Fast Fixed-Effects Estimations R package fixest version 0.14.2 CRAN Task View: CausalInference (https://CRAN.R-project.org/view=CausalInference) CRAN Task View: Econometrics (https://CRAN.R-project.org/view=Econometrics) Fast and user-friendly estimation of econometric models with multiple fixed-effects. Includes ordinary least squares (OLS), instrumental variables (IV), generalized linear models (GLM), maximum likelihood estimation (ML), and the negative binomial. The core of the package is based on optimized parallel C++ code, scaling especially well for large data sets. The method to obtain the fixed-effects coefficients is based on Bergé, Butts, McDermott (2026) <doi:10.48550/arXiv.2601.21749>. Further provides tools to export and view the results of several estimations with intuitive design to change the standard-errors. Software Depends: R(>= 3.5.0) Imports: stats, graphics, grDevices, tools, utils, methods, numDeriv, nlme, sandwich, Rcpp(>= 1.0.5), dreamerr(>= 1.4.0), stringmagic(>= 1.2.0) LinkingTo: Rcpp Suggests: knitr, rmarkdown, data.table, plm, MASS, pander, ggplot2, lfe, tinytex, pdftools, emmeans, estimability, AER, Matrix Laurent Berge <laurent.berge@u-bordeaux.fr> Comprehensive R Archive Network (CRAN) Laurent Berge [aut, cre], Sebastian Krantz [ctb], Grant McDermott [ctb] (ORCID: <https://orcid.org/0000-0001-7883-8573>), Russell Lenth [ctb], Kyle Butts [ctb] GPL-3 2026-06-26 application/tgz https://CRAN.R-project.org/package=fixest doi:10.32614/CRAN.package.fixest