diff --git a/.github/labeler.yml b/.github/labeler.yml
new file mode 100644
index 00000000..8cb24d34
--- /dev/null
+++ b/.github/labeler.yml
@@ -0,0 +1,42 @@
+# Add/remove 'critical' label if issue contains the words 'urgent' or 'critical'
+critical:
+  - "(critical|urgent)"
+
+cli:
+  - "/(cli|command)/i"
+
+daemon:
+  - "daemon"
+
+coordinator:
+  - "coordinator"
+
+runtime:
+  - "runtime"
+
+python:
+  - "python"
+
+c:
+  - "/\bc\b/i"
+
+c++:
+  - "cxx"
+
+rust:
+  - "rust"
+
+windows:
+  - "windows"
+
+macos:
+  - "macos"
+
+linux:
+  - "(linux|ubuntu)"
+
+bug:
+  - "bug"
+
+documentation:
+  - "(doc|documentation)"
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index ccf81303..260aa5b4 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -71,7 +71,7 @@ jobs:
     name: "CLI Test"
     strategy:
       matrix:
-        platform: [ubuntu-latest, macos-latest]
+        platform: [ubuntu-latest, macos-latest, windows-latest]
       fail-fast: false
     runs-on: ${{ matrix.platform }}
     steps:
diff --git a/.github/workflows/labeler.yml b/.github/workflows/labeler.yml
new file mode 100644
index 00000000..1fe3e190
--- /dev/null
+++ b/.github/workflows/labeler.yml
@@ -0,0 +1,15 @@
+name: "Issue Labeler"
+on:
+  issues:
+    types: [opened, edited]
+
+jobs:
+  triage:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: github/issue-labeler@v3.1 #May not be the latest version
+      with:
+        repo-token: "${{ github.token }}"
+        configuration-path: .github/labeler.yml
+        enable-versioned-regex: 0
+        include-title: 1
diff --git a/.github/workflows/pip-release.yml b/.github/workflows/pip-release.yml
index 35879de0..314b5de1 100644
--- a/.github/workflows/pip-release.yml
+++ b/.github/workflows/pip-release.yml
@@ -14,7 +14,7 @@ jobs:
 
     strategy:
       matrix:
-        platform: [ubuntu-latest, ubuntu-20.04]
+        platform: [ubuntu-latest, ubuntu-20.04, macos-latest, windows-latest]
         python-version: ["3.7"]
       fail-fast: false
     runs-on: ${{ matrix.platform }}
diff --git a/README.md b/README.md
index 52e00ce4..45aaf622 100644
--- a/README.md
+++ b/README.md
@@ -115,22 +115,55 @@ nodes:
 
 Composability as:
 - [x] `YAML` declarative programming
-- [x] polyglot:
-  - [x] Rust
-  - [x] C
-  - [x] C++
-  - [x] Python
 - [x] Isolated operators and custom nodes that can be reused.
+- [x] Hot Reloading for Python Operators
 
 Low latency as:
 - [x] written in  <i>...Cough...blazingly fast ...Cough...</i> Rust.
 - [x] PubSub communication with shared memory!
-- [ ] Zero-copy on read! 
+- [x] Zero-copy!
 
 Distributed as:
 - [ ] PubSub communication between machines with [`zenoh`](https://github.com/eclipse-zenoh/zenoh)
 - [x] Distributed telemetry with [`opentelemetry`](https://github.com/open-telemetry/opentelemetry-rust)
 
+## Support matrix
+
+### Programming Language API:
+
+- [x] Rust
+- [x] Python
+- [x] C
+- [x] C++
+- [ ] WebAssembly (Wished for)
+
+### OS:
+- [x] Linux Ubuntu (tested)
+- [x] MacOS (tested)
+- [x] Windows (tested)
+
+> Although, MacOS and Windows has a low priority for us now.
+
+### Platform:
+- [x] x86 (tested)
+- [ ] aarch64
+
+> Other platforms should also work althougth we haven't tested them yet.
+
+### Data Format
+- [x] Bytes
+- [x] Arrow Array (Uint8) for Python
+- [ ] Arrow Array (Uint16, Int32, ...) (Planned feature)
+- [ ] Arrow Map (Wished feature)
+
+### Local Communication
+- [x] TCP
+- [x] Shared Memory
+
+### Remote Communication
+- [x] TCP
+- [ ] Zenoh
+
 ---
 
 
diff --git a/binaries/cli/src/attach.rs b/binaries/cli/src/attach.rs
index f3e36d8f..a1e1bbc0 100644
--- a/binaries/cli/src/attach.rs
+++ b/binaries/cli/src/attach.rs
@@ -11,13 +11,11 @@ use std::{path::PathBuf, sync::mpsc, time::Duration};
 use tracing::{error, info};
 use uuid::Uuid;
 
