diff --git a/Cargo.lock b/Cargo.lock
index fce57023..29c22ed4 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -2940,7 +2940,7 @@ dependencies = [
 [[package]]
 name = "zenoh"
 version = "1.4.0"
-source = "git+https://github.com/eclipse-zenoh/zenoh.git?branch=main#249e4be7cb5f89a7914b3b3bac54c8213dcd209b"
+source = "git+https://github.com/eclipse-zenoh/zenoh.git?branch=main#ba0cae6c4294aec9f9306810785769ed28b726b0"
 dependencies = [
  "ahash",
  "arc-swap",
@@ -2989,7 +2989,7 @@ dependencies = [
 [[package]]
 name = "zenoh-buffers"
 version = "1.4.0"
-source = "git+https://github.com/eclipse-zenoh/zenoh.git?branch=main#249e4be7cb5f89a7914b3b3bac54c8213dcd209b"
+source = "git+https://github.com/eclipse-zenoh/zenoh.git?branch=main#ba0cae6c4294aec9f9306810785769ed28b726b0"
 dependencies = [
  "zenoh-collections",
 ]
@@ -2997,7 +2997,7 @@ dependencies = [
 [[package]]
 name = "zenoh-codec"
 version = "1.4.0"
-source = "git+https://github.com/eclipse-zenoh/zenoh.git?branch=main#249e4be7cb5f89a7914b3b3bac54c8213dcd209b"
+source = "git+https://github.com/eclipse-zenoh/zenoh.git?branch=main#ba0cae6c4294aec9f9306810785769ed28b726b0"
 dependencies = [
  "tracing",
  "uhlc",
@@ -3008,7 +3008,7 @@ dependencies = [
 [[package]]
 name = "zenoh-collections"
 version = "1.4.0"
-source = "git+https://github.com/eclipse-zenoh/zenoh.git?branch=main#249e4be7cb5f89a7914b3b3bac54c8213dcd209b"
+source = "git+https://github.com/eclipse-zenoh/zenoh.git?branch=main#ba0cae6c4294aec9f9306810785769ed28b726b0"
 dependencies = [
  "ahash",
 ]
@@ -3016,7 +3016,7 @@ dependencies = [
 [[package]]
 name = "zenoh-config"
 version = "1.4.0"
-source = "git+https://github.com/eclipse-zenoh/zenoh.git?branch=main#249e4be7cb5f89a7914b3b3bac54c8213dcd209b"
+source = "git+https://github.com/eclipse-zenoh/zenoh.git?branch=main#ba0cae6c4294aec9f9306810785769ed28b726b0"
 dependencies = [
  "json5",
  "nonempty-collections",
@@ -3040,7 +3040,7 @@ dependencies = [
 [[package]]
 name = "zenoh-core"
 version = "1.4.0"
-source = "git+https://github.com/eclipse-zenoh/zenoh.git?branch=main#249e4be7cb5f89a7914b3b3bac54c8213dcd209b"
+source = "git+https://github.com/eclipse-zenoh/zenoh.git?branch=main#ba0cae6c4294aec9f9306810785769ed28b726b0"
 dependencies = [
  "lazy_static",
  "tokio",
@@ -3051,7 +3051,7 @@ dependencies = [
 [[package]]
 name = "zenoh-crypto"
 version = "1.4.0"
-source = "git+https://github.com/eclipse-zenoh/zenoh.git?branch=main#249e4be7cb5f89a7914b3b3bac54c8213dcd209b"
+source = "git+https://github.com/eclipse-zenoh/zenoh.git?branch=main#ba0cae6c4294aec9f9306810785769ed28b726b0"
 dependencies = [
  "aes",
  "hmac",
@@ -3064,7 +3064,7 @@ dependencies = [
 [[package]]
 name = "zenoh-ext"
 version = "1.4.0"
-source = "git+https://github.com/eclipse-zenoh/zenoh.git?branch=main#249e4be7cb5f89a7914b3b3bac54c8213dcd209b"
+source = "git+https://github.com/eclipse-zenoh/zenoh.git?branch=main#ba0cae6c4294aec9f9306810785769ed28b726b0"
 dependencies = [
  "async-trait",
  "bincode",
@@ -3083,7 +3083,7 @@ dependencies = [
 [[package]]
 name = "zenoh-keyexpr"
 version = "1.4.0"
-source = "git+https://github.com/eclipse-zenoh/zenoh.git?branch=main#249e4be7cb5f89a7914b3b3bac54c8213dcd209b"
+source = "git+https://github.com/eclipse-zenoh/zenoh.git?branch=main#ba0cae6c4294aec9f9306810785769ed28b726b0"
 dependencies = [
  "getrandom",
  "hashbrown 0.14.5",
@@ -3098,7 +3098,7 @@ dependencies = [
 [[package]]
 name = "zenoh-link"
 version = "1.4.0"
-source = "git+https://github.com/eclipse-zenoh/zenoh.git?branch=main#249e4be7cb5f89a7914b3b3bac54c8213dcd209b"
+source = "git+https://github.com/eclipse-zenoh/zenoh.git?branch=main#ba0cae6c4294aec9f9306810785769ed28b726b0"
 dependencies = [
  "zenoh-config",
  "zenoh-link-commons",
@@ -3115,7 +3115,7 @@ dependencies = [
 [[package]]
 name = "zenoh-link-commons"
 version = "1.4.0"
-source = "git+https://github.com/eclipse-zenoh/zenoh.git?branch=main#249e4be7cb5f89a7914b3b3bac54c8213dcd209b"
+source = "git+https://github.com/eclipse-zenoh/zenoh.git?branch=main#ba0cae6c4294aec9f9306810785769ed28b726b0"
 dependencies = [
  "async-trait",
  "flume",
@@ -3140,7 +3140,7 @@ dependencies = [
 [[package]]
 name = "zenoh-link-quic"
 version = "1.4.0"
-source = "git+https://github.com/eclipse-zenoh/zenoh.git?branch=main#249e4be7cb5f89a7914b3b3bac54c8213dcd209b"
+source = "git+https://github.com/eclipse-zenoh/zenoh.git?branch=main#ba0cae6c4294aec9f9306810785769ed28b726b0"
 dependencies = [
  "async-trait",
  "base64 0.22.1",
@@ -3167,7 +3167,7 @@ dependencies = [
 [[package]]
 name = "zenoh-link-tcp"
 version = "1.4.0"
-source = "git+https://github.com/eclipse-zenoh/zenoh.git?branch=main#249e4be7cb5f89a7914b3b3bac54c8213dcd209b"
+source = "git+https://github.com/eclipse-zenoh/zenoh.git?branch=main#ba0cae6c4294aec9f9306810785769ed28b726b0"
 dependencies = [
  "async-trait",
  "socket2",
@@ -3184,7 +3184,7 @@ dependencies = [
 [[package]]
