diff --git a/build.zig b/build.zig
index a0c4580..aa57813 100644
--- a/build.zig
+++ b/build.zig
@@ -24,16 +24,15 @@ pub fn build(b: *std.Build) void {
         .optimize = optimize,
     });
 
-    // // Add ssz.zig as a dependency to the library
-    // const ssz_dep = b.dependency(
-    //     "ssz.zig",
-    //     .{
-    //         .target = target,
-    //         .optimize = optimize,
-    //     },
-    // );
-    // lib.addLibraryPath(ssz_dep.path("src"));
-    // lib.addIncludePath(ssz_dep.path("src"));
+    // Add ssz.zig as a dependency to the library
+    const ssz_dep = b.dependency(
+        "zabi",
+        .{
+            .target = target,
+            .optimize = optimize,
+        },
+    );
+    lib.root_module.addImport("zabi", ssz_dep.module("zabi"));
 
     // This declares intent for the library to be installed into the standard
     // location when the user invokes the "install" step (the default step when
@@ -47,6 +46,7 @@ pub fn build(b: *std.Build) void {
         .optimize = optimize,
     });
 
+    exe.root_module.addImport("zabi", ssz_dep.module("zabi"));
     // This declares intent for the executable to be installed into the
     // standard location when the user invokes the "install" step (the default
     // step when running `zig build`).
@@ -83,6 +83,8 @@ pub fn build(b: *std.Build) void {
         .optimize = optimize,
     });
 
+    lib_unit_tests.root_module.addImport("zabi", ssz_dep.module("zabi"));
+
     const run_lib_unit_tests = b.addRunArtifact(lib_unit_tests);
 
     const exe_unit_tests = b.addTest(.{
diff --git a/build.zig.zon b/build.zig.zon
index 3b35062..fdda806 100644
--- a/build.zig.zon
+++ b/build.zig.zon
@@ -22,12 +22,10 @@
     // `zig build --fetch` can be used to fetch all dependencies of a package, recursively.
     // Once all dependencies are fetched, `zig build` no longer requires
     // internet connectivity.
-    .dependencies = .{
-        .@"ssz.zig" = .{
-            .url = "https://github.com/gballet/ssz.zig/archive/808c88aa6bd0f3d2e736774e4439afa24ab5377c.tar.gz",
-            .hash = "1220c73fadb1988c41aa54be104ce680812f833a6f6d53a5065f6e6db7ca73989d55",
-        },
-    },
+    .dependencies = .{ .zabi = .{
+        .url = "https://github.com/Raiden1411/zabi/archive/79c77aa4a39d41ed50033fd922f4d37c0f0638bb.tar.gz",
+        .hash = "122095aaf2d09e3286bf8b00b773b65c1632639de6c5005de881754df7c04efc7e98",
+    } },
     .paths = .{
         "build.zig",
         "build.zig.zon",
diff --git a/src/consensus/helpers/domain.zig b/src/consensus/helpers/domain.zig
new file mode 100644
index 0000000..d850850
--- /dev/null
+++ b/src/consensus/helpers/domain.zig
@@ -0,0 +1,57 @@
+const zabi = @import("zabi");
+const std = @import("std");
+const primitives = @import("../../primitives/types.zig");
+const consensus = @import("../../consensus/types.zig");
+
+/// computeForkDataRoot return the 32-byte fork data root for the ``current_version`` and ``genesis_validators_root``.
+/// This is used primarily in signature domains to avoid collisions across forks/chains.
+/// Spec pseudocode definition:
+/// def compute_fork_data_root(current_version: Version, genesis_validators_root: Root) -> Root:
+///     """
+///     Return the 32-byte fork data root for the ``current_version`` and ``genesis_validators_root``.
+///     This is used primarily in signature domains to avoid collisions across forks/chains.
+///     """
+///    return hash_tree_root(ForkData(
+///        current_version=current_version,
+///        genesis_validators_root=genesis_validators_root,
+///   ))
+pub fn computeForkDataRoot(current_version: primitives.Version, genesis_validators_root: primitives.Root) primitives.Root {
+    const fork_data = consensus.ForkData{
+        .current_version = current_version,
+        .genesis_validators_root = genesis_validators_root,
+    };
+
+    std.debug.print("ForkData: {}\n", .{fork_data});
+    // todo: implement hash_tree_root
+    return .{0} ** 32;
+}
+
+/// computeForkDigest returns the 4-byte fork digest for the `currentVersion` and `genesisValidatorsRoot`.
+/// This is a digest primarily used for domain separation on the p2p layer.
+/// 4-bytes suffices for practical separation of forks/chains.
+/// Spec pseudocode definition:
+/// def compute_fork_digest(current_version: Version, genesis_validators_root: Root) -> ForkDigest:
+///    """
+///    Return the 4-byte fork digest for the ``current_version`` and ``genesis_validators_root``.
+///    This is a digest primarily used for domain separation on the p2p layer.
+///    4-bytes suffices for practical separation of forks/chains.
+///    """
+///    return ForkDigest(compute_fork_data_root(current_version, genesis_validators_root)[:4])
+pub fn computeForkDigest(currentVersion: primitives.Version, genesisValidatorsRoot: primitives.Root) primitives.ForkDigest {
+    const forkDataRoot = computeForkDataRoot(currentVersion, genesisValidatorsRoot);
+    return forkDataRoot[0..4].*;
+}
+
+test "test computeForkDigest" {
+    const currentVersion = .{0} ** 4;
+    const genesisValidatorsRoot = .{0} ** 32;
+    const forkDigest = computeForkDigest(currentVersion, genesisValidatorsRoot);
+    try std.testing.expectEqual(4, forkDigest.len);
+}
+
+test "test computeForkDataRoot" {
+    const currentVersion = .{0} ** 4;
+    const genesisValidatorsRoot = .{0} ** 32;
+    const forkDataRoot = computeForkDataRoot(currentVersion, genesisValidatorsRoot);
+    try std.testing.expectEqual(32, forkDataRoot.len);
+}
diff --git a/src/consensus/types.zig b/src/consensus/types.zig
index 8462929..9d3b0b5 100644
--- a/src/consensus/types.zig
+++ b/src/consensus/types.zig
@@ -458,15 +458,6 @@ pub const BeaconState = union(primitives.ForkType) {
     }
 };
 
-// pub fn compute_fork_data_root(current_version: primitives.Version, genesis_validators_root: primitives.Root) primitives.Root {
-//     const fork_data = ForkData{
-//         .current_version = current_version,
-//         .genesis_validators_root = genesis_validators_root,
-//     };
-//
-//    return ssz.serialize_root(&fork_data);
-// }
-
 test "test Attestation" {
     const attestation = Attestation{
         .phase0 = phase0.Attestation{
diff --git a/src/root.zig b/src/root.zig
index 587ab48..b351774 100644
--- a/src/root.zig
+++ b/src/root.zig
@@ -14,6 +14,7 @@ pub const epoch_helper = @import("consensus/helpers/epoch.zig");
 pub const attestation_helper = @import("consensus/helpers/attestation.zig");
 pub const weak_subjectivity_helper = @import("consensus/helpers/weak_subjectivity.zig");
 pub const validator_helper = @import("consensus/helpers/validator.zig");
+pub const domain_helper = @import("consensus/helpers/domain.zig");
 
 test {
     @import("std").testing.refAllDeclsRecursive(@This());