A computational framework for modeling and simulating fast dynamic fluid–structure interaction is presented. The approach relies on a partitioned coupling strategy that preserves the fundamental properties of hyperbolic systems, namely local conservation (mass, momentum, and energy) and invariant-domain preservation. Both the Euler equations for the fluid and the hyperelastic equations for the solid are reformulated in an updated-Lagrangian frame, enabling the use of robust and well-established schemes for each subsystem [1, 5, 4, 3]. The coupling at the fluid–solid interface is formulated as a constrained minimization problem, ensuring consistency, local conservation, and stability. We then show how the design choices of our partitioned framework make the construction of second-order extensions, local time-stepping strategies [2], and sliding algorithms both natural and efficient. Finally, we discuss the extension of the methodology to elastoplastic materials, using a von Mises criterion together with either a relaxation strategy or a radial projection method. References [1] Gilles Carré, Stéphane Del Pino, Bruno Després, and Emmanuel Labourasse. A cell-centered lagrangian hydrodynamics scheme on general unstructured meshes in arbitrary dimension. Journal of Computational Physics, 228(14):5160–5183, 2009. [2] Teddy Chantrait, Nicolas Chevaugeon, Stéphane Del Pino, Alexandre Gangloff, and Emmanuel Labourasse. Subcycling strategy for finite-volume updated-lagrangian methods applied to fluid–structure interaction. International Journal for Numerical Methods in Engineering, 126(11):e70051, 2025. [3] Gabriel Georges, Jérôme Breil, and Pierre-Henri Maire. A 3d gcl compatible cell-centered lagrangian scheme for solving gas dynamics equations. Journal of Computational Physics, 305:921–941, 2016. [4] Gilles Kluth and Bruno Després. Discretization of hyperelasticity on unstructured mesh with a cell-centered lagrangian scheme. Journal of Computational Physics, 229(24):9092–9118, 2010. [5] Maire Pierre-Henri, Remi Abgrall, Jérôme Breil, Raphaël Loubère, and Bernard Rebourcet. A nominally second-order cell-centered lagrangian scheme for simulating elastic-plastic flows on two-dimensional unstructured grids. Rapport de recherche RR-7975, INRIA, 2012.