rename cluster to swarm everywhere!

14 files changed, 162 insertions, 177 deletions

diff --git a/src/api/peers.rs b/src/api/peers.rs
index 5308eb9..d60e7b3 100644
--- a/src/api/peers.rs
+++ b/src/api/peers.rs
@@ -47,7 +47,7 @@ impl From<Epoch> for EpochInfo {
 #[serde(rename_all = "camelCase")]
 pub(crate) struct PeerStatus {
     public_key: String,
-    validated_cluster: Option<String>,
+    validated_swarm: Option<String>,
     status: PeerLivenessStatus,
     handshake_complete: bool,
     last_seen_secs_ago: Option<u64>,
@@ -112,9 +112,9 @@ pub(crate) async fn list_peers(
 
         peers.push(PeerStatus {
             public_key,
-            validated_cluster: match &ps.membership {
+            validated_swarm: match &ps.membership {
                 PeerMembership::Unknown => None,
-                PeerMembership::Member { cluster_id } => Some(cluster_id.clone()),
+                PeerMembership::Member { swarm_id } => Some(swarm_id.clone()),
             },
             status,
             handshake_complete: ps.hello_state == HelloState::Established,
@@ -144,7 +144,7 @@ pub(crate) async fn list_peers(
         ("force" = Option<bool>, Query, description = "Also forget a peer that is currently alive; it returns on its next message")
     ),
     responses(
-        (status = 204, description = "Cluster-wide forget recorded"),
+        (status = 204, description = "Swarm-wide forget recorded"),
         (status = 400, description = "Not a public key, or the local node's own key"),
         (status = 409, description = "Peer is alive; pass force=true"),
         (status = 503, description = "Node is not ready")
@@ -183,7 +183,7 @@ pub(crate) async fn delete_peer(
         .map_err(|e| store_status(e, "Failed to write forget record"))?;
 
     if state.peer_states.write().await.remove(&peer).is_some() {
-        warn!(peer = %peer, "Peer forgotten cluster-wide by operator");
+        warn!(peer = %peer, "Peer forgotten swarm-wide by operator");
     }
 
     Ok(StatusCode::NO_CONTENT)
diff --git a/src/document/replica.rs b/src/document/replica.rs
index ff3af4c..af807ea 100644
--- a/src/document/replica.rs
+++ b/src/document/replica.rs
@@ -11,7 +11,7 @@ use std::ops::{Deref, DerefMut};
 
 use automerge::AutoCommit;
 
-/// One generation of the cluster document.
+/// One generation of the swarm document.
 ///
 /// * `generation` orders epochs: every remake increments it, so a node can tell
 ///   whether a peer is behind or ahead.
@@ -36,7 +36,7 @@ pub enum EpochRelation {
 }
 
 impl Epoch {
-    /// Clusters that have never been compacted.
+    /// Swarms that have never been compacted.
     pub const GENESIS: Epoch = Epoch {
         generation: 0,
         id: [0; 32],
diff --git a/src/main.rs b/src/main.rs
index d9d24f3..ef9bf54 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -149,7 +149,7 @@ async fn main() -> Result<()> {
         doc: Arc::new(RwLock::new(Replica::new(initial_epoch, AutoCommit::new()))),
         epoch_tx,
         lifecycle: Arc::new(RwLock::new(NodeLifecycle::Joining {
-            discovered_cluster_id: None,
+            discovered_swarm_id: None,
         })),
         peer_states: Arc::new(RwLock::new(HashMap::new())),
         transport: Arc::new(FirewallTransport::new(
@@ -194,15 +194,15 @@ async fn main() -> Result<()> {
     trace!("Peer worker task spawned");
 
     // Switches to committed epochs and catches up with newer ones. Starts before
-    // bootstrapping: a node joining a compacted cluster can only finish its initial sync
+    // bootstrapping: a node joining a compacted swarm can only finish its initial sync
     // after fetching the current epoch from a peer.
     tokio::spawn(remake::run_worker(state.clone()));
     trace!("Remake worker task spawned");
 
     tokio::select! {
-        joined = bootstrap::bootstrap(&state, &seeds) => joined.context("Joining cluster")?,
+        joined = bootstrap::bootstrap(&state, &seeds) => joined.context("Joining swarm")?,
         _ = stopped(stop.clone()) => {
-            info!("Stopped while joining the cluster");
+            info!("Stopped while joining the swarm");
             return Ok(());
         }
     }
@@ -213,7 +213,7 @@ async fn main() -> Result<()> {
     tokio::spawn(async move { sync::run_change_publisher(publisher_state).await });
 