 name = "zenoh-link-tls"
 version = "1.4.0"
-source = "git+https://github.com/eclipse-zenoh/zenoh.git?branch=main#249e4be7cb5f89a7914b3b3bac54c8213dcd209b"
+source = "git+https://github.com/eclipse-zenoh/zenoh.git?branch=main#ba0cae6c4294aec9f9306810785769ed28b726b0"
 dependencies = [
  "async-trait",
  "base64 0.22.1",
@@ -3213,7 +3213,7 @@ dependencies = [
 [[package]]
 name = "zenoh-link-udp"
 version = "1.4.0"
-source = "git+https://github.com/eclipse-zenoh/zenoh.git?branch=main#249e4be7cb5f89a7914b3b3bac54c8213dcd209b"
+source = "git+https://github.com/eclipse-zenoh/zenoh.git?branch=main#ba0cae6c4294aec9f9306810785769ed28b726b0"
 dependencies = [
  "async-trait",
  "libc",
@@ -3234,7 +3234,7 @@ dependencies = [
 [[package]]
 name = "zenoh-link-unixsock_stream"
 version = "1.4.0"
-source = "git+https://github.com/eclipse-zenoh/zenoh.git?branch=main#249e4be7cb5f89a7914b3b3bac54c8213dcd209b"
+source = "git+https://github.com/eclipse-zenoh/zenoh.git?branch=main#ba0cae6c4294aec9f9306810785769ed28b726b0"
 dependencies = [
  "async-trait",
  "nix",
@@ -3252,7 +3252,7 @@ dependencies = [
 [[package]]
 name = "zenoh-link-ws"
 version = "1.4.0"
-source = "git+https://github.com/eclipse-zenoh/zenoh.git?branch=main#249e4be7cb5f89a7914b3b3bac54c8213dcd209b"
+source = "git+https://github.com/eclipse-zenoh/zenoh.git?branch=main#ba0cae6c4294aec9f9306810785769ed28b726b0"
 dependencies = [
  "async-trait",
  "futures-util",
@@ -3272,7 +3272,7 @@ dependencies = [
 [[package]]
 name = "zenoh-macros"
 version = "1.4.0"
-source = "git+https://github.com/eclipse-zenoh/zenoh.git?branch=main#249e4be7cb5f89a7914b3b3bac54c8213dcd209b"
+source = "git+https://github.com/eclipse-zenoh/zenoh.git?branch=main#ba0cae6c4294aec9f9306810785769ed28b726b0"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -3283,7 +3283,7 @@ dependencies = [
 [[package]]
 name = "zenoh-plugin-trait"
 version = "1.4.0"
-source = "git+https://github.com/eclipse-zenoh/zenoh.git?branch=main#249e4be7cb5f89a7914b3b3bac54c8213dcd209b"
+source = "git+https://github.com/eclipse-zenoh/zenoh.git?branch=main#ba0cae6c4294aec9f9306810785769ed28b726b0"
 dependencies = [
  "git-version",
  "libloading",
@@ -3299,7 +3299,7 @@ dependencies = [
 [[package]]
 name = "zenoh-protocol"
 version = "1.4.0"
-source = "git+https://github.com/eclipse-zenoh/zenoh.git?branch=main#249e4be7cb5f89a7914b3b3bac54c8213dcd209b"
+source = "git+https://github.com/eclipse-zenoh/zenoh.git?branch=main#ba0cae6c4294aec9f9306810785769ed28b726b0"
 dependencies = [
  "const_format",
  "rand",
@@ -3326,7 +3326,7 @@ dependencies = [
 [[package]]
 name = "zenoh-result"
 version = "1.4.0"
-source = "git+https://github.com/eclipse-zenoh/zenoh.git?branch=main#249e4be7cb5f89a7914b3b3bac54c8213dcd209b"
+source = "git+https://github.com/eclipse-zenoh/zenoh.git?branch=main#ba0cae6c4294aec9f9306810785769ed28b726b0"
 dependencies = [
  "anyhow",
 ]
@@ -3334,7 +3334,7 @@ dependencies = [
 [[package]]
 name = "zenoh-runtime"
 version = "1.4.0"
-source = "git+https://github.com/eclipse-zenoh/zenoh.git?branch=main#249e4be7cb5f89a7914b3b3bac54c8213dcd209b"
+source = "git+https://github.com/eclipse-zenoh/zenoh.git?branch=main#ba0cae6c4294aec9f9306810785769ed28b726b0"
 dependencies = [
  "lazy_static",
  "ron",
@@ -3348,7 +3348,7 @@ dependencies = [
 [[package]]
 name = "zenoh-sync"
 version = "1.4.0"
-source = "git+https://github.com/eclipse-zenoh/zenoh.git?branch=main#249e4be7cb5f89a7914b3b3bac54c8213dcd209b"
+source = "git+https://github.com/eclipse-zenoh/zenoh.git?branch=main#ba0cae6c4294aec9f9306810785769ed28b726b0"
 dependencies = [
  "arc-swap",
  "event-listener",
@@ -3362,7 +3362,7 @@ dependencies = [
 [[package]]
 name = "zenoh-task"
 version = "1.4.0"
-source = "git+https://github.com/eclipse-zenoh/zenoh.git?branch=main#249e4be7cb5f89a7914b3b3bac54c8213dcd209b"
+source = "git+https://github.com/eclipse-zenoh/zenoh.git?branch=main#ba0cae6c4294aec9f9306810785769ed28b726b0"
 dependencies = [
  "futures",
  "tokio",
@@ -3375,7 +3375,7 @@ dependencies = [
 [[package]]
 name = "zenoh-transport"
 version = "1.4.0"
-source = "git+https://github.com/eclipse-zenoh/zenoh.git?branch=main#249e4be7cb5f89a7914b3b3bac54c8213dcd209b"
+source = "git+https://github.com/eclipse-zenoh/zenoh.git?branch=main#ba0cae6c4294aec9f9306810785769ed28b726b0"
 dependencies = [
  "async-trait",
  "crossbeam-utils",
@@ -3408,7 +3408,7 @@ dependencies = [
 [[package]]
 name = "zenoh-util"
 version = "1.4.0"
-source = "git+https://github.com/eclipse-zenoh/zenoh.git?branch=main#249e4be7cb5f89a7914b3b3bac54c8213dcd209b"
+source = "git+https://github.com/eclipse-zenoh/zenoh.git?branch=main#ba0cae6c4294aec9f9306810785769ed28b726b0"
 dependencies = [
  "async-trait",
  "const_format",
diff --git a/src/macros.rs b/src/macros.rs
index cc94427f..5433291b 100644
--- a/src/macros.rs
+++ b/src/macros.rs
@@ -86,7 +86,7 @@ macro_rules! downcast_or_new {
 pub(crate) use downcast_or_new;
 
