diff --git a/.github/workflows/rust-build.yml b/.github/workflows/rust-build.yml
index d28224ce..e61c2a52 100644
--- a/.github/workflows/rust-build.yml
+++ b/.github/workflows/rust-build.yml
@@ -47,3 +47,17 @@ jobs:
       - run: |
           cd gen/pb-rust
           cargo build --verbose
+
+  test:
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        toolchain:
+          - stable
+
+    steps:
+      - uses: actions/checkout@v3
+      - run: rustup update ${{ matrix.toolchain }} && rustup default ${{ matrix.toolchain }}
+      - run: |
+          cd gen/pb-rust
+          cargo test --tests
diff --git a/gen/pb-rust/tests/integration.rs b/gen/pb-rust/tests/integration.rs
index 48271bb7..6ef078f9 100644
--- a/gen/pb-rust/tests/integration.rs
+++ b/gen/pb-rust/tests/integration.rs
@@ -2,8 +2,7 @@ use pretty_assertions::{assert_eq, assert_ne};
 use serde_json;
 use sigstore_protobuf_specs::{
     Bundle, DevSigstoreBundleV1VerificationMaterial as VerificationMaterial,
-    DevSigstoreCommonV1HashOutput as HashOutput,
-    DevSigstoreCommonV1HashOutputAlgorithm as HashAlgorithm, DevSigstoreCommonV1LogId as LogId,
+    DevSigstoreCommonV1HashOutput as HashOutput, DevSigstoreCommonV1LogId as LogId,
     DevSigstoreCommonV1MessageSignature as MessageSignature,
     DevSigstoreCommonV1X509Certificate as X509Certificate,
     DevSigstoreCommonV1X509CertificateChain as X509CertificateChain,
@@ -75,7 +74,7 @@ fn bundle() {
             }),
             message_signature: Some(MessageSignature {
                 message_digest: Some(HashOutput{
-                    algorithm: Some(HashAlgorithm::Variant0(String::from("SHA2_256"))),
+                    algorithm: Some(String::from("SHA2_256")),
                     digest: Some(String::from("gC3WD/iDM4AvJYXnMEO9IcNBKF4Zkv5bMXVeHK3q4w4="))
                 }),
                 signature: Some(String::from("MGUCMQCOOJqTY6XWgB64izK2WVP07b0SG9M5WPCwKhfTPwMvtsgUi8KeRGwQkvvLYbKHdqUCMEbOXFG0NMqEQxWVb6rmGnexdADuGf6Jl8qAC8tn67p3QfVoXzMvFA61PzxwVwvb8g=="))
diff --git a/gen/pb-rust/tests/unit.rs b/gen/pb-rust/tests/unit.rs
index 6d523f54..f6346a4e 100644
--- a/gen/pb-rust/tests/unit.rs
+++ b/gen/pb-rust/tests/unit.rs
@@ -1,6 +1,5 @@
 use sigstore_protobuf_specs::{
     DevSigstoreCommonV1HashOutput as HashOutput,
-    DevSigstoreCommonV1HashOutputAlgorithm as HashAlgorithm,
     DevSigstoreCommonV1MessageSignature as MessageSignature,
 };
 
@@ -8,7 +7,7 @@ use sigstore_protobuf_specs::{
 #[test]
 fn primitives() {
     let hash_output = HashOutput {
-        algorithm: Some(HashAlgorithm::Variant0(String::from("SHA2_256"))),
+        algorithm: Some(String::from("SHA2_256")),
         digest: Some(String::from("gC3WD/iDM4AvJYXnMEO9IcNBKF4Zkv5bMXVeHK3q4w4=")),
     };
 
@@ -25,7 +24,7 @@ fn primitives() {
 fn nested() {
     let message_signature= MessageSignature {
         message_digest: Some(HashOutput {
-            algorithm: Some(HashAlgorithm::Variant0(String::from("SHA_256"))),
+            algorithm: Some(String::from("SHA_256")),
             digest: Some(String::from("gC3WD/iDM4AvJYXnMEO9IcNBKF4Zkv5bMXVeHK3q4w4=")),
         }),
         signature: Some(String::from("MGUCMQCOOJqTY6XWgB64izK2WVP07b0SG9M5WPCwKhfTPwMvtsgUi8KeRGwQkvvLYbKHdqUCMEbOXFG0NMqEQxWVb6rmGnexdADuGf6Jl8qAC8tn67p3QfVoXzMvFA61PzxwVwvb8g=="))