diff --git a/.github/CODEOWNERS b/.github/CODEOWNERS
index b77c7568..82804b9e 100644
--- a/.github/CODEOWNERS
+++ b/.github/CODEOWNERS
@@ -1,12 +1,10 @@
 CODEOWNERS @brunoffranca
 
 /node/actors/consensus/ @brunoffranca @moshababo
-/node/actors/executor/ @brunoffranca @pompon0 @slowli
 /node/actors/network/ @pompon0
 /node/actors/sync_blocks/ @slowli
 
 /node/libs/concurrency/ @pompon0
 /node/libs/crypto/ @brunoffranca
 /node/libs/protobuf/ @pompon0
-/node/libs/protobuf_build/ @pompon0
-/node/libs/storage/ @slowli
\ No newline at end of file
+/node/libs/protobuf_build/ @pompon0
\ No newline at end of file
diff --git a/node/libs/protobuf/src/lib.rs b/node/libs/protobuf/src/lib.rs
index 49958df5..2ad12b50 100644
--- a/node/libs/protobuf/src/lib.rs
+++ b/node/libs/protobuf/src/lib.rs
@@ -5,6 +5,8 @@
 pub mod build;
 pub mod proto;
 mod proto_fmt;
+pub mod repr;
+pub use repr::{read_required_repr, ProtoRepr};
 pub mod serde;
 mod std_conv;
 pub mod testonly;
diff --git a/node/libs/protobuf/src/repr.rs b/node/libs/protobuf/src/repr.rs
new file mode 100644
index 00000000..e8659715
--- /dev/null
+++ b/node/libs/protobuf/src/repr.rs
@@ -0,0 +1,33 @@
+//! Trait for defining proto conversion for external types.
+
+use crate::build::prost_reflect::ReflectMessage;
+use anyhow::Context as _;
+
+/// Trait reverse to `zksync_protobuf::ProtoFmt` for cases where
+/// you would like to specify a custom proto encoding for an externally defined type.
+pub trait ProtoRepr: ReflectMessage + Default {
+    /// The externally defined type associated with the proto Self.
+    type Type;
+    /// Converts proto Self to `Type`.
+    fn read(&self) -> anyhow::Result<Self::Type>;
+    /// Converts `Type` to proto Self.
+    fn build(this: &Self::Type) -> Self;
+}
+
+/// Parses a required proto field.
+pub fn read_required_repr<P: ProtoRepr>(field: &Option<P>) -> anyhow::Result<P::Type> {
+    field.as_ref().context("missing field")?.read()
+}
+
+/// Encodes a proto message.
+/// Currently it outputs a canonical encoding, but `decode` accepts
+/// non-canonical encoding as well.
+pub fn encode<P: ProtoRepr>(msg: &P::Type) -> Vec<u8> {
+    let msg = P::build(msg);
+    super::canonical_raw(&msg.encode_to_vec(), &msg.descriptor()).unwrap()
+}
+
+/// Decodes a proto message.
+pub fn decode<P: ProtoRepr>(bytes: &[u8]) -> anyhow::Result<P::Type> {
+    P::read(&P::decode(bytes)?)
+}
diff --git a/node/libs/protobuf/src/testonly/gen_value.rs b/node/libs/protobuf/src/testonly/gen_value.rs
new file mode 100644
index 00000000..4c091e37
--- /dev/null
+++ b/node/libs/protobuf/src/testonly/gen_value.rs
@@ -0,0 +1,27 @@
+//! Util types for generating random values in tests.
+
+use rand::Rng;
+
+/// Generator of random values.
+pub struct GenValue<'a, R: Rng> {
+    /// Underlying RNG.
+    pub rng: &'a mut R,
+    /// Generate values with only required fields.
+    pub required_only: bool,
+    /// Generate decimal fractions for f64
+    /// to avoid rounding errors of decimal encodings.
+    pub decimal_fractions: bool,
+}
+
+impl<'a, R: Rng> GenValue<'a, R> {
+    /// Generates a random value of type `C`.
+    pub fn gen<C: RandomValue>(&mut self) -> C {
+        C::sample(self)
+    }
+}
+
+/// Types that can be used to generate a random instance.
+pub trait RandomValue {
+    /// Generates a random value.
+    fn sample(g: &mut GenValue<impl Rng>) -> Self;
+}
diff --git a/node/libs/protobuf/src/testonly.rs b/node/libs/protobuf/src/testonly/mod.rs
similarity index 98%
rename from node/libs/protobuf/src/testonly.rs
rename to node/libs/protobuf/src/testonly/mod.rs
index bae47cf0..e86a6479 100644
--- a/node/libs/protobuf/src/testonly.rs
+++ b/node/libs/protobuf/src/testonly/mod.rs
@@ -1,5 +1,8 @@
 //! Testonly utilities.
+
+pub mod gen_value;
 use super::{canonical, canonical_raw, decode, encode, read_fields, ProtoFmt, Wire};
+pub use gen_value::*;
 use prost::Message as _;
 use prost_reflect::ReflectMessage as _;
 use rand::{