Changes in version 0.1.0 (2026-11-13) Initial CRAN release. Features - ds.EstimateAte() orchestrates federated ATE estimation across K independent studies using arm-specific OLS models fitted via ds.glm(). - compute_variance argument (default TRUE) returns a delta-method variance estimate and 95% confidence interval assembled from per-server residual sums of squares and projected scatter scalars, with no additional communication round. Set to FALSE to limit server disclosure to the three scalars strictly needed for the point estimate (n_k, n_k_1, tau_k). - heteroscedastic_arms argument (default FALSE) estimates arm-specific noise variances \eqn{\sigma_1^2} and \eqn{\sigma_0^2} rather than a pooled \eqn{\sigma^2}, adjusting the variance formula in both the delta-method and homogeneous closed-form branches. - heterogeneous argument (default TRUE) uses the leverage-corrected delta-method variance (valid under covariate shift and heterogeneous treatment probabilities across sites). Set to FALSE for the simpler homogeneous closed form. - study_effects argument (default FALSE) enables the adjusted generalised difference estimator for settings where study membership directly shifts the outcome. Appends K-1 integer study-dummy columns server-side via addStudyIdDS() and adjusts degrees of freedom accordingly. - Input validation helpers .check_datasources(), .check_args(), and .check_string() give informative errors on bad arguments. - .check_sample_sizes() warns when either federated arm size falls below 5*(d+1), indicating the asymptotic approximation may be unreliable.