Explicit Key Assumptions for Flat-File Data R package keyed version 0.2.0 Helps make implicit data assumptions explicit by attaching keys to flat-file data that error when those assumptions are violated. Designed for CSV-first workflows without database infrastructure or version control. Provides key definition, assumption checks, join diagnostics, and automatic drift detection via watched data frames that snapshot before each transformation and report cell-level changes. Software Depends: R (>= 4.1.0) Imports: cli, dplyr (>= 1.0.0), digest, lifecycle (>= 1.0.0), pillar, rlang (>= 1.0.0), tibble, vctrs (>= 0.5.0) Suggests: joinspy, knitr, rmarkdown, testthat (>= 3.0.0), uuid Gilles Colling <gilles.colling051@gmail.com> Comprehensive R Archive Network (CRAN) Gilles Colling [aut, cre, cph] (ORCID: <https://orcid.org/0000-0003-3070-6066>) MIT + file LICENSE (https://CRAN.R-project.org/package=keyed/LICENSE) 2026-02-25 application/tgz https://CRAN.R-project.org/package=keyed doi:10.32614/CRAN.package.keyed en-US