diff --git a/src/day12.rs b/src/day12.rs
new file mode 100644
index 0000000..b473287
--- /dev/null
+++ b/src/day12.rs
@@ -0,0 +1,36 @@
+use aoc_runner_derive::{aoc, aoc_generator};
+use rstest::rstest;
+
+#[aoc_generator(day12)]
+fn parse(input: &str) -> String {
+    todo!()
+}
+
+#[aoc(day12, part1)]
+fn part1(input: &str) -> u64 {
+    todo!()
+}
+
+#[aoc(day12, part2)]
+fn part2(input: &str) -> u64 {
+    todo!()
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    const EXAMPLE: &str = "";
+
+    #[rstest]
+    #[case(EXAMPLE, 0)]
+    fn part1_example(#[case] input: &str, #[case] expected: u64) {
+        assert_eq!(part1(&parse(EXAMPLE)), 0);
+    }
+
+    #[rstest]
+    #[case(EXAMPLE, 0)]
+    fn part2_example(#[case] input: &str, #[case] expected: u64) {
+        assert_eq!(part2(&parse(EXAMPLE)), 0);
+    }
+}
diff --git a/src/lib.rs b/src/lib.rs
index 8afe3bf..5ed53fe 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -1,6 +1,7 @@
 mod day1;
 mod day10;
 mod day11;
+mod day12;
 mod day2;
 mod day3;
 mod day4;