diff --git a/Cargo.lock b/Cargo.lock
index 55dfba9..6316c30 100755
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -16,6 +16,7 @@ name = "algorithms"
 version = "0.1.0"
 dependencies = [
  "criterion",
+ "generic-array",
  "iai",
 ]
 
@@ -307,6 +308,15 @@ dependencies = [
  "num",
 ]
 
+[[package]]
+name = "generic-array"
+version = "1.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e8c8444bc9d71b935156cc0ccab7f622180808af7867b1daae6547d773591703"
+dependencies = [
+ "typenum",
+]
+
 [[package]]
 name = "half"
 version = "1.8.3"
@@ -788,6 +798,12 @@ dependencies = [
  "serde_json",
 ]
 
+[[package]]
+name = "typenum"
+version = "1.18.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1dccffe3ce07af9386bfd29e80c0ab1a8205a2fc34e4bcd40364df902cfa8f3f"
+
 [[package]]
 name = "unicode-ident"
 version = "1.0.18"
diff --git a/crates/algorithms/Cargo.toml b/crates/algorithms/Cargo.toml
index d677abe..7e4c4b1 100755
--- a/crates/algorithms/Cargo.toml
+++ b/crates/algorithms/Cargo.toml
@@ -4,6 +4,7 @@ version = "0.1.0"
 edition = "2024"
 
 [dependencies]
+generic-array = "1.2.0"
 
 [dev-dependencies]
 criterion = "0.3"
diff --git a/crates/algorithms/src/hash/ffi/sha2.rs b/crates/algorithms/src/hash/ffi/sha2.rs
index 6bde16d..d0f0a56 100644
--- a/crates/algorithms/src/hash/ffi/sha2.rs
+++ b/crates/algorithms/src/hash/ffi/sha2.rs
@@ -1,6 +1,6 @@
 use crate::ffi::{ref_to_ptr, ref_to_ptr_mut};
 
-use super::super::sha2::*;
+use super::super::sha2::{DIGEST256_EMPTY, Digest256, SHA2_256_BLOCK_SIZE};
 
 #[repr(C)]
 #[allow(non_camel_case_types)]
@@ -17,8 +17,8 @@ pub enum SHA2Result {
 
 #[repr(C)]
 #[derive(Debug, PartialEq, Eq, Clone, Copy, Hash)]
-pub struct SHA2Context {
-    pub intermediate_hash: Digest,
+pub struct Sha2_256Context {
+    pub intermediate_hash: Digest256,
     pub length_low: u32,
     pub length_high: u32,
     pub message_block_index: i16,
@@ -27,10 +27,10 @@ pub struct SHA2Context {
     pub corrupted: bool,
 }
 
-impl SHA2Context {
+impl Sha2_256Context {
     pub fn new() -> Self {
         Self {
-            intermediate_hash: DIGEST_EMPTY,
+            intermediate_hash: DIGEST256_EMPTY,
             length_low: 0,
             length_high: 0,
             message_block_index: 0,
@@ -41,7 +41,7 @@ impl SHA2Context {
     }
 }
 
-impl Default for SHA2Context {
+impl Default for Sha2_256Context {
     fn default() -> Self {
         Self::new()
     }
@@ -50,40 +50,44 @@ impl Default for SHA2Context {
 mod ffi {
     use super::*;
     unsafe extern "C" {
-        pub fn sha2_256_oneshot(data: *const u8, len: usize, digest: *mut Digest) -> SHA2Result;
-        pub fn sha2_256_reset(context: *mut SHA2Context) -> SHA2Result;
-        pub fn sha2_256_input(context: *mut SHA2Context, data: *const u8, len: usize)
+        pub fn sha2_256_oneshot(data: *const u8, len: usize, digest: *mut Digest256) -> SHA2Result;
+        pub fn sha2_256_reset(context: *mut Sha2_256Context) -> SHA2Result;
+        pub fn sha2_256_input(
+            context: *mut Sha2_256Context,
+            data: *const u8,
+            len: usize,
+        ) -> SHA2Result;
+        pub fn sha2_256_result(context: *mut Sha2_256Context, digest: *mut Digest256)
         -> SHA2Result;
-        pub fn sha2_256_result(context: *mut SHA2Context, digest: *mut Digest) -> SHA2Result;
     }
 }
 
