diff --git a/Cargo.lock b/Cargo.lock
index 412d141..b04294d 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -227,6 +227,13 @@ version = "1.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "acbf1af155f9b9ef647e42cdc158db4b64a1b61f743629225fde6f3e0be2a7c7"
 
+[[package]]
+name = "constants"
+version = "0.1.0"
+dependencies = [
+ "syntest",
+]
+
 [[package]]
 name = "core-foundation"
 version = "0.9.4"
diff --git a/challenges/challenges.json b/challenges/challenges.json
index ac54500..42ce0a6 100644
--- a/challenges/challenges.json
+++ b/challenges/challenges.json
@@ -7,7 +7,7 @@
     "language": "RUST",
     "difficulty": "BEGINNER",
     "track": "RUST_BASICS",
-    "tags": [],
+    "tags": ["function", "string", "output"],
     "created_at": "2024-04-20T00:00:00Z",
     "updated_at": "2024-04-20T00:00:00Z"
   },
@@ -29,12 +29,24 @@
     "slug": "mutable-variables",
     "short_description": "Define and modify mutable variables in Rust.",
     "language": "RUST",
-    "difficulty": "EASY",
+    "difficulty": "BEGINNER",
     "track": "RUST_BASICS",
-    "tags": [],
+    "tags": ["variables", "mutability"],
     "created_at": "2024-06-08T00:00:00Z",
     "updated_at": "2024-06-08T00:00:00Z"
   },
+  {
+    "id": 24,
+    "title": "Constants",
+    "slug": "constants",
+    "short_description": "Learn how to define and use constants in Rust.",
+    "language": "RUST",
+    "difficulty": "BEGINNER",
+    "track": "RUST_BASICS",
+    "tags": ["constants", "definition"],
+    "created_at": "2024-06-09T00:00:00Z",
+    "updated_at": "2024-06-09T00:00:00Z"
+  },
   {
     "id": 2,
     "title": "Character counting string",
diff --git a/challenges/constants/Cargo.toml b/challenges/constants/Cargo.toml
new file mode 100644
index 0000000..d276ed1
--- /dev/null
+++ b/challenges/constants/Cargo.toml
@@ -0,0 +1,7 @@
+[package]
+name = "constants"
+version = "0.1.0"
+edition = "2021"
+
+[dev-dependencies]
+syntest = { path = "../../crates/syntest" }
diff --git a/challenges/constants/src/lib.rs b/challenges/constants/src/lib.rs
new file mode 100644
index 0000000..2bcd954
--- /dev/null
+++ b/challenges/constants/src/lib.rs
@@ -0,0 +1,5 @@
+const MAX_SIZE: i32 = 100;
+
+pub fn main() -> i32 {
+    MAX_SIZE
+}
diff --git a/challenges/constants/src/starter.rs b/challenges/constants/src/starter.rs
new file mode 100644
index 0000000..96d30d7
--- /dev/null
+++ b/challenges/constants/src/starter.rs
@@ -0,0 +1,6 @@
+// Define a constant MAX_SIZE with a value of 100.
+// Your code here
+
+pub fn main() -> i32 {
+    MAX_SIZE
+}
diff --git a/challenges/constants/tests/tests.rs b/challenges/constants/tests/tests.rs
new file mode 100644
index 0000000..efee0c2
--- /dev/null
+++ b/challenges/constants/tests/tests.rs
@@ -0,0 +1,42 @@
+#[cfg(test)]
+mod tests {
+    use constants::*;
+    use syntest::Syntest;
+
+    #[test]
+    fn compiles() {
+        assert_eq!(main(), 100, "Expected main() to return 100");
+    }
+
+    #[test]
+    fn test_constants() {
+        let syntest = Syntest::from("./src/lib.rs");
+
+        let const_to_exist = ["MAX_SIZE"];
+        let constants = syntest.constant.constants();
+
+        let mut success = false;
+        for const_name in const_to_exist.iter() {
+            constants.iter().for_each(|con| {
+                if con.ident.to_string() != *const_name {
+                    return;
+                }
+
+                assert_eq!(
+                    con.ty,
+                    syntest::parse_quote! { i32 },
+                    "Expected type i32 for constant MAX_SIZE"
+                );
+                assert_eq!(
+                    con.expr,
+                    syntest::parse_quote! { 100 },
+                    "Expected value 100 for constant MAX_SIZE"
+                );
+
+                success = true;
+            })
+        }
+
+        assert!(success, "Expected constant MAX_SIZE to exist");
+    }
+}