 macro_rules! enum_mapper {
-    ($($path:ident)::*: $repr:ty { $($variant:ident $(= $discriminator:literal)?),* $(,)? }) => {
+    ($($path:ident)::*: $repr:ty { $($variant:ident $(= $discriminator:literal)?,)* }) => {
         $crate::macros::enum_mapper!(@ $($path)::*, $($path)::*: $repr { $($variant $(= $discriminator)?,)* });
     };
     (@ $ty:ident::$($tt:ident)::*, $path:path: $repr:ty { $($variant:ident $(= $discriminator:literal)?,)* }) => {
diff --git a/src/qos.rs b/src/qos.rs
index 159c63e0..2b60e1bb 100644
--- a/src/qos.rs
+++ b/src/qos.rs
@@ -40,6 +40,7 @@ impl Priority {
 enum_mapper!(zenoh::qos::CongestionControl: u8 {
     Drop = 0,
     Block = 1,
+    BlockFirst = 2,
 });
 
 #[pymethods]
@@ -50,7 +51,7 @@ impl CongestionControl {
 
 enum_mapper!(zenoh::qos::Reliability: u8 {
     BestEffort,
-    Reliable
+    Reliable,
 });
 
 #[pymethods]
diff --git a/zenoh/__init__.pyi b/zenoh/__init__.pyi
index 676e0c9c..0d8f936f 100644
--- a/zenoh/__init__.pyi
+++ b/zenoh/__init__.pyi
@@ -57,6 +57,7 @@ class CongestionControl(Enum):
 
     DROP = auto()
     BLOCK = auto()
+    BLOCK_FIRST = _unstable(auto())
 
     DEFAULT = DROP