     info!(
-        cluster_id = ?state.cluster_id().await,
+        swarm_id = ?state.swarm_id().await,
         ready = state.is_ready().await,
         "Bootstrap completed"
     );
diff --git a/src/remake/api.rs b/src/remake/api.rs
index 7f62b48..fbd5f54 100644
--- a/src/remake/api.rs
+++ b/src/remake/api.rs
@@ -4,7 +4,7 @@
 //!   /admin/compaction` is a shortcut, kept from before). The receiving
 //!   node becomes its coordinator. `202` with the report, or with `?wait=true` the final
 //!   report once decided. A dropped request does not abort anything. `?force=true`
-//!   accepts a `settleSecs` below the dormancy threshold (tests, single-site clusters).
+//!   accepts a `settleSecs` below the dormancy threshold (tests, single-site swarms).
 //! * `GET /admin/remakes` lists all remakes.
 //! * `GET /admin/remakes/{id}` reports one; `?wait=true` long-polls until decided
 //!   (bounded by the proposal's own expiry).
@@ -22,7 +22,7 @@
 //!    "settleSecs": 480, "switchDelaySecs": 60 }`
 //!
 //! `?force=true` accepts `settleSecs` below the dormancy threshold and `switchDelaySecs`
-//! below one keepalive interval: for tests and debugging, not for real clusters.
+//! below one keepalive interval: for tests and debugging, not for real swarms.
 //!
 //! `kind` is `compact` (no spec) or `replace`, whose spec is
 //! `{ "document": {…store root…}, "rules": [{"from": "a", "to": "b"}, {"from": "c", "drop": true}] }`
diff --git a/src/remake/catchup.rs b/src/remake/catchup.rs
index c8878cc..4aa66e7 100644
--- a/src/remake/catchup.rs
+++ b/src/remake/catchup.rs
@@ -11,7 +11,7 @@
 //!    exactly like a new node joining;
 //! 3. once caught up with a peer, checks that the history starts with the epoch's
 //!    snapshot change;
-//! 4. decides about its own changes the cluster never saw (none, for a new node):
+//! 4. decides about its own changes the swarm never saw (none, for a new node):
 //!    * the metadata of the epoch that followed the node's own records which changes
 //!      went into it (per-actor clock); the rest are this node's missing changes;
 //!    * within that epoch's replay window they are replayed (state per path, as in a
@@ -374,7 +374,7 @@ fn prepare(mut copy: AutoCommit, mut old: AutoCommit, previous: Epoch, target: E
         (None, _) => Plan::Quarantine {
             paths,
             reason: format!(
-                "the metadata of the epoch after {previous} is missing, so it is unknown which of {} local changes the cluster has",
+                "the metadata of the epoch after {previous} is missing, so it is unknown which of {} local changes the swarm has",
                 missing.own
             ),
         },
@@ -386,7 +386,7 @@ fn prepare(mut copy: AutoCommit, mut old: AutoCommit, previous: Epoch, target: E
                 Plan::Quarantine {
                     paths,
                     reason: format!(
-                        "{} local changes are outside the replay window ({gap} epochs behind, cluster moved on {}s ago)",
+                        "{} local changes are outside the replay window ({gap} epochs behind, swarm moved on {}s ago)",
                         missing.own,
                         away_ms / 1000
                     ),
@@ -448,7 +448,7 @@ mod tests {
     use automerge::{transaction::Transactable, ActorId, ROOT};
     use serde_json::{json, Value as JsonValue};
 
-    /// An old-epoch document with one own change after the base, and the cluster's
+    /// An old-epoch document with one own change after the base, and the swarm's
     /// document of the next epoch (snapshot plus one foreign change).
     fn scenario(policy: &JsonValue) -> (AutoCommit, AutoCommit, Epoch) {
         let mut old = AutoCommit::new().with_actor(ActorId::from(&b"late-node"[..]));
@@ -472,19 +472,19 @@ mod tests {
         .unwrap();
         let target = snapshot.epoch;
 
-        let mut cluster = snapshot.doc.with_actor(ActorId::from(&b"cluster-node"[..]));
-        cluster.put(ROOT, "theirs", 1_i64).unwrap();
-        cluster.commit();
+        let mut swarm = snapshot.doc.with_actor(ActorId::from(&b"swarm-node"[..]));
+        swarm.put(ROOT, "theirs", 1_i64).unwrap();
+        swarm.commit();
 
         old.put(ROOT, "mine", 1_i64).unwrap();
         old.commit();
-        (old, cluster, target)
+        (old, swarm, target)
     }
 
     #[test]
     fn replays_within_the_window() {
-        let (old, cluster, target) = scenario(&json!({}));
-        match prepare(cluster, old, Epoch::GENESIS, target) {
+        let (old, swarm, target) = scenario(&json!({}));
+        match prepare(swarm, old, Epoch::GENESIS, target) {
             Prepared::Ready {
                 plan: Plan::Replay(paths, _),
                 own_missing,
@@ -499,8 +499,8 @@ mod tests {
 
     #[test]
     fn quarantines_outside_the_window() {
-        let (old, cluster, target) = scenario(&json!({ "replayWindow": { "epochs": 0 } }));
-        match prepare(cluster, old, Epoch::GENESIS, target) {
+        let (old, swarm, target) = scenario(&json!({ "replayWindow": { "epochs": 0 } }));
+        match prepare(swarm, old, Epoch::GENESIS, target) {
             Prepared::Ready {
                 plan: Plan::Quarantine { paths, .. },
                 ..
@@ -511,9 +511,9 @@ mod tests {
 
