diff --git a/Cargo.toml b/Cargo.toml
index 7e726fb..4367aeb 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -3,6 +3,7 @@ members = [
   "polynomial",
   "univariate-polynomial-iop-zerotest",
   "halo2-trials",
+  "[Rfc1321]message-digest-v5-hash",
   "[Sha97]shamir-secret-sharing",
   "[Fel87]feldman-verifiable-secret-sharing",
   "[Sch91]schnorr-discrete-log-proof-of-knowledge",
@@ -28,3 +29,4 @@ rand_core = "0.6.4"
 rand = "0.8.5"
 rand_chacha = "0.3.1"
 simba = "0.8.1"
+itertools = "0.12.1"
diff --git a/README.md b/README.md
index f4be4e8..636ace2 100644
--- a/README.md
+++ b/README.md
@@ -11,6 +11,7 @@ cd Cryptography-Research && cargo test
 ```
 
 ## References
-- **\[Sha97\]**: Shamir's secret sharing https://apps.dtic.mil/sti/pdfs/ADA069397.pdf.
-- **\[Fel87\]**: Feldman's verifiable secret sharing https://www.zkdocs.com/docs/zkdocs/protocol-primitives/verifiable-secret-sharing/
-- **\[Sch91\]**: Schnorr's DLog PoK https://www.zkdocs.com/docs/zkdocs/zero-knowledge-protocols/schnorr/
+- **\[Sha97\]**: [Shamir's secret sharing](https://apps.dtic.mil/sti/pdfs/ADA069397.pdf)
+- **\[Fel87\]**: [Feldman's verifiable secret sharing](https://www.zkdocs.com/docs/zkdocs/protocol-primitives/verifiable-secret-sharing/)
+- **\[Sch91\]**: [Schnorr's DLog PoK](https://www.zkdocs.com/docs/zkdocs/zero-knowledge-protocols/schnorr/)
+- **\[rfc1321\]**: [Message Digest v5 hashing function](https://datatracker.ietf.org/doc/html/rfc1321)
diff --git a/[rfc1321]message-digest-v5-hash/Cargo.toml b/[rfc1321]message-digest-v5-hash/Cargo.toml
new file mode 100644
index 0000000..faac360
--- /dev/null
+++ b/[rfc1321]message-digest-v5-hash/Cargo.toml
@@ -0,0 +1,7 @@
+[package]
+edition = "2021"
+name = "message-digest-5"
+version = "0.1.0"
+
+[dependencies]
+itertools = { workspace = true }
diff --git a/[rfc1321]message-digest-v5-hash/README.md b/[rfc1321]message-digest-v5-hash/README.md
new file mode 100644
index 0000000..097bb03
--- /dev/null
+++ b/[rfc1321]message-digest-v5-hash/README.md
@@ -0,0 +1,5 @@
+# Message Digest version 5
+
+See associated info at: [here](https://hackmd.io/@sraj/zk-hashfunc-comparison)
+
+## References
diff --git a/[rfc1321]message-digest-v5-hash/src/lib.rs b/[rfc1321]message-digest-v5-hash/src/lib.rs
new file mode 100644
index 0000000..ec8c92c
--- /dev/null
+++ b/[rfc1321]message-digest-v5-hash/src/lib.rs
@@ -0,0 +1,80 @@
+/// A generalized trait for hashing systems using
+/// a Merkle–Damgård construction
+trait MerkleDamgard {
+    type InternalState;
+    type Chunk;
+    type HashOutput;
+
+    /// An MD-compliant input padding logic
+    fn pad_input(message: &[u8]) -> Vec<Self::Chunk>;
+
+    /// Compressor step to consume a chunk and affect the state
+    fn apply_compressor(state: &mut Self::InternalState, chunk: Self::Chunk);
+
+    /// Final output producer
+    fn finalize() -> Self::HashOutput;
+}
+
+struct MessageDigestV5 {
+    round_constants: [u32; 64],
+    shift_amounts: [u32; 64],
+    initialization_state: [u32; 4],
+}
+
+impl MessageDigestV5 {
+    #[rustfmt::skip]
+    pub fn new() -> Self {
+        // The table formula function:
+        // K[i] = floor(2^32 * abs(sin(i))
+        fn round_constant_generator(i: u32) -> u32 {
+            let x: f64 = i as f64;
+            let sin_eval = x.sin().abs();
+
+            // note: 4294967296 == 2^32
+            (4294967296.0 * sin_eval) as u32
+        }
+
+        Self {
+            round_constants: (0..64)
+                .map(|x| round_constant_generator(x+1))
+                .collect::<Vec<u32>>()[0..64]
+                .try_into()
+                .unwrap(),
+            shift_amounts: [
+                [7, 12, 17, 22].into_iter().cycle().take(16).collect::<Vec<u32>>(),
+                [5,  9, 14, 20].into_iter().cycle().take(16).collect::<Vec<u32>>(),
+                [4, 11, 16, 23].into_iter().cycle().take(16).collect::<Vec<u32>>(),
+                [6, 10, 15, 21].into_iter().cycle().take(16).collect::<Vec<u32>>()
+            ].concat()[0..64]
+            .try_into()
+            .unwrap(),
+            initialization_state: [0x67452301u32, 0xefcdab89u32, 0x98badcfeu32, 0x10325476u32],
+        }
+    }
+}
+
+impl MerkleDamgard for MessageDigestV5 {
+    type InternalState = [u32; 4];
+    type Chunk = u32;
+    type HashOutput = [u32; 4];
+
+    fn pad_input(message: &[u8]) -> Vec<Self::Chunk> {
+        todo!()
+    }
+
+    fn apply_compressor(state: &mut Self::InternalState, chunk: Self::Chunk) {
+        todo!()
+    }
+
+    fn finalize() -> Self::HashOutput {
+        todo!()
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    #[test]
+    fn two() {
+        assert!(2 == 2);
+    }
+}