diff --git a/build.sh b/build.sh
index 5509389..9dc3f18 100755
--- a/build.sh
+++ b/build.sh
@@ -3,10 +3,12 @@
 set -Eeuo pipefail
 shopt -s expand_aliases
 
-rm -rf bin && mkdir -p bin && javac --enable-preview --source 23 -d bin snippets/*.java
+rm -rf bin && mkdir -p bin && javac --enable-preview --source 23 -Xlint:all -d bin snippets/*.java
 
 alias marp="docker run --rm -v $PWD:/home/marp/app/ -e MARP_USER="$(id -u):$(id -g)" -e LANG=$LANG marpteam/marp-cli"
 
 marp slides.md -o slides.html
 marp slides.md -o slides.pdf
+marp slides_en.md -o slides_en.html
+marp slides_en.md -o slides_en.pdf
 
diff --git a/snippets/List.java b/snippets/List.java
index c0e0995..48ee6bc 100644
--- a/snippets/List.java
+++ b/snippets/List.java
@@ -45,6 +45,7 @@
         };
     }
 
+    @SafeVarargs
     static <T> List<T> of(T...values) {
         List<T> list = empty();
         for (T value : values) {