     #[test]
     fn new_node_has_nothing_to_replay() {
-        let (_, cluster, target) = scenario(&json!({}));
+        let (_, swarm, target) = scenario(&json!({}));
         assert!(matches!(
-            prepare(cluster, AutoCommit::new(), Epoch::GENESIS, target),
+            prepare(swarm, AutoCommit::new(), Epoch::GENESIS, target),
             Prepared::Ready {
                 plan: Plan::Nothing,
                 had_history: false,
diff --git a/src/remake/coordinator.rs b/src/remake/coordinator.rs
index b84b0a9..d1b3397 100644
--- a/src/remake/coordinator.rs
+++ b/src/remake/coordinator.rs
@@ -1,4 +1,4 @@
-//! The coordinator: the node that received the proposal watches the cluster during the
+//! The coordinator: the node that received the proposal watches the swarm during the
 //! settle period and then writes the decision.
 //!
 //! It aborts if, at any point before deciding:
diff --git a/src/remake/mod.rs b/src/remake/mod.rs
index 3cfaf0b..ff3c9c3 100644
--- a/src/remake/mod.rs
+++ b/src/remake/mod.rs
@@ -1,4 +1,4 @@
-//! Remakes: coordinated moves of the whole cluster to a new document, a new epoch.
+//! Remakes: coordinated moves of the whole swarm to a new document, a new epoch.
 //! Compaction is one: the new document has the old one's content without its history.
 //!
 //! * `kind`: what differs between kinds of remake (building the new document, and
@@ -66,7 +66,7 @@ pub(crate) trait Host: Clone + Send + Sync + 'static {
     /// Known (not forgotten) peers.
     fn peer_summaries(&self) -> impl Future<Output = Vec<PeerSummary>> + Send;
 
-    /// Stops serving requests (back to `Joining`, keeping the cluster ID), as while a
+    /// Stops serving requests (back to `Joining`, keeping the swarm ID), as while a
     /// rejoin syncs a fresh document. Returns whether the node was serving.
     fn suspend(&self) -> impl Future<Output = bool> + Send;
 
diff --git a/src/remake/snapshot.rs b/src/remake/snapshot.rs
index 507d8ac..bd99854 100644
--- a/src/remake/snapshot.rs
+++ b/src/remake/snapshot.rs
@@ -139,7 +139,7 @@ pub(crate) struct EpochMetadata {
     /// Highest sequence number per actor of `previous` contained in the snapshot.
     pub(crate) clock: BTreeMap<String, u64>,
     pub(crate) policy: Policy,
-    /// When the remake was proposed (unix ms): the point the cluster moved on.
+    /// When the remake was proposed (unix ms): the point the swarm moved on.
     pub(crate) proposed_at: u64,
     /// The remake kind and its translation input, for writes made before the epoch.
     pub(crate) kind: String,
@@ -206,7 +206,7 @@ fn parse_metadata(doc: &AutoCommit, generation: u64) -> Result<EpochMetadata, St
 /// the same generation. Returns the metadata.
 ///
 /// This does not prove the snapshot's content matches the old epoch; the hash commits
-/// to it, and the peer is a cluster member trusted as much as for ordinary sync.
+/// to it, and the peer is a swarm member trusted as much as for ordinary sync.
 pub(crate) fn verify_document(doc: &mut AutoCommit, epoch: Epoch) -> Result<EpochMetadata, String> {
     let root = ChangeHash(epoch.id);
     let Some(change) = doc.get_change_by_hash(&root) else {
@@ -653,14 +653,14 @@ mod tests {
         let policy = json!({});
         let mut snap = build(&mut late, &params(&base, &policy)).unwrap();
 
-        // Meanwhile the cluster moved on in the new epoch.
-        let mut cluster = snap
+        // Meanwhile the swarm moved on in the new epoch.
+        let mut swarm = snap
             .doc
             .fork()
-            .with_actor(ActorId::from(&b"cluster-node"[..]));
-        cluster.put(ROOT, "new", 1_i64).unwrap();
-        cluster.commit();
-        let bytes = cluster.save();
+            .with_actor(ActorId::from(&b"swarm-node"[..]));
+        swarm.put(ROOT, "new", 1_i64).unwrap();
+        swarm.commit();
+        let bytes = swarm.save();
 
         late.put(ROOT, "mine", "late").unwrap();
         late.commit();
diff --git a/src/state.rs b/src/state.rs
index 81a3e6a..736f55b 100644
--- a/src/state.rs
+++ b/src/state.rs
@@ -20,13 +20,9 @@ use crate::transport::firewall::Firewall;
 
 #[derive(Debug, Clone, PartialEq, Eq)]
 pub(crate) enum NodeLifecycle {
-    // TODO maybe rename discovered_cluster_id to cluster_id if that doesn't impair readability.
-    Joining {
-        discovered_cluster_id: Option<String>,
-    },
-    Ready {
-        cluster_id: String,
-    },
+    // TODO maybe rename discovered_swarm_id to swarm_id if that doesn't impair readability.
+    Joining { discovered_swarm_id: Option<String> },
+    Ready { swarm_id: String },
 }
 
 #[derive(Debug, Clone, Default, PartialEq, Eq)]
@@ -34,7 +30,7 @@ pub(crate) enum PeerMembership {
     #[default]
     Unknown,
     Member {
-        cluster_id: String,
+        swarm_id: String,
     },
 }
 
@@ -75,7 +71,7 @@ pub(crate) struct PeerState {
     pub(crate) sync_state: sync::State,
     pub(crate) hello_state: HelloState,
 
-    /// The peer sent HELLO; we still owe it a HELLO_REPLY (e.g. we had no cluster ID yet,
+    /// The peer sent HELLO; we still owe it a HELLO_REPLY (e.g. we had no swarm ID yet,
     /// or sending failed).
     pub(crate) reply_owed: bool,
 
