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+# ❗ This repository is deprecated and no longer updated
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+Stan's R packages are now built and distributed by our R-Universe organisation: https://stan-dev.r-universe.dev/builds
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+For more information, see [this forum announcement](https://discourse.mc-stan.org/t/announcement-stan-r-packages-repo-deprecated-moving-to-r-universe/35341)
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 # Repository for distributing (some) stan-dev R packages
 
 A place for publishing new versions of (some) `stan-dev` R packages before they reach CRAN and for `stan-dev` R packages and versions where releasing on CRAN is not a (current) goal. As of 2021-03-16 this is most relevant for `rstan`, where the CRAN version is unfortunately several releases behind and pushing a new version to CRAN has been difficult.