{"slug": "rapier", "name": "Rapier", "category": "dev-libs", "category_name": "Libraries and frameworks", "description": "", "recommenders": 3, "commenters": 7, "warners": 0, "score": 3.702, "rising": 0.35, "first": "2025-12-05", "latest": "2026-10-23", "why": "maybe the most impressive real time soft body simulation", "why_is_quote": true, "has_verdict": false, "sentiment": {"recommend": 3, "neutral": 3, "compare": 1, "warn": 0}, "spark": [0, 1, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0], "listed": true, "loved": [], "caveat": "", "short_quote": "maybe the most impressive real time soft body simulation", "kind": "", "icon": true, "domain": "rapier.rs", "github_repo": null, "official_url": "https://rapier.rs/", "pricing": "", "aliases": ["Rapier"], "verdict": null, "praise": [{"label": "", "summary": "", "quotes": [{"id": 797773776, "item_id": 49860861, "url": "https://news.ycombinator.com/item?id=49860861", "by": "jackling", "date": "2026-09-26", "version": null, "stance": "recommend", "quote": "maybe the most impressive real time soft body simulation", "excerpt": "It genuinely breaks my brain how productive S\u00e9bastien is. Does he research and build these solutions by himself? Bevy has an extremely impressive voxel collision system, and now from what I can gather, maybe the most impressive real time soft body simulation. It really distinguishes itself as simulator, not just being a N+1 sim, but genuinely ground breaking in a lot of aspects. Amazing work! I wish I was as talented", "context": "", "use_case": "physics simulation", "switched_from": "", "story": "Advanced soft-bodies for games with the Rapier physics engine"}, {"id": 779971890, "item_id": 48748243, "url": "https://news.ycombinator.com/item?id=48748243", "by": "tancop", "date": "2026-07-01", "version": null, "stance": "recommend", "quote": "i love that we went from bullet being the only real option for open source 3D physics to jolt, rapier, avian, nvidia physx and now box3d.", "excerpt": "i love that we went from bullet being the only real option for open source 3D physics to jolt, rapier, avian, nvidia physx and now box3d.", "context": "", "use_case": "3D physics engine", "switched_from": "", "story": "Announcing Box3D :: Box2D"}, {"id": 738601681, "item_id": 46162605, "url": "https://news.ycombinator.com/item?id=46162605", "by": "Fantastimaker", "date": "2025-12-05", "version": null, "stance": "recommend", "quote": "Rapier for fast physics", "excerpt": "Just released the first update to my gridless spaceship building game \"eXoSpace Combat Engineer\". No engine used, built using pure Rust with: - Rapier for fast physics - WGPU for cross-platform rendering - EGUI for the GUI Although building a game without an engine usually is considered inefficient, my experience - as an experienced software engineer - is that it is quite doable with this stack. Steam: https://store.", "context": "", "use_case": "Physics engine", "switched_from": "", "story": "eXoSpace \u2013 Built Using Rust, Rapier, WGPU and EGUI"}]}], "caveats": [], "who": [], "tags": [], "use_cases": ["physics simulation", "physics engine", "3d physics engine", "physics for browser chess game", "browser physics"], "compared": [{"slug": "three-js", "name": "Three.js", "co": 2, "switched_from": 0, "switched_to": 0}, {"slug": "box3d", "name": "Box3D", "co": 2, "switched_from": 0, "switched_to": 0}], "makers": [], "threads": [{"url": "https://news.ycombinator.com/item?id=50202746", "title": "Show HN: Impossible Machines: declaratively program the physical world", "mentions": 2}, {"url": "https://news.ycombinator.com/item?id=48745445", "title": "Announcing Box3D :: Box2D", "mentions": 2}, {"url": "https://news.ycombinator.com/item?id=49844430", "title": "Advanced soft-bodies for games with the Rapier physics engine", "mentions": 1}, {"url": "https://news.ycombinator.com/item?id=46784221", "title": "Show HN: Mystral Native \u2013 Run JavaScript games natively with WebGPU (no browser)", "mentions": 1}, {"url": "https://news.ycombinator.com/item?id=46662001", "title": "A Year of 3D Printing", "mentions": 1}, {"url": "https://news.ycombinator.com/item?id=46162604", "title": "eXoSpace \u2013 Built Using Rust, Rapier, WGPU and EGUI", "mentions": 1}], "sentiment_by_month": {"2025-11": {}, "2025-12": {"recommend": 1}, "2026-01": {"neutral": 2}, "2026-02": {}, "2026-03": {}, "2026-04": {}, "2026-05": {}, "2026-06": {}, "2026-07": {"recommend": 1, "compare": 1}, "2026-08": {}, "2026-09": {"recommend": 1}, "2026-10": {"neutral": 1}}, "versions": [], "version_unnamed": 0, "family_ref": null, "runs_on": null, "lines": [], "quotes": [{"id": 803443714, "item_id": 50215232, "url": "https://news.ycombinator.com/item?id=50215232", "by": "bhaprayan", "date": "2026-10-23", "version": null, "stance": "neutral", "quote": "Rapier (https://rapier.rs/) for simulating bodies, joints, collisions, forces, etc.", "excerpt": "Happy to open source, the code is a little messy right now, so I\u2019ll clean it up and post a link in a few days! High level: I\u2019m using ThreeJS for the rendering and Rapier (https://rapier.rs/) for simulating bodies, joints, collisions, forces, etc. The mechanism is solved for using a simple heuristic search (eg constraints, etc that you introduce in the scene) and then run through Rapier to find