@@ -302,7 +298,7 @@ impl PeerState {
     }
 
     /// Heard from recently. A returning node counts as alive from its first message,
-    /// before the handshake finishes, so a cluster-wide forget can't make it flap.
+    /// before the handshake finishes, so a swarm-wide forget can't make it flap.
     pub(crate) fn is_alive(&self, timing: &Timing, now: Instant) -> bool {
         self.liveness == Liveness::Active
             && self
@@ -324,9 +320,9 @@ impl Timing {
     //  Environment                                 | Keepalive | Notes
     //  --------------------------------------------+-----------+------------------------------------------------------------
     //  Test harness                                | 1-2 s     | Dormancy after about 4–8 s and healing within seconds keep tests short.
-    //  LAN or small cluster (up to ~50 nodes)      | 15-30 s   | Under 3.5 messages/s per node at 50 nodes and 30 s. Current setting.
+    //  LAN or small swarm (up to ~50 nodes)      | 15-30 s   | Under 3.5 messages/s per node at 50 nodes and 30 s. Current setting.
     //  WAN, mobile or metered links, or 100+ nodes | 60-120 s  | At 100 nodes and 30 s it’s about 6–7 messages/s per node. Fine, but rarely worth it on battery or metered links.
-    //  Several hundred nodes or more               | -         | The full mesh becomes the problem in itself, not the interval. Message counts grow O(N²) across the cluster, which calls for partial views (SWIM-style random probing and syncing with a subset of peers).
+    //  Several hundred nodes or more               | -         | The full mesh becomes the problem in itself, not the interval. Message counts grow O(N²) across the swarm, which calls for partial views (SWIM-style random probing and syncing with a subset of peers).
     pub(crate) fn from_keepalive(keepalive: Duration) -> Self {
         Self {
             keepalive,
@@ -348,8 +344,8 @@ pub(crate) struct AppState {
 
     pub(crate) lifecycle: Arc<RwLock<NodeLifecycle>>,
 
-    // Serializes cluster-ID establishment, peer membership, and readiness transitions.
-    //[concurrent]cluster_validation: Arc<Mutex<()>>,
+    // Serializes swarm-ID establishment, peer membership, and readiness transitions.
+    //[concurrent]swarm_validation: Arc<Mutex<()>>,
     pub(crate) peer_states: Arc<RwLock<HashMap<String, Arc<Mutex<PeerState>>>>>,
     pub(crate) transport: Arc<dyn transport::Transport>,
     pub(crate) firewall: Arc<Firewall>,
@@ -388,94 +384,86 @@ impl AppState {
         matches!(*self.lifecycle.read().await, NodeLifecycle::Ready { .. })
     }
 
-    pub(crate) async fn cluster_id(&self) -> Option<String> {
+    pub(crate) async fn swarm_id(&self) -> Option<String> {
         match &*self.lifecycle.read().await {
-            NodeLifecycle::Ready { cluster_id } => Some(cluster_id.clone()),
+            NodeLifecycle::Ready { swarm_id } => Some(swarm_id.clone()),
             NodeLifecycle::Joining {
-                discovered_cluster_id,
-            } => discovered_cluster_id.clone(),
+                discovered_swarm_id,
+            } => discovered_swarm_id.clone(),
         }
     }
 
-    // Record the expected cluster without making the node Ready. Bootstrap owns readiness.
-    pub(crate) async fn set_expected_cluster_id(&self, cluster_id: String) -> Result<()> {
-        //[concurrent]let _guard = self.cluster_validation.lock().await;
+    // Record the expected swarm without making the node Ready. Bootstrap owns readiness.
+    pub(crate) async fn set_expected_swarm_id(&self, swarm_id: String) -> Result<()> {
+        //[concurrent]let _guard = self.swarm_validation.lock().await;
         let mut lifecycle = self.lifecycle.write().await;
         match &*lifecycle {
             NodeLifecycle::Joining {
-                discovered_cluster_id: Some(existing),
-            } if existing != &cluster_id => {
+                discovered_swarm_id: Some(existing),
+            } if existing != &swarm_id => {
                 bail!(
-                    "Conflicting expected cluster IDs: expected {}, received {}",
+                    "Conflicting expected swarm IDs: expected {}, received {}",
                     existing,
-                    cluster_id
+                    swarm_id
                 );
             }
             NodeLifecycle::Joining {
-                discovered_cluster_id: None,
+                discovered_swarm_id: None,
             } => {
                 let old_lifecycle = lifecycle.clone();
                 *lifecycle = NodeLifecycle::Joining {
-                    discovered_cluster_id: Some(cluster_id),
+                    discovered_swarm_id: Some(swarm_id),
                 };
                 debug!("Node transitioned from {old_lifecycle:?} {lifecycle:?}");
                 Ok(())
             }
             NodeLifecycle::Joining {
-                discovered_cluster_id: Some(_),
+                discovered_swarm_id: Some(_),
             } => {
                 warn!("Node already Joining with the same identity");
                 Ok(())
             }
-            NodeLifecycle::Ready {
-                cluster_id: existing,
-            } if existing == &cluster_id => {
+            NodeLifecycle::Ready { swarm_id: existing } if existing == &swarm_id => {
                 warn!("Node already Ready with the same identity");
                 Ok(())
             }
-            NodeLifecycle::Ready {
-                cluster_id: existing,
-            } => {
+            NodeLifecycle::Ready { swarm_id: existing } => {
                 bail!(
-                    "Cannot change established cluster ID: existing {}, received {}",
+                    "Cannot change established swarm ID: existing {}, received {}",
                     existing,
-                    cluster_id
+                    swarm_id
                 );
             }
         }
     }
 