-use crate::control_connection;
-
 pub fn attach_dataflow(
     dataflow: Descriptor,
     dataflow_path: PathBuf,
     dataflow_id: Uuid,
-    session: &mut Option<Box<TcpRequestReplyConnection>>,
+    session: &mut TcpRequestReplyConnection,
     hot_reload: bool,
 ) -> Result<(), eyre::ErrReport> {
     let (tx, rx) = mpsc::sync_channel(2);
@@ -70,7 +68,7 @@ pub fn attach_dataflow(
                     if let Some((dataflow_id, node_id, operator_id)) = node_path_lookup.get(&path) {
                         watcher_tx
                             .send(ControlRequest::Reload {
-                                dataflow_id: dataflow_id.clone(),
+                                dataflow_id: *dataflow_id,
                                 node_id: node_id.clone(),
                                 operator_id: operator_id.clone(),
                             })
@@ -123,7 +121,7 @@ pub fn attach_dataflow(
             Ok(reload_event) => reload_event,
         };
 
-        let reply_raw = control_connection(session)?
+        let reply_raw = session
             .request(&serde_json::to_vec(&control_request)?)
             .wrap_err("failed to send request message to coordinator")?;
         let result: ControlRequestReply =
diff --git a/binaries/cli/src/check.rs b/binaries/cli/src/check.rs
index a364630f..4b77eb13 100644
--- a/binaries/cli/src/check.rs
+++ b/binaries/cli/src/check.rs
@@ -1,4 +1,5 @@
-use crate::control_connection;
+use crate::connect_to_coordinator;
+use communication_layer_request_reply::TcpRequestReplyConnection;
 use dora_core::topics::{ControlRequest, ControlRequestReply};
 use eyre::{bail, Context};
 use std::io::Write;
@@ -16,19 +17,30 @@ pub fn check_environment() -> eyre::Result<()> {
 
     // check whether coordinator is running
     write!(stdout, "Dora Coordinator: ")?;
-    if coordinator_running()? {
-        let _ = stdout.set_color(ColorSpec::new().set_fg(Some(Color::Green)));
-        writeln!(stdout, "ok")?;
-    } else {
-        let _ = stdout.set_color(ColorSpec::new().set_fg(Some(Color::Red)));
-        writeln!(stdout, "not running")?;
-        error_occured = true;
-    }
+    let mut session = match connect_to_coordinator() {
+        Ok(session) => {
+            let _ = stdout.set_color(ColorSpec::new().set_fg(Some(Color::Green)));
+            writeln!(stdout, "ok")?;
+            Some(session)
+        }
+        Err(_) => {
+            let _ = stdout.set_color(ColorSpec::new().set_fg(Some(Color::Red)));
+            writeln!(stdout, "not running")?;
+            error_occured = true;
+            None
+        }
+    };
+
     let _ = stdout.reset();
 
     // check whether daemon is running
     write!(stdout, "Dora Daemon: ")?;
-    if daemon_running()? {
+    if session
+        .as_deref_mut()
+        .map(daemon_running)
+        .transpose()?
+        .unwrap_or(false)
+    {
         let _ = stdout.set_color(ColorSpec::new().set_fg(Some(Color::Green)));
         writeln!(stdout, "ok")?;
     } else {
@@ -47,30 +59,16 @@ pub fn check_environment() -> eyre::Result<()> {
     Ok(())
 }
 
-pub fn coordinator_running() -> Result<bool, eyre::ErrReport> {
-    let mut control_session = None;
-    let connected = control_connection(&mut control_session).is_ok();
-    Ok(connected)
-}
-
-pub fn daemon_running() -> Result<bool, eyre::ErrReport> {
-    let mut control_session = None;
-    let running = match control_connection(&mut control_session) {
-        Ok(connection) => {
-            let reply_raw = connection
-                .request(&serde_json::to_vec(&ControlRequest::DaemonConnected).unwrap())
-                .wrap_err("failed to send DaemonConnected message")?;
+pub fn daemon_running(session: &mut TcpRequestReplyConnection) -> Result<bool, eyre::ErrReport> {
+    let reply_raw = session
+        .request(&serde_json::to_vec(&ControlRequest::DaemonConnected).unwrap())
+        .wrap_err("failed to send DaemonConnected message")?;
 