 #[inline]
-pub fn sha2_256_oneshot(data: &[u8]) -> Result<Digest, SHA2Result> {
-    let mut digest: Digest = DIGEST_EMPTY;
+pub fn sha2_256_oneshot(data: &[u8]) -> Result<Digest256, SHA2Result> {
+    let mut digest: Digest256 = DIGEST256_EMPTY;
     let res =
         unsafe { ffi::sha2_256_oneshot(ref_to_ptr(data), data.len(), ref_to_ptr_mut(&mut digest)) };
     to_res(digest, res)
 }
 
-pub fn sha2_256_reset(context: &mut SHA2Context) -> Result<(), SHA2Result> {
+pub fn sha2_256_reset(context: &mut Sha2_256Context) -> Result<(), SHA2Result> {
     let res = unsafe { ffi::sha2_256_reset(ref_to_ptr_mut(context)) };
     to_res((), res)
 }
 
-pub fn sha2_256_input(context: &mut SHA2Context, data: &[u8]) -> Result<(), SHA2Result> {
+pub fn sha2_256_input(context: &mut Sha2_256Context, data: &[u8]) -> Result<(), SHA2Result> {
     let res = unsafe { ffi::sha2_256_input(ref_to_ptr_mut(context), ref_to_ptr(data), data.len()) };
     to_res((), res)
 }
 
-pub fn sha2_256_result(context: &mut SHA2Context) -> Result<Digest, SHA2Result> {
-    let mut digest: Digest = DIGEST_EMPTY;
+pub fn sha2_256_result(context: &mut Sha2_256Context) -> Result<Digest256, SHA2Result> {
+    let mut digest: Digest256 = DIGEST256_EMPTY;
     let res = unsafe { ffi::sha2_256_result(ref_to_ptr_mut(context), ref_to_ptr_mut(&mut digest)) };
     to_res(digest, res)
 }
 
 #[inline]
-fn to_res<T>(if_ok: T, res: SHA2Result) -> Result<T, SHA2Result> {
+pub(crate) fn to_res<T>(if_ok: T, res: SHA2Result) -> Result<T, SHA2Result> {
     if res == SHA2Result::shaSuccess {
         Ok(if_ok)
     } else {
@@ -91,26 +95,28 @@ fn to_res<T>(if_ok: T, res: SHA2Result) -> Result<T, SHA2Result> {
     }
 }
 
+// NOTE: this SHA2_256 implementation does not suit core::hash::Hasher in Rust, since that expects
+// a finish method with &self and that the hasher can be used after finish.
+
 #[cfg(test)]
 mod test {
-    use crate::digest;
-    use crate::hash::Digest;
+    use crate::hash::Digest256;
     use crate::hash::ffi::sha2_256_oneshot;
 
-    const TEST_VALUES: &[(&str, Digest)] = &[
+    const TEST_VALUES: &[(&str, Digest256)] = &[
         (
             "AAAA",
-            digest!(
+            [
                 0x63c1dd95, 0x1ffedf6f, 0x7fd968ad, 0x4efa39b8, 0xed584f16, 0x2f46e715, 0x114ee184,
-                0xf8de9201
-            ),
+                0xf8de9201,
+            ],
         ),
         (
             "BAAA",
-            digest!(
+            [
                 0x49e3cd45, 0x27c96cdc, 0x010160ff, 0x08520e0c, 0xb63c6ef8, 0xc4e7d486, 0x08995343,
-                0x7f83a159
-            ),
+                0x7f83a159,
+            ],
         ),
     ];
 
diff --git a/crates/algorithms/src/hash/sha2.rs b/crates/algorithms/src/hash/sha2.rs
index f0bbb9d..75c8cf7 100644
--- a/crates/algorithms/src/hash/sha2.rs
+++ b/crates/algorithms/src/hash/sha2.rs
@@ -1,15 +1,107 @@
+use generic_array::GenericArray;
+
+use crate::hash::{ffi::SHA2Result, sha2::sealed::SHA2Mode};
+
 pub const SHA2_256_HASH_BITS: usize = 256;
 pub const SHA2_256_HASH_BYTES: usize = SHA2_256_HASH_BITS / 8;
 pub const SHA2_256_HASH_PARTS: usize = SHA2_256_HASH_BYTES / 4 /* storing with u32 */;
 pub const SHA2_256_BLOCK_SIZE: usize = 2 * SHA2_256_HASH_BYTES;
 