     // Only bootstrap should call this, after validating document metadata.
-    pub(crate) async fn mark_ready(&self, cluster_id: String) -> Result<()> {
-        //[concurrent]let _guard = self.cluster_validation.lock().await;
+    pub(crate) async fn mark_ready(&self, swarm_id: String) -> Result<()> {
+        //[concurrent]let _guard = self.swarm_validation.lock().await;
         let mut lifecycle = self.lifecycle.write().await;
         match &*lifecycle {
             NodeLifecycle::Joining {
-                discovered_cluster_id: Some(expected),
-            } if expected != &cluster_id => {
+                discovered_swarm_id: Some(expected),
+            } if expected != &swarm_id => {
                 bail!(
-                    "Cannot mark node ready: expected cluster {}, received {}",
+                    "Cannot mark node ready: expected swarm {}, received {}",
                     expected,
-                    cluster_id
+                    swarm_id
                 );
             }
             NodeLifecycle::Joining { .. } => {
                 let old_lifecycle = lifecycle.clone();
-                *lifecycle = NodeLifecycle::Ready { cluster_id };
+                *lifecycle = NodeLifecycle::Ready { swarm_id };
                 debug!("Node transitioned from {old_lifecycle:?} {lifecycle:?}");
             }
-            NodeLifecycle::Ready {
-                cluster_id: existing,
-            } if existing == &cluster_id => {
+            NodeLifecycle::Ready { swarm_id: existing } if existing == &swarm_id => {
                 debug!("Node already ready with the same identity");
             }
-            NodeLifecycle::Ready {
-                cluster_id: existing,
-            } => {
+            NodeLifecycle::Ready { swarm_id: existing } => {
                 bail!(
-                    "Cannot change established cluster ID: existing {}, received {}",
+                    "Cannot change established swarm ID: existing {}, received {}",
                     existing,
-                    cluster_id
+                    swarm_id
                 );
             }
         }
@@ -774,13 +762,13 @@ impl Host for AppState {
         let state = self.clone();
         async move {
             let mut lifecycle = state.lifecycle.write().await;
-            let NodeLifecycle::Ready { cluster_id } = &*lifecycle else {
+            let NodeLifecycle::Ready { swarm_id } = &*lifecycle else {
                 return false;
             };
-            let cluster_id = cluster_id.clone();
-            debug!(cluster_id = %cluster_id, "Node suspended (rejoining)");
+            let swarm_id = swarm_id.clone();
+            debug!(swarm_id = %swarm_id, "Node suspended (rejoining)");
             *lifecycle = NodeLifecycle::Joining {
-                discovered_cluster_id: Some(cluster_id),
+                discovered_swarm_id: Some(swarm_id),
             };
             true
         }
@@ -791,12 +779,12 @@ impl Host for AppState {
         async move {
             let mut lifecycle = state.lifecycle.write().await;
             if let NodeLifecycle::Joining {
-                discovered_cluster_id: Some(cluster_id),
+                discovered_swarm_id: Some(swarm_id),
             } = &*lifecycle
             {
-                let cluster_id = cluster_id.clone();
-                debug!(cluster_id = %cluster_id, "Node resumed");
-                *lifecycle = NodeLifecycle::Ready { cluster_id };
+                let swarm_id = swarm_id.clone();
+                debug!(swarm_id = %swarm_id, "Node resumed");
+                *lifecycle = NodeLifecycle::Ready { swarm_id };
             }
         }
     }
diff --git a/src/swarm/bootstrap.rs b/src/swarm/bootstrap.rs
index 47fadfa..b279cb1 100644
--- a/src/swarm/bootstrap.rs
+++ b/src/swarm/bootstrap.rs
@@ -1,4 +1,4 @@
-//! Joining a cluster (or creating one as the genesis node).
+//! Joining a swarm (or creating one as the genesis node).
 
 use std::sync::atomic::Ordering;
 use std::time::Duration;
@@ -23,7 +23,7 @@ pub(crate) async fn bootstrap(state: &AppState, seeds: &[String]) -> Result<()>
 
     info!(
         timeout_seconds = BOOTSTRAP_TIMEOUT.as_secs(),
-        "Joining existing cluster"
+        "Joining existing swarm"
     );
 
     let mut peers = Vec::new();
@@ -51,12 +51,12 @@ pub(crate) async fn bootstrap(state: &AppState, seeds: &[String]) -> Result<()>
 
     let deadline = tokio::time::Instant::now() + BOOTSTRAP_TIMEOUT;
     loop {
-        if let Some(cluster_id) = state.cluster_id().await {
-            // A node joining a compacted cluster rejoins the newer epoch first; it is
+        if let Some(swarm_id) = state.swarm_id().await {
+            // A node joining a compacted swarm rejoins the newer epoch first; it is
             // ready only once that rejoin verified the epoch.
             if state.initial_sync_done.load(Ordering::Acquire) && !state.remake.is_rejoining() {
-                state.mark_ready(cluster_id.clone()).await?;
-                info!(cluster_id = %cluster_id, "Node is ready");
+                state.mark_ready(swarm_id.clone()).await?;
+                info!(swarm_id = %swarm_id, "Node is ready");
                 return Ok(());
             }
         }
@@ -68,22 +68,22 @@ pub(crate) async fn bootstrap(state: &AppState, seeds: &[String]) -> Result<()>
 
