LSDx is a quantitative risk and pricing layer for liquid staking derivatives. It separates liquidity, yield, and valuation, then reconnects them through explicit underwriting. The framework measures path-dependent risks—peg instability, exit queues, validator penalties, and rehypothecation chains—and converts them into capital charges. It delivers regime-aware ratings, fair-yield curves, and sizing limits for allocators. Models combine Bayesian updating with robust optimisation and stress tests under liquidity and validator shocks. Data inputs include on-chain flows, validator telemetry, oracle deviations, and secondary-market microstructure. Outputs are transparent: assumptions, parameters, and backtests sit alongside a living white paper and code. The first users are funds, treasuries, and DAOs that need defensible sizing and monitoring, not marketing APYs. The aim is simple: earn premia that are priced, sized, and governed.