a configuration that wo", "context": "", "use_case": "physics simulation", "switched_from": "", "story": "Show HN: Impossible Machines: declaratively program the physical world"}, {"id": 803421200, "item_id": 50213825, "url": "https://news.ycombinator.com/item?id=50213825", "by": "bhaprayan", "date": "2026-10-23", "version": null, "stance": "neutral", "quote": "I'm running a simple heuristic to test for candidate solutions and running them through Rapier (https://rapier.rs)", "excerpt": "That was cool! Watched the demo video, didn't go through the paper yet. I'm running a simple heuristic to test for candidate solutions and running them through Rapier (https://rapier.rs), but simulated annealing to efficiently search the configuration space would be a nice extension.", "context": "", "use_case": "Physics simulation", "switched_from": "", "story": "Show HN: Impossible Machines: declaratively program the physical world"}, {"id": 797773776, "item_id": 49860861, "url": "https://news.ycombinator.com/item?id=49860861", "by": "jackling", "date": "2026-09-26", "version": null, "stance": "recommend", "quote": "maybe the most impressive real time soft body simulation", "excerpt": "It genuinely breaks my brain how productive S\u00e9bastien is. Does he research and build these solutions by himself? Bevy has an extremely impressive voxel collision system, and now from what I can gather, maybe the most impressive real time soft body simulation. It really distinguishes itself as simulator, not just being a N+1 sim, but genuinely ground breaking in a lot of aspects. Amazing work! I wish I was as talented", "context": "", "use_case": "physics simulation", "switched_from": "", "story": "Advanced soft-bodies for games with the Rapier physics engine"}, {"id": 779987056, "item_id": 48749191, "url": "https://news.ycombinator.com/item?id=48749191", "by": "utopiah", "date": "2026-07-01", "version": null, "stance": "compare", "quote": "I'm a bit familiar with Rapier (and before that Cannon and Ammo) so how does it compare?", "excerpt": "I'm a bit familiar with Rapier (and before that Cannon and Ammo) so how does it compare? PS: FWIW made my own physics engine in 3D space just few weeks ago (and shared it here). OK ok ... it's just a 1-liner that brings an object down at regular interval but it's surprising how well it works already! I recommend you give it a go as from a learning perspective it's really fun.", "context": "", "use_case": "physics engine", "switched_from": "", "story": "Announcing Box3D :: Box2D"}, {"id": 779971890, "item_id": 48748243, "url": "https://news.ycombinator.com/item?id=48748243", "by": "tancop", "date": "2026-07-01", "version": null, "stance": "recommend", "quote": "i love that we went from bullet being the only real option for open source 3D physics to jolt, rapier, avian, nvidia physx and now box3d.", "excerpt": "i love that we went from bullet being the only real option for open source 3D physics to jolt, rapier, avian, nvidia physx and now box3d.", "context": "", "use_case": "3D physics engine", "switched_from": "", "story": "Announcing Box3D :: Box2D"}, {"id": 749417473, "item_id": 46838592, "url": "https://news.ycombinator.com/item?id=46838592", "by": "danjl", "date": "2026-01-31", "version": null, "stance": "neutral", "quote": "It does use the rapier physics library", "excerpt": "Here's a dawn implementation with support for ray tracing that was implemented a number of years ago but never integrated into browsers. Perhaps it will help? https://github.com/maierfelix/dawn-ray-tracing Yes, chessboard3d.app is written with raw JS APIs and raw WebGPU. It does use the rapier physics library, which uses WASM, which might be an issue? It implements its own ray tracing but would probably run 10x faste", "context": "", "use_case": "Physics for browser chess game", "switched_from": "", "story": "Show HN: Mystral Native \u2013 Run JavaScript games natively with WebGPU (no browser)"}, {"id": 747529969, "item_id": 46720623, "url": "https://news.ycombinator.com/item?id=46720623", "by": "brookke", "date": "2026-01-22", "version": null, "stance": "neutral", "quote": "It's using three.js with rapier for physics.", "excerpt": "Hey! It's using three.js with rapier for physics. The models are being loaded as STLs using the three.js stl loader https://threejs.org/docs/#STLLoader. https://github.com/Brookke/brookke.github.io/blob/main/src/components/STLPileViewer.tsx", "context": "", "use_case": "Browser physics", "switched_from": "", "story": "A Year of 3D Printing"}, {"id": 738601681, "item_id": 46162605, "url": "https://news.ycombinator.com/item?id=46162605", "by": "Fantastimaker", "date": "2025-12-05", "version": null, "stance": "recommend", "quote": "Rapier for fast physics", "excerpt": "Just released the first update to my gridless spaceship building game \"eXoSpace Combat Engineer\". No engine used, built using pure Rust with: - Rapier for fast physics - WGPU for cross-platform rendering - EGUI for the GUI Although building a game without an engine usually is considered inefficient, my experience - as an experienced software engineer - is that it is quite doable with this stack. Steam: https://store.", "context": "", "use_case": "Physics engine", "switched_from": "", "story": "eXoSpace \u2013 Built Using Rust, Rapier, WGPU and EGUI"}]}