             for (peer, peer_state_mutex) in &peer_states {
                 let peer_state = peer_state_mutex.lock().await;
-                let validated_cluster = match &peer_state.membership {
+                let validated_swarm = match &peer_state.membership {
                     PeerMembership::Unknown => None,
-                    PeerMembership::Member { cluster_id } => Some(cluster_id.as_str()),
+                    PeerMembership::Member { swarm_id } => Some(swarm_id.as_str()),
                 };
                 peer_diagnostics.push(format!(
-                    "{peer}: validated_cluster={:?}, epoch={:?}, pending_inbound_sync={}",
-                    validated_cluster,
+                    "{peer}: validated_swarm={:?}, epoch={:?}, pending_inbound_sync={}",
+                    validated_swarm,
                     peer_state.epoch,
                     peer_state.pending_inbound_sync.len()
                 ))
             }
-            let local_cluster = state.cluster_id().await;
+            let local_swarm = state.swarm_id().await;
             let local_epoch = state.local_epoch();
             let initial_sync_done = state.initial_sync_done.load(Ordering::Acquire);
             error!(
-                local_cluster = ?local_cluster,
+                local_swarm = ?local_swarm,
                 local_epoch = %local_epoch,
                 initial_sync_done,
                 peers = %peer_diagnostics.join("; "),
@@ -91,9 +91,9 @@ pub(crate) async fn bootstrap(state: &AppState, seeds: &[String]) -> Result<()>
                 "Bootstrap timed out"
             );
             bail!(
-                "Bootstrap timed out after {:?}; local_cluster={:?}; local_epoch={}; initial_sync_done={}; peers=[{}]. Refusing to create a genesis document.",
+                "Bootstrap timed out after {:?}; local_swarm={:?}; local_epoch={}; initial_sync_done={}; peers=[{}]. Refusing to create a genesis document.",
                 BOOTSTRAP_TIMEOUT,
-                local_cluster,
+                local_swarm,
                 local_epoch,
                 initial_sync_done,
                 peer_diagnostics.join("; ")
diff --git a/src/swarm/peer.rs b/src/swarm/peer.rs
index 6184427..53a4731 100644
--- a/src/swarm/peer.rs
+++ b/src/swarm/peer.rs
@@ -1,5 +1,5 @@
 //! Peers: handshake (HELLO / HELLO_REPLY), liveness and keepalives, self-healing,
-//! cluster-wide forget records, and dispatch of inbound messages.
+//! swarm-wide forget records, and dispatch of inbound messages.
 
 use std::sync::Arc;
 use std::time::Duration;
@@ -70,7 +70,7 @@ async fn apply_forget_records(state: &AppState) {
         if alive {
             cancel.push(pk);
         } else if state.peer_states.write().await.remove(&pk).is_some() {
-            info!(peer = %pk, "Forgetting peer per cluster-wide record");
+            info!(peer = %pk, "Forgetting peer per swarm-wide record");
         }
     }
 
@@ -84,7 +84,7 @@ async fn apply_forget_records(state: &AppState) {
         .mutate_doc(move |doc| {
             for pk in &cancel {
                 match store::delete_path(&mut *doc, &forgotten_path(pk), false) {
-                    Ok(()) => info!(peer = %pk, "Peer is alive; cancelling cluster-wide forget"),
+                    Ok(()) => info!(peer = %pk, "Peer is alive; cancelling swarm-wide forget"),
                     Err(StoreError::NotFound) => {}
                     Err(error) => {
                         warn!(peer = %pk, error = %error, "Failed to cancel forget record")
@@ -267,10 +267,10 @@ async fn ensure_handshake(state: &AppState, peer: &str) {
     }
 }
 
-/// Sends a HELLO_REPLY if one is owed and our cluster ID is known.
+/// Sends a HELLO_REPLY if one is owed and our swarm ID is known.
 /// Otherwise it stays owed and the peer worker tries again.
 async fn send_owed_hello_reply(state: &AppState, peer: &str) {
-    if state.cluster_id().await.is_none() {
+    if state.swarm_id().await.is_none() {
         return;
     }
 
@@ -297,10 +297,10 @@ async fn flush_owed_hello_replies(state: &AppState) {
 }
 
 async fn send_hello_reply(state: &AppState, peer: &str) -> Result<()> {
-    let cluster_id = state
-        .cluster_id()
+    let swarm_id = state
+        .swarm_id()
         .await
-        .ok_or_else(|| anyhow!("Cannot send HELLO_REPLY without an established cluster ID"))?;
+        .ok_or_else(|| anyhow!("Cannot send HELLO_REPLY without an established swarm ID"))?;
 
     let candidates: Vec<(String, Arc<Mutex<PeerState>>)> = state
         .peer_states
@@ -322,7 +322,7 @@ async fn send_hello_reply(state: &AppState, peer: &str) -> Result<()> {
     }
 
     let reply = transport::HelloReply {
-        cluster_id,
+        swarm_id,
         peers,
         epoch: state.local_epoch(),
     };
@@ -441,16 +441,16 @@ pub(crate) async fn run_peer_worker(state: AppState) {
 async fn establish_peer(
     state: &AppState,
     peer: &str,
-    cluster_id: String,
+    swarm_id: String,
 ) -> Result<Vec<transport::SyncEnvelope>> {
-    let expected_cluster = state.cluster_id().await;
+    let expected_swarm = state.swarm_id().await;
 
-    if let Some(expected) = &expected_cluster {
-        if expected != &cluster_id {
+    if let Some(expected) = &expected_swarm {
+        if expected != &swarm_id {
             bail!(
-                "Incompatible cluster at {peer}: expected {}, received {}",
+                "Incompatible swarm at {peer}: expected {}, received {}",
                 expected,
-                cluster_id
+                swarm_id
             );
         }
     }
@@ -458,27 +458,24 @@ async fn establish_peer(
     let peer_state_mutex = state.get_or_create_peer_state(peer).await;
     let mut peer_state = peer_state_mutex.lock().await;
 
