by": "coryrc", "date": "2025-12-20", "stance": "recommend", "quote": "Trivial operations are two orders of magnitude faster and complex ones every faster.", "excerpt": "It's switched to a new backend https://github.com/elalish/manifold Which you can also use directly instead by writing C++. Trivial operations are two orders of magnitude faster and complex ones every faster.", "context": "", "use_case": "CAD geometry kernel", "switched_from": "", "story": "OpenSCAD is kinda neat"}]}, {"label": "Engine integration", "summary": "Used in Godot Engine and available as a method in Blender.", "quotes": [{"id": 785337776, "item_id": 49083611, "url": "https://news.ycombinator.com/item?id=49083611", "by": "iFire", "date": "2026-07-28", "stance": "recommend", "quote": "I spent a lot of time making elalish/manifold work in Godot Engine and it is now a method in Blender too.", "excerpt": "How does it compare against https://github.com/elalish/manifold in performance and zero corruption? I spent a lot of time making elalish/manifold work in Godot Engine and it is now a method in Blender too. https://manifoldcad.org If it helps, feel free to use the apache2 licensed unit tests that were generated in manifold development https://github.com/elalish/manifold/tree/master/test", "context": "integrated Manifold into Godot Engine", "use_case": "3D CSG geometry", "switched_from": "", "story": "Show HN: Formally verified 3D CSG: Trust 93 lines spec, not 1000 lines AI code"}, {"id": 775409424, "item_id": 48463089, "url": "https://news.ycombinator.com/item?id=48463089", "by": "avaer", "date": "2026-06-09", "stance": "recommend", "quote": "If you want reification/meshing I recommend [1] which is what Godot uses.", "excerpt": "Text to CAD doesn't need papers. You can literally just try it and see that it works well with the frontier models. If you want reification/meshing I recommend [1] which is what Godot uses. You can throw the results in a physics engine in an afternoon and see for yourself. This wasn't obvious a year ago, but today CAD literally reduces to Simon Wilson's pelican test, since CAD is largely a matter of functional CSG, a", "context": "", "use_case": "CSG meshing", "switched_from": "", "story": "Unified Controllable and Faithful Text-to-CAD Generation with LLMs"}]}, {"label": "CSG meshing", "summary": "Recommended for reification and meshing of CSG models.", "quotes": [{"id": 775409424, "item_id": 48463089, "url": "https://news.ycombinator.com/item?id=48463089", "by": "avaer", "date": "2026-06-09", "stance": "recommend", "quote": "If you want reification/meshing I recommend [1] which is what Godot uses.", "excerpt": "Text to CAD doesn't need papers. You can literally just try it and see that it works well with the frontier models. If you want reification/meshing I recommend [1] which is what Godot uses. You can throw the results in a physics engine in an afternoon and see for yourself. This wasn't obvious a year ago, but today CAD literally reduces to Simon Wilson's pelican test, since CAD is largely a matter of functional CSG, a", "context": "", "use_case": "CSG meshing", "switched_from": "", "story": "Unified Controllable and Faithful Text-to-CAD Generation with LLMs"}]}], "caveats": [], "who": [{"by": "iFire", "context": "integrated Manifold into Godot Engine", "url": "https://news.ycombinator.com/item?id=49083611", "date": "2026-07-28"}], "tags": ["for OpenSCAD users", "for C++ developers", "for game engines"], "use_cases": ["openscad rendering", "3d csg geometry", "csg meshing", "delegation in java", "cad geometry kernel"], "compared": [], "makers": [], "threads": [{"url": "https://news.ycombinator.com/item?id=49984349", "title": "OpenSCAD the Programmers Solid 3D CAD Modeller", "mentions": 1}, {"url": "https://news.ycombinator.com/item?id=49083239", "title": "Show HN: Formally verified 3D CSG: Trust 93 lines spec, not 1000 lines AI code", "mentions": 1}, {"url": "https://news.ycombinator.com/item?id=48461311", "title": "Unified Controllable and Faithful Text-to-CAD Generation with LLMs", "mentions": 1}, {"url": "https://news.ycombinator.com/item?id=47416548", "title": "Java 26 is here, and with it a solid foundation for the future", "mentions": 