diff --git a/Cargo.lock b/Cargo.lock
new file mode 100644
index 0000000..0672745
--- /dev/null
+++ b/Cargo.lock
@@ -0,0 +1,11 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+version = 4
+
+[[package]]
+name = "achievement-counter-cli"
+version = "0.1.0"
+
+[[package]]
+name = "achievement-counter-core"
+version = "0.1.0"
diff --git a/Cargo.toml b/Cargo.toml
new file mode 100644
index 0000000..9c91888
--- /dev/null
+++ b/Cargo.toml
@@ -0,0 +1,6 @@
+[workspace]
+
+members = [
+    "cli",
+    "core",
+]
diff --git a/cli/Cargo.toml b/cli/Cargo.toml
new file mode 100644
index 0000000..bd25205
--- /dev/null
+++ b/cli/Cargo.toml
@@ -0,0 +1,6 @@
+[package]
+name = "achievement-counter-cli"
+version = "0.1.0"
+edition = "2024"
+
+[dependencies]
diff --git a/cli/src/main.rs b/cli/src/main.rs
new file mode 100644
index 0000000..e7a11a9
--- /dev/null
+++ b/cli/src/main.rs
@@ -0,0 +1,3 @@
+fn main() {
+    println!("Hello, world!");
+}
diff --git a/core/Cargo.toml b/core/Cargo.toml
new file mode 100644
index 0000000..04fcc75
--- /dev/null
+++ b/core/Cargo.toml
@@ -0,0 +1,6 @@
+[package]
+name = "achievement-counter-core"
+version = "0.1.0"
+edition = "2024"
+
+[dependencies]
diff --git a/core/src/lib.rs b/core/src/lib.rs
new file mode 100644
index 0000000..b93cf3f
--- /dev/null
+++ b/core/src/lib.rs
@@ -0,0 +1,14 @@
+pub fn add(left: u64, right: u64) -> u64 {
+    left + right
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn it_works() {
+        let result = add(2, 2);
+        assert_eq!(result, 4);
+    }
+}