-    if let PeerMembership::Member {
-        cluster_id: existing,
-    } = &peer_state.membership
-    {
-        if existing != &cluster_id {
+    if let PeerMembership::Member { swarm_id: existing } = &peer_state.membership {
+        if existing != &swarm_id {
             bail!(
-                "Peer {peer} changed cluster identity from {} to {}",
+                "Peer {peer} changed swarm identity from {} to {}",
                 existing,
-                cluster_id
+                swarm_id
             );
         }
     }
 
     // Lock order: peer mutex -> lifecycle.
-    if expected_cluster.is_none() {
-        state.set_expected_cluster_id(cluster_id.clone()).await?;
+    if expected_swarm.is_none() {
+        state.set_expected_swarm_id(swarm_id.clone()).await?;
     }
 
     if matches!(peer_state.membership, PeerMembership::Unknown) {
         peer_state.membership = PeerMembership::Member {
-            cluster_id: cluster_id.clone(),
+            swarm_id: swarm_id.clone(),
         };
     }
 
@@ -492,17 +489,17 @@ async fn establish_peer(
 
     let pending = std::mem::take(&mut peer_state.pending_inbound_sync);
 
-    info!(peer = %peer, cluster_id = %cluster_id, pending_messages = pending.len(), "Peer membership established");
+    info!(peer = %peer, swarm_id = %swarm_id, pending_messages = pending.len(), "Peer membership established");
     Ok(pending)
 }
 
 #[instrument(skip(state), fields(peer = %peer))]
-pub(crate) async fn peer_cluster(state: &AppState, peer: &str) -> Option<String> {
+pub(crate) async fn peer_swarm(state: &AppState, peer: &str) -> Option<String> {
     let peer_state_mutex = state.get_peer_state(peer).await?;
     let peer_state = peer_state_mutex.lock().await;
     match &peer_state.membership {
         PeerMembership::Unknown => None,
-        PeerMembership::Member { cluster_id } => Some(cluster_id.clone()),
+        PeerMembership::Member { swarm_id } => Some(swarm_id.clone()),
     }
 }
 
@@ -607,7 +604,7 @@ pub(crate) async fn handle_message(
                 peer_state.reply_owed = true;
             }
 
-            // Sends now if we know our cluster ID; otherwise stays owed.
+            // Sends now if we know our swarm ID; otherwise stays owed.
             send_owed_hello_reply(state, &peer).await;
 
             // Our own HELLO goes out regardless of whether the reply could be sent.
@@ -621,11 +618,11 @@ pub(crate) async fn handle_message(
                 .send(SyncEvent::PeerNeedsSync(peer.clone()));
         }
         transport::ParsedMessage::HelloReply(reply) => {
-            let pending = establish_peer(state, &peer, reply.cluster_id.clone()).await?;
+            let pending = establish_peer(state, &peer, reply.swarm_id.clone()).await?;
 
             discover_peers(state, &peer, &reply.peers).await;
 
-            // Our cluster ID may have just become known: pay any replies we owe.
+            // Our swarm ID may have just become known: pay any replies we owe.
             flush_owed_hello_replies(state).await;
 
             if !pending.is_empty() {
@@ -657,7 +654,7 @@ pub(crate) async fn handle_message(
             handle_sync(state, &peer, envelope).await?;
         }
         transport::ParsedMessage::Ping(remote) => {
-            if reactivated || peer_cluster(state, &peer).await.is_none() {
+            if reactivated || peer_swarm(state, &peer).await.is_none() {
                 ensure_handshake(state, &peer).await;
             }
             let local = local_keepalive(state).await;
@@ -671,7 +668,7 @@ pub(crate) async fn handle_message(
             }
         }
         transport::ParsedMessage::Pong(remote) => {
-            if reactivated || peer_cluster(state, &peer).await.is_none() {
+            if reactivated || peer_swarm(state, &peer).await.is_none() {
                 ensure_handshake(state, &peer).await;
             }
             let local = local_keepalive(state).await;
diff --git a/src/swarm/sync.rs b/src/swarm/sync.rs
index 04d5b15..0c7148e 100644
--- a/src/swarm/sync.rs
+++ b/src/swarm/sync.rs
@@ -13,7 +13,7 @@ use tokio::time::Instant;
 use tracing::{debug, info, trace, warn};
 
 use crate::state::{AppState, Liveness, PeerMembership, PeerState, PendingOutbound};
-use crate::swarm::peer::{peer_cluster, send_hello_once};
+use crate::swarm::peer::{peer_swarm, send_hello_once};
 use crate::transport::{self, ParsedMessage};
 
 const INITIAL_SYNC_RETRY: Duration = Duration::from_millis(500);
@@ -40,7 +40,7 @@ async fn deliver_sync_to_peer(state: &AppState, peer: &str, retry_delivery: bool
         return Ok(());
     };
 
-    let validated_cluster = {
+    let validated_swarm = {
         let peer_state = peer_state_mutex.lock().await;
 
         if matches!(peer_state.liveness, Liveness::Dormant { .. }) {
@@ -60,17 +60,17 @@ async fn deliver_sync_to_peer(state: &AppState, peer: &str, retry_delivery: bool
 
         match &peer_state.membership {
             PeerMembership::Unknown => return Ok(()),
-            PeerMembership::Member { cluster_id } => cluster_id.clone(),
+            PeerMembership::Member { swarm_id } => swarm_id.clone(),
         }
     };
 