-            let reply = serde_json::from_slice(&reply_raw).wrap_err("failed to parse reply")?;
-            match reply {
-                ControlRequestReply::DaemonConnected(running) => running,
-                other => bail!("unexpected reply to daemon connection check: {other:?}"),
-            }
-        }
-        Err(_) => {
-            // coordinator is not running
-            false
-        }
+    let reply = serde_json::from_slice(&reply_raw).wrap_err("failed to parse reply")?;
+    let running = match reply {
+        ControlRequestReply::DaemonConnected(running) => running,
+        other => bail!("unexpected reply to daemon connection check: {other:?}"),
     };
+
     Ok(running)
 }
diff --git a/binaries/cli/src/main.rs b/binaries/cli/src/main.rs
index 13552802..6c7daf04 100644
--- a/binaries/cli/src/main.rs
+++ b/binaries/cli/src/main.rs
@@ -117,13 +117,18 @@ enum Lang {
     Cxx,
 }
 
-fn main() -> eyre::Result<()> {
+fn main() {
+    if let Err(err) = run() {
+        eprintln!("{err:#}");
+        std::process::exit(1);
+    }
+}
+
+fn run() -> eyre::Result<()> {
     #[cfg(feature = "tracing")]
     set_up_tracing("dora-cli").context("failed to set up tracing subscriber")?;
     let args = Args::parse();
 
-    let mut session = None;
-
     match args.command {
         Command::Check { dataflow } => match dataflow {
             Some(dataflow) => {
@@ -178,26 +183,41 @@ fn main() -> eyre::Result<()> {
             dataflow_descriptor
                 .check(&working_dir)
                 .wrap_err("Could not validate yaml")?;
-            let dataflow_id =
-                start_dataflow(dataflow_descriptor.clone(), name, working_dir, &mut session)?;
+            let mut session =
+                connect_to_coordinator().wrap_err("failed to connect to dora coordinator")?;
+            let dataflow_id = start_dataflow(
+                dataflow_descriptor.clone(),
+                name,
+                working_dir,
+                &mut *session,
+            )?;
 
             if attach {
                 attach_dataflow(
                     dataflow_descriptor,
                     dataflow,
                     dataflow_id,
-                    &mut session,
+                    &mut *session,
                     hot_reload,
                 )?
             }
         }
-        Command::List => list(&mut session)?,
-        Command::Stop { uuid, name } => match (uuid, name) {
-            (Some(uuid), _) => stop_dataflow(uuid, &mut session)?,
-            (None, Some(name)) => stop_dataflow_by_name(name, &mut session)?,
-            (None, None) => stop_dataflow_interactive(&mut session)?,
+        Command::List => match connect_to_coordinator() {
+            Ok(mut session) => list(&mut *session)?,
+            Err(_) => {
+                bail!("No dora coordinator seems to be running.");
+            }
         },
-        Command::Destroy { config } => up::destroy(config.as_deref(), &mut session)?,
+        Command::Stop { uuid, name } => {
+            let mut session =
+                connect_to_coordinator().wrap_err("could not connect to dora coordinator")?;
+            match (uuid, name) {
+                (Some(uuid), _) => stop_dataflow(uuid, &mut *session)?,
+                (None, Some(name)) => stop_dataflow_by_name(name, &mut *session)?,
+                (None, None) => stop_dataflow_interactive(&mut *session)?,
+            }
+        }
+        Command::Destroy { config } => up::destroy(config.as_deref())?,
     }
 
     Ok(())
@@ -207,9 +227,9 @@ fn start_dataflow(
     dataflow: Descriptor,
     name: Option<String>,
     local_working_dir: PathBuf,
-    session: &mut Option<Box<TcpRequestReplyConnection>>,
+    session: &mut TcpRequestReplyConnection,
 ) -> Result<Uuid, eyre::ErrReport> {
-    let reply_raw = control_connection(session)?
+    let reply_raw = session
         .request(
             &serde_json::to_vec(&ControlRequest::Start {
                 dataflow,
@@ -232,9 +252,7 @@ fn start_dataflow(
     }
 }
 
