diff --git a/.ci/requirements.txt b/.ci/requirements.txt
index 9c717358d40e1bfa65a49b66e4f4b8e23c435b50..de7d3a90aebbfb30c043492b7a6013e7b4a7685f 100644
--- a/.ci/requirements.txt
+++ b/.ci/requirements.txt
@@ -5,6 +5,7 @@ bioconductor-biocstyle
 r-htmltools
 r-flexdashboard
 r-glue
+r-leaflet
 r-knitr
 r-magrittr
 r-stringi