-pub type Digest = [u32; SHA2_256_HASH_PARTS];
+pub type Digest256 = [u32; SHA2_256_HASH_PARTS];
+pub(crate) const DIGEST256_EMPTY: Digest256 = [0; SHA2_256_HASH_PARTS];
 
-#[macro_export]
-macro_rules! digest {
-    ($($block:literal$(,)?)+) => {
-        [$($block,)+ ]
-    };
+pub struct Mode256;
+mod sealed {
+    use generic_array::{ArrayLength, GenericArray};
+
+    use super::Mode256;
+    pub trait SHA2Mode {
+        type HashBits: ArrayLength;
+        type HashBytes: ArrayLength;
+        type HashParts: ArrayLength;
+        type BlockSize: ArrayLength;
+        type Digest: AsRef<[u32]> + AsMut<[u32]>;
+        type Block: AsRef<[u8]> + AsMut<[u8]>;
+    }
+    impl SHA2Mode for Mode256 {
+        type HashBits = generic_array::typenum::U256;
+        type HashBytes = generic_array::typenum::U32;
+        type HashParts = generic_array::typenum::U8;
+        type BlockSize = generic_array::typenum::U512;
+        type Digest = GenericArray<u32, Self::HashParts>;
+        type Block = GenericArray<u8, Self::BlockSize>;
+    }
+    impl Mode256 {}
 }
 
-pub(crate) const DIGEST_EMPTY: Digest = [0; SHA2_256_HASH_PARTS];
+#[derive(Debug, PartialEq, Eq, Clone, Hash)]
+pub struct SHA2Context<M: sealed::SHA2Mode> {
+    intermediate_hash: GenericArray<u32, M::HashParts>,
+    block: GenericArray<u8, M::BlockSize>,
+    block_idx: usize,
+}
+
+impl<M: sealed::SHA2Mode> SHA2Context<M> {
+    pub fn new() -> Self {
+        Self {
+            intermediate_hash: Default::default(),
+            block: Default::default(),
+            block_idx: Default::default(),
+        }
+    }
+
+    pub fn clear(&mut self) {
+        *self = Self::new();
+    }
+
+    pub fn input(&mut self, data: &[u8]) -> Result<(), SHA2Result> {
+        todo!()
+    }
+
+    pub fn finish(self) -> Result<M::Digest, SHA2Result> {
+        todo!()
+    }
+}
+
+impl<M: sealed::SHA2Mode> Default for SHA2Context<M> {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
+pub fn sha2_oneshot<M: sealed::SHA2Mode>(data: &[u8]) -> Result<M::Digest, SHA2Result> {
+    todo!()
+}
+
+pub fn sha2_256_oneshot(data: &[u8]) -> Result<Digest256, SHA2Result> {
+    sha2_oneshot::<Mode256>(data).map(|dig| dig.into_array())
+}
+
+#[cfg(test)]
+mod test {
+    use super::*;
+
+    const TEST_VALUES: &[(&str, Digest256)] = &[
+        (
+            "AAAA",
+            [
+                0x63c1dd95, 0x1ffedf6f, 0x7fd968ad, 0x4efa39b8, 0xed584f16, 0x2f46e715, 0x114ee184,
+                0xf8de9201,
+            ],
+        ),
+        (
+            "BAAA",
+            [
+                0x49e3cd45, 0x27c96cdc, 0x010160ff, 0x08520e0c, 0xb63c6ef8, 0xc4e7d486, 0x08995343,
+                0x7f83a159,
+            ],
+        ),
+    ];
+
+    #[test]
+    fn test_check() {
+        for (input, expected_output) in TEST_VALUES.iter().copied() {
+            assert_eq!(sha2_256_oneshot(input.as_bytes()), Ok(expected_output))
+        }
+    }
+}