-fn stop_dataflow_interactive(
-    session: &mut Option<Box<TcpRequestReplyConnection>>,
-) -> eyre::Result<()> {
+fn stop_dataflow_interactive(session: &mut TcpRequestReplyConnection) -> eyre::Result<()> {
     let uuids = query_running_dataflows(session).wrap_err("failed to query running dataflows")?;
     if uuids.is_empty() {
         eprintln!("No dataflows are running");
@@ -248,9 +266,9 @@ fn stop_dataflow_interactive(
 
 fn stop_dataflow(
     uuid: Uuid,
-    session: &mut Option<Box<TcpRequestReplyConnection>>,
+    session: &mut TcpRequestReplyConnection,
 ) -> Result<(), eyre::ErrReport> {
-    let reply_raw = control_connection(session)?
+    let reply_raw = session
         .request(
             &serde_json::to_vec(&ControlRequest::Stop {
                 dataflow_uuid: uuid,
@@ -269,9 +287,9 @@ fn stop_dataflow(
 
 fn stop_dataflow_by_name(
     name: String,
-    session: &mut Option<Box<TcpRequestReplyConnection>>,
+    session: &mut TcpRequestReplyConnection,
 ) -> Result<(), eyre::ErrReport> {
-    let reply_raw = control_connection(session)?
+    let reply_raw = session
         .request(&serde_json::to_vec(&ControlRequest::StopByName { name }).unwrap())
         .wrap_err("failed to send dataflow stop_by_name message")?;
     let result: ControlRequestReply =
@@ -283,7 +301,7 @@ fn stop_dataflow_by_name(
     }
 }
 
-fn list(session: &mut Option<Box<TcpRequestReplyConnection>>) -> Result<(), eyre::ErrReport> {
+fn list(session: &mut TcpRequestReplyConnection) -> Result<(), eyre::ErrReport> {
     let ids = query_running_dataflows(session)?;
 
     if ids.is_empty() {
@@ -299,9 +317,9 @@ fn list(session: &mut Option<Box<TcpRequestReplyConnection>>) -> Result<(), eyre
 }
 
 fn query_running_dataflows(
-    session: &mut Option<Box<TcpRequestReplyConnection>>,
+    session: &mut TcpRequestReplyConnection,
 ) -> Result<Vec<DataflowId>, eyre::ErrReport> {
-    let reply_raw = control_connection(session)?
+    let reply_raw = session
         .request(&serde_json::to_vec(&ControlRequest::List).unwrap())
         .wrap_err("failed to send list message")?;
     let reply: ControlRequestReply =
@@ -315,11 +333,6 @@ fn query_running_dataflows(
     Ok(ids)
 }
 
-fn control_connection(
-    session: &mut Option<Box<TcpRequestReplyConnection>>,
-) -> eyre::Result<&mut Box<TcpRequestReplyConnection>> {
-    Ok(match session {
-        Some(session) => session,
-        None => session.insert(TcpLayer::new().connect(control_socket_addr())?),
-    })
+fn connect_to_coordinator() -> std::io::Result<Box<TcpRequestReplyConnection>> {
+    TcpLayer::new().connect(control_socket_addr())
 }
diff --git a/binaries/cli/src/up.rs b/binaries/cli/src/up.rs
index 54cd6b5f..7d551a74 100644
--- a/binaries/cli/src/up.rs
+++ b/binaries/cli/src/up.rs
@@ -1,8 +1,4 @@
-use crate::{
-    check::{coordinator_running, daemon_running},
-    control_connection,
-};
-use communication_layer_request_reply::TcpRequestReplyConnection;
+use crate::{check::daemon_running, connect_to_coordinator};
 use dora_core::topics::ControlRequest;
 use eyre::Context;
 use std::{fs, path::Path, process::Command, time::Duration};
@@ -17,34 +13,44 @@ pub(crate) fn up(
 ) -> eyre::Result<()> {
     let UpConfig {} = parse_dora_config(config_path)?;
 
