diff --git a/.github/workflows/build_test.yml b/.github/workflows/build_test.yml
index ba7611e..7c1ae6a 100644
--- a/.github/workflows/build_test.yml
+++ b/.github/workflows/build_test.yml
@@ -23,4 +23,4 @@ jobs:
     - name: Run unit tests
       run: cargo test
     - name: Build and run sample/rust
-      run: cd samples/rust && cargo run && cd ../..
+      run: cd samples/rust && cargo run && cargo test && cd ../..
diff --git a/samples/python/main.py b/samples/python/main.py
index df8fcb9..b6be45a 100644
--- a/samples/python/main.py
+++ b/samples/python/main.py
@@ -3,7 +3,7 @@
 def sample():
     print("Dlccryptlib sample app, Python")
 
-    entropy_hex = "99d33a674ce99d33a674ce99d33a674c" # oil x 12
+    entropy_hex = "00000000000000000000000000000001" # abandon x 11 actual
     network = "signet";
 
     xpub = dlccryptlib_py.init_with_entropy(entropy_hex, network)
diff --git a/samples/rust/src/main.rs b/samples/rust/src/main.rs
index 3ec744b..82ef91c 100644
--- a/samples/rust/src/main.rs
+++ b/samples/rust/src/main.rs
@@ -1,12 +1,16 @@
 ///
 ///  Sample Rust program to use dlccryptlib.
 ///
+
+#[cfg(test)]
+mod test_lib;
+
 use dlccryptlib;
 
 fn main() {
     println!("Dlccryptlib sample (Rust)");
 
-    let entropy_hex = "99d33a674ce99d33a674ce99d33a674c"; // oil x 12
+    let entropy_hex = "00000000000000000000000000000001"; // abandon x 11 actual
     let network = "signet";
 
     let xpub = dlccryptlib::init_with_entropy_intern(entropy_hex, network).unwrap();
diff --git a/samples/rust/src/test_lib.rs b/samples/rust/src/test_lib.rs
new file mode 100644
index 0000000..d81c3bc
--- /dev/null
+++ b/samples/rust/src/test_lib.rs
@@ -0,0 +1,54 @@
+///
+///  Sample Rust program to use dlccryptlib.
+///
+use dlccryptlib;
+
+const DUMMY_ENTROPY_STR: &str = "00000000000000000000000000000001";
+const DUMMY_HASH07_STR: &str = "0000000000000000000000000000000000000000000000000000000000000007";
+const NETWORK_SIGNET: &str = "signet";
+const DEFAULT_NETWORK: &str = NETWORK_SIGNET;
+
+#[test]
+fn test_init_with_entropy() {
+    let xpub = dlccryptlib::init_with_entropy_intern(DUMMY_ENTROPY_STR, DEFAULT_NETWORK).unwrap();
+    assert_eq!(
+            xpub,
+            "tpubDCxVvuZwEu4oZypCT3pzos1MUoVJyjTHjfrhKFXNBkAEqBmkkzEb2dUgzpZmBWbd6wZnNmm3Ex2suMnEFUMmayH2a6S49R4pTnoQttGrxUm"
+        );
+}
+
+#[test]
+fn test_get_public_key() {
+    let _xpub = dlccryptlib::init_with_entropy_intern(DUMMY_ENTROPY_STR, DEFAULT_NETWORK).unwrap();
+
+    let pubkey0 = dlccryptlib::get_public_key_intern(0).unwrap();
+    assert_eq!(
+        pubkey0.to_string(),
+        "031941e84b8d111e094aefc46e7181757c93a1da87c93ab519a40d9d765176e704"
+    );
+
+    let pubkey3 = dlccryptlib::get_public_key_intern(3).unwrap();
+    assert_eq!(
+        pubkey3.to_string(),
+        "02a9569875400df2b7af9360fc5025de31fcd48ca8b658d61e535c3ff2f55aa128"
+    );
+}
+
+#[test]
+fn test_sign_hash_ecdsa() {
+    let _xpub = dlccryptlib::init_with_entropy_intern(DUMMY_ENTROPY_STR, DEFAULT_NETWORK).unwrap();
+
+    let pubkey3 = dlccryptlib::get_public_key_intern(3).unwrap();
+    assert_eq!(
+        pubkey3.to_string(),
+        "02a9569875400df2b7af9360fc5025de31fcd48ca8b658d61e535c3ff2f55aa128"
+    );
+
+    let hash = DUMMY_HASH07_STR;
+    let sig = dlccryptlib::sign_hash_ecdsa_intern(&hash, 3, &pubkey3).unwrap();
+
+    assert!(sig.len() >= 140 && sig.len() <= 146);
+
+    // negative test, wrong index
+    assert!(dlccryptlib::sign_hash_ecdsa_intern(&hash, 31, &pubkey3).is_err());
+}