Temporal Parametric Hazard Modeling // Provides native R implementations of the multiphase parametric hazard model of Blackstone, Naftel, and Turner (1986) doi:10.1080/01621459.1986.10478314 with a focus on behavioral parity, transparent numerics, and reproducible validation against reference outputs from the original 'C'/'SAS' HAZARD program, originally developed at the University of Alabama at Birmingham (UAB). The 'SAS'/'C' code and this R package are currently developed and maintained at The Cleveland Clinic Foundation, and the R code was wholly developed at The Cleveland Clinic Foundation. The generalized temporal decomposition family extends to longitudinal mixed-effects settings (Rajeswaran et al. 2018 doi:10.1177/0962280215623583). The package is intentionally implemented in pure R first; performance-critical paths may later be accelerated with 'Rcpp' without changing the public interface.