-    if !coordinator_running()? {
-        start_coordinator(coordinator).wrap_err("failed to start dora-coordinator")?;
-        // sleep a bit until the coordinator accepts connections
-        while !coordinator_running()? {
-            std::thread::sleep(Duration::from_millis(50));
+    let mut session = match connect_to_coordinator() {
+        Ok(session) => session,
+        Err(_) => {
+            start_coordinator(coordinator).wrap_err("failed to start dora-coordinator")?;
+
+            loop {
+                match connect_to_coordinator() {
+                    Ok(session) => break session,
+                    Err(_) => {
+                        // sleep a bit until the coordinator accepts connections
+                        std::thread::sleep(Duration::from_millis(50));
+                    }
+                }
+            }
         }
-    }
-    if !daemon_running()? {
+    };
+
+    if !daemon_running(&mut *session)? {
         start_daemon(daemon).wrap_err("failed to start dora-daemon")?;
     }
 
     Ok(())
 }
 
-pub(crate) fn destroy(
-    config_path: Option<&Path>,
-    session: &mut Option<Box<TcpRequestReplyConnection>>,
-) -> Result<(), eyre::ErrReport> {
+pub(crate) fn destroy(config_path: Option<&Path>) -> Result<(), eyre::ErrReport> {
     let UpConfig {} = parse_dora_config(config_path)?;
 
-    if coordinator_running()? {
-        // send destroy command to dora-coordinator
-        control_connection(session)?
-            .request(&serde_json::to_vec(&ControlRequest::Destroy).unwrap())
-            .wrap_err("failed to send destroy message")?;
-        println!("Send destroy command to dora-coordinator");
-    } else {
-        eprintln!("The dora-coordinator is not running");
+    match connect_to_coordinator() {
+        Ok(mut session) => {
+            // send destroy command to dora-coordinator
+            session
+                .request(&serde_json::to_vec(&ControlRequest::Destroy).unwrap())
+                .wrap_err("failed to send destroy message")?;
+            println!("Send destroy command to dora-coordinator");
+        }
+        Err(_) => {
+            eprintln!("Could not connect to dora-coordinator");
+        }
     }
 
     Ok(())
diff --git a/binaries/daemon/src/spawn.rs b/binaries/daemon/src/spawn.rs
index a46f655e..15581412 100644
--- a/binaries/daemon/src/spawn.rs
+++ b/binaries/daemon/src/spawn.rs
@@ -110,7 +110,10 @@ pub async fn spawn_node(
             let mut command = if has_python_operator && !has_other_operator {
                 // Use python to spawn runtime if there is a python operator
                 let mut command = tokio::process::Command::new("python3");
-                command.args(["-c", "import dora; dora.start_runtime()"]);
+                command.args([
+                    "-c",
+                    format!("import dora; dora.start_runtime() # {}", node.id).as_str(),
+                ]);
                 command
             } else if !has_python_operator && has_other_operator {
                 let mut cmd = tokio::process::Command::new(
diff --git a/binaries/runtime/src/operator/python.rs b/binaries/runtime/src/operator/python.rs
index b94001a5..3414c959 100644
--- a/binaries/runtime/src/operator/python.rs
+++ b/binaries/runtime/src/operator/python.rs
@@ -25,7 +25,7 @@ use tracing::{error, field, span, warn};
 fn traceback(err: pyo3::PyErr) -> eyre::Report {
     let traceback = Python::with_gil(|py| err.traceback(py).and_then(|t| t.format().ok()));
     if let Some(traceback) = traceback {
-        eyre::eyre!("{err}{traceback}")
+        eyre::eyre!("{traceback}\n{err}")
     } else {
         eyre::eyre!("{err}")
     }
diff --git a/libraries/extensions/telemetry/tracing/src/lib.rs b/libraries/extensions/telemetry/tracing/src/lib.rs
index 4d069e55..75c10783 100644
--- a/libraries/extensions/telemetry/tracing/src/lib.rs
+++ b/libraries/extensions/telemetry/tracing/src/lib.rs
@@ -4,6 +4,7 @@
 //! able to serialize and deserialize context that has been sent via the middleware.
 
 use eyre::Context as EyreContext;
+use tracing::metadata::LevelFilter;
 use tracing_subscriber::{prelude::__tracing_subscriber_SubscriberExt, EnvFilter, Layer};
 
 use eyre::ContextCompat;
@@ -12,7 +13,7 @@ pub mod telemetry;
 
 pub fn set_up_tracing(name: &str) -> eyre::Result<()> {
     // Filter log using `RUST_LOG`. More useful for CLI.
-    let filter = EnvFilter::from_default_env();
+    let filter = EnvFilter::from_default_env().add_directive(LevelFilter::WARN.into());
     let stdout_log = tracing_subscriber::fmt::layer()
         .pretty()
         .with_filter(filter);