diff --git a/Cargo.toml b/Cargo.toml
index 6004a36..5cc9431 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -6,9 +6,18 @@ license = "MIT"
 
 [dependencies]
 
+[lints.rust]
+unsafe_code = "forbid"
+
 [lints.clippy]
 all = { level = "warn", priority = -1 }
 pedantic = { level = "warn", priority = -1 }
 allow_attributes_without_reason = "warn"
 cognitive_complexity = "warn"
 excessive_nesting = "warn"
+dbg_macro = "deny"
+todo = "deny"
+unimplemented = "deny"
+unwrap_used = "deny"
+indexing_slicing = "deny"
+expect_used = "deny"
diff --git a/clippy.toml b/clippy.toml
index a1a18f9..aef6df2 100644
--- a/clippy.toml
+++ b/clippy.toml
@@ -1,3 +1,6 @@
 too-many-arguments-threshold = 3
 excessive-nesting-threshold = 2
 cognitive-complexity-threshold = 15
+allow-unwrap-in-tests = true
+allow-expect-in-tests = true
+allow-indexing-slicing-in-tests = true
diff --git a/src/main.rs b/src/main.rs
index 7546a57..a120fb0 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,11 +1,17 @@
 fn main() {
-    println!("Hello, world!");
+    println!("{}", greeting());
+}
+
+fn greeting() -> &'static str {
+    "Hello, world!"
 }
 
 #[cfg(test)]
 mod tests {
+    use super::greeting;
+
     #[test]
-    fn it_works() {
-        assert!(true);
+    fn greeting_is_hello_world() {
+        assert_eq!(greeting(), "Hello, world!");
     }
 }