diff --git a/tests/testthat/test-unit_zi.R b/tests/testthat/test-unit_zi.R
index 01ef17d..0ac70b3 100644
--- a/tests/testthat/test-unit_zi.R
+++ b/tests/testthat/test-unit_zi.R
@@ -1,5 +1,7 @@
 library(saeczi)
 
+install.packages("lme4", type = "source")
+
 data(pop)
 data(samp)