1}, {"url": "https://news.ycombinator.com/item?id=46337984", "title": "OpenSCAD is kinda neat", "mentions": 1}], "sentiment_by_month": {"2025-11": {}, "2025-12": {"recommend": 1}, "2026-01": {}, "2026-02": {}, "2026-03": {"recommend": 1}, "2026-04": {}, "2026-05": {}, "2026-06": {"recommend": 1}, "2026-07": {"recommend": 1}, "2026-08": {}, "2026-09": {}, "2026-10": {"recommend": 1}}, "quotes": [{"id": 800623697, "item_id": 50038981, "url": "https://news.ycombinator.com/item?id=50038981", "by": "nayuki", "date": "2026-10-11", "stance": "recommend", "quote": "The Manifold renderer is so much faster than the old CGAL", "excerpt": "I use OpenSCAD as my primary design tool for 3D modeling. I get things done, but it isn't easy, and it's hard to recommend it to other people. OpenSCAD really requires the user to mathematics, trigonometry, mental visualization, and programming beforehand as prerequisites - unlike mainstream CAD programs which are more point-and-click friendly. Performing fillets and chamfers on corners is quite tedious, and describi", "context": "", "use_case": "OpenSCAD rendering", "switched_from": "CGAL", "story": "OpenSCAD the Programmers Solid 3D CAD Modeller"}, {"id": 785337776, "item_id": 49083611, "url": "https://news.ycombinator.com/item?id=49083611", "by": "iFire", "date": "2026-07-28", "stance": "recommend", "quote": "I spent a lot of time making elalish/manifold work in Godot Engine and it is now a method in Blender too.", "excerpt": "How does it compare against https://github.com/elalish/manifold in performance and zero corruption? I spent a lot of time making elalish/manifold work in Godot Engine and it is now a method in Blender too. https://manifoldcad.org If it helps, feel free to use the apache2 licensed unit tests that were generated in manifold development https://github.com/elalish/manifold/tree/master/test", "context": "integrated Manifold into Godot Engine", "use_case": "3D CSG geometry", "switched_from": "", "story": "Show HN: Formally verified 3D CSG: Trust 93 lines spec, not 1000 lines AI code"}, {"id": 775409424, "item_id": 48463089, "url": "https://news.ycombinator.com/item?id=48463089", "by": "avaer", "date": "2026-06-09", "stance": "recommend", "quote": "If you want reification/meshing I recommend [1] which is what Godot uses.", "excerpt": "Text to CAD doesn't need papers. You can literally just try it and see that it works well with the frontier models. If you want reification/meshing I recommend [1] which is what Godot uses. You can throw the results in a physics engine in an afternoon and see for yourself. This wasn't obvious a year ago, but today CAD literally reduces to Simon Wilson's pelican test, since CAD is largely a matter of functional CSG, a", "context": "", "use_case": "CSG meshing", "switched_from": "", "story": "Unified Controllable and Faithful Text-to-CAD Generation with LLMs"}, {"id": 758886608, "item_id": 47430413, "url": "https://news.ycombinator.com/item?id=47430413", "by": "owlstuffing", "date": "2026-03-18", "stance": "recommend", "quote": "The manifold project provides true delegation[1] for Java.", "excerpt": "Kotlin's \"delegation\" feature isn't true delegation, it's just call forwarding, which is better than nothing, but it falls down pretty quickly as an alternative to implementation inheritance. The manifold project provides true delegation[1] for Java. 1. https://github.com/manifold-systems/manifold/blob/master/manifold-deps-parent/manifold-delegation/README.md", "context": "", "use_case": "delegation in Java", "switched_from": "", "story": "Java 26 is here, and with it a solid foundation for the future"}, {"id": 741425792, "item_id": 46339112, "url": "https://news.ycombinator.com/item?id=46339112", "by": "coryrc", "date": "2025-12-20", "stance": "recommend", "quote": "Trivial operations are two orders of magnitude faster and complex ones every faster.", "excerpt": "It's switched to a new backend https://github.com/elalish/manifold Which you can also use directly instead by writing C++. Trivial operations are two orders of magnitude faster and complex ones every faster.", "context": "", "use_case": "CAD geometry kernel", "switched_from": "", "story": "OpenSCAD is kinda neat"}]}