-    let cluster_id = state
-        .cluster_id()
+    let swarm_id = state
+        .swarm_id()
         .await
-        .ok_or_else(|| anyhow!("Cannot sync without an established cluster ID"))?;
+        .ok_or_else(|| anyhow!("Cannot sync without an established swarm ID"))?;
 
-    if validated_cluster != cluster_id {
-        bail!("Peer {peer} belongs to a different cluster");
+    if validated_swarm != swarm_id {
+        bail!("Peer {peer} belongs to a different swarm");
     }
 
     let existing = {
@@ -127,7 +127,7 @@ async fn deliver_sync_to_peer(state: &AppState, peer: &str, retry_delivery: bool
                         return Ok(None);
                     };
                     let envelope = transport::SyncEnvelope {
-                        cluster_id,
+                        swarm_id,
                         epoch,
                         message,
                     };
@@ -221,7 +221,7 @@ pub(crate) async fn handle_sync(
             PeerMembership::Unknown => {
                 let duplicate = peer_state.pending_inbound_sync.iter().any(|pending| {
                     pending.message == envelope.message
-                        && pending.cluster_id == envelope.cluster_id
+                        && pending.swarm_id == envelope.swarm_id
                         && pending.epoch == envelope.epoch
                 });
                 if !duplicate {
@@ -236,10 +236,10 @@ pub(crate) async fn handle_sync(
                 }
                 true
             }
-            PeerMembership::Member { cluster_id } if cluster_id != &envelope.cluster_id => {
+            PeerMembership::Member { swarm_id } if swarm_id != &envelope.swarm_id => {
                 bail!(
-                    "Sync cluster mismatch for peer {peer}: validated_cluster={cluster_id}, envelope_cluster={}",
-                    envelope.cluster_id
+                    "Sync swarm mismatch for peer {peer}: validated_swarm={swarm_id}, envelope_swarm={}",
+                    envelope.swarm_id
                 );
             }
             PeerMembership::Member { .. } => false,
@@ -255,15 +255,15 @@ pub(crate) async fn handle_sync(
         return Ok(());
     }
 
-    let expected_cluster = state
-        .cluster_id()
+    let expected_swarm = state
+        .swarm_id()
         .await
-        .ok_or_else(|| anyhow!("Missing expected cluster ID after peer membership"))?;
-    if envelope.cluster_id != expected_cluster {
+        .ok_or_else(|| anyhow!("Missing expected swarm ID after peer membership"))?;
+    if envelope.swarm_id != expected_swarm {
         bail!(
-            "Incompatible cluster from {peer}: expected {}, received {}",
-            expected_cluster,
-            envelope.cluster_id
+            "Incompatible swarm from {peer}: expected {}, received {}",
+            expected_swarm,
+            envelope.swarm_id
         );
     }
 
@@ -462,7 +462,7 @@ pub(crate) async fn run_sync_worker(state: AppState, mut rx: mpsc::UnboundedRece
             };
 
             for peer in peer_keys {
-                if peer_cluster(&state, &peer).await.is_some() {
+                if peer_swarm(&state, &peer).await.is_some() {
                     dirty_peers.insert(peer);
                 }
             }
diff --git a/src/transport/mod.rs b/src/transport/mod.rs
index 6accf81..0afb5ee 100644
--- a/src/transport/mod.rs
+++ b/src/transport/mod.rs
@@ -47,14 +47,14 @@ pub struct HelloRequest {
 
 #[derive(Debug, Clone)]
 pub struct HelloReply {
-    pub cluster_id: String,
+    pub swarm_id: String,
     pub peers: Vec<String>,
     pub epoch: Epoch,
 }
 
 #[derive(Debug, Clone)]
 pub struct SyncEnvelope {
-    pub cluster_id: String,
+    pub swarm_id: String,
     /// Epoch of the document the message was generated from.
     pub epoch: Epoch,
     pub message: Message,
diff --git a/src/transport/mycelium.rs b/src/transport/mycelium.rs
index a8a0e10..194f998 100644
--- a/src/transport/mycelium.rs
+++ b/src/transport/mycelium.rs
@@ -203,7 +203,7 @@ pub async fn fetch_admin_info(rest_url: &Url) -> Result<MyceliumAdminInfo> {
 }
 
 #[derive(Debug, Clone)]
-pub struct ClusterNodeConfig {
+pub struct MyceliumNodeConfig {
     pub tcp_port: u16,
     pub api_port: u16,
     pub rpc_port: u16,
@@ -213,7 +213,7 @@ pub struct ClusterNodeConfig {
 
 pub struct SupervisedMycelium {
     child: Child,
-    pub config: ClusterNodeConfig,
+    pub config: MyceliumNodeConfig,
     _key_file_handle: Option<File>,
     _net_key_file_handle: Option<File>,
     key_file_path: PathBuf,
@@ -251,7 +251,7 @@ impl SupervisedMycelium {
             p => p,
         };
 
-        let config = ClusterNodeConfig {
+        let config = MyceliumNodeConfig {
             tcp_port,
             api_port,
             rpc_port,
@@ -856,7 +856,7 @@ pub struct HelloRequestShadow {
 #[derive(Serialize, Deserialize)]
 pub struct HelloReplyShadow<'a> {
     // Cow allows zero-copy references when saