diff --git a/src/error.rs b/src/error.rs
new file mode 100644
index 0000000..4996c44
--- /dev/null
+++ b/src/error.rs
@@ -0,0 +1,9 @@
+//! Error types.
+
+#[derive(Debug)]
+pub enum Error {
+    InvalidStory(),
+    SourceError(&'static str),
+}
+
+pub type Result<T> = std::result::Result<T, Error>;
diff --git a/src/main.rs b/src/main.rs
index 79ea707..669cf15 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,5 +1,6 @@
 //! Main module.
 
+pub mod error;
 pub mod story;
 
 fn main() {