diff --git a/exe/dune b/exe/dune
new file mode 100644
index 0000000..5f933ef
--- /dev/null
+++ b/exe/dune
@@ -0,0 +1,4 @@
+(executable
+ (public_name aoc)
+ (name main)
+ (libraries aoc))
diff --git a/exe/main.ml b/exe/main.ml
new file mode 100644
index 0000000..5c44db9
--- /dev/null
+++ b/exe/main.ml
@@ -0,0 +1,6 @@
+open Aoc
+
+let () =
+  Day1.print ();
+  Day2.print ()
+;;
diff --git a/src/dune b/src/dune
index 0682cc8..17ab1e5 100644
--- a/src/dune
+++ b/src/dune
@@ -1,5 +1,4 @@
-(executable
- (public_name aoc)
- (name main)
+(library
+ (name aoc)
  (libraries stdio re)
  (preprocess (pps ppx_regexp)))
diff --git a/src/main.ml b/src/main.ml
deleted file mode 100644
index 754d190..0000000
--- a/src/main.ml
+++ /dev/null
@@ -1,4 +0,0 @@
-let () =
-  Day1.print;
-  Day2.print
-;;