A fluid simulator that refuses results until the gates pass.CF10 specifies a VDM fluid sector built from lattice hydrodynamics, using the lattice Boltzmann method, a grid-based particle-population solver. It rewrites the update as metriplectic, meaning reversible plus dissipative dynamics, so conservation and dissipation get checked separately. The engineering deliverable is a gate suite, pass or fail checks, for stability, positivity, and entropy increase. The continuum deliverable tests whether fine grids recover incompressible Navier–Stokes, the standard fluid flow equations, via benchmark residuals. A separate section proposes a conditional regularity program, meaning no blow-ups in time, and pins the hard step to one conjecture. If small-scale tail decay, meaning activity drops fast, fails under refinement, the program stops with no loopholes. Best for: computational fluid people who want clean solver contracts and measurable continuum checks. What you can do with it: run the vortex decay viscosity test, the lid-cavity incompressibility test, and refinement collapse, then audit tail decay. What makes it trustworthy: explicit thresholds, logged artifacts, and a hard separation between proven gates and conditional hypotheses. If you only remember one thingIt treats fluid simulation like an instrument: pass the gates first, then interpret outcomes.