CartaBlanca - a pure-Java, component-based systems simulation tool for coupled nonlinear physics on unstructured grids - an update. This paper describes a component-based nonlinear physical system simulation prototyping package written entirely in Java using object-oriented design. The package provides scientists and engineers with a developer-friendly software environment for large-scale computational algorithm and physical model development. The software design centers on the Jacobian-free Newton-Krylov solution method surrounding a finite-volume treatment of conservation equations. This enables a clean component-like implementation. We first provide motivation for the development of the software and then discuss software structure. The discussion includes a description of the use of Java’s built-in thread facility that enables parallel, shared-memory computations on a wide variety of unstructured grids with triangular, quadrilateral, tetrahedral and hexahedral elements. We also discuss the use of Java’s inheritance mechanism in the construction of a hierarchy of physics systems objects and linear and nonlinear solver objects that simplify development and foster software re-use. We provide a brief review of the Jacobian-free Newton-Krylov nonlinear system solution method and discuss how it fits into our design. Following this, we show results from example calculations and then discuss plans including the extension of the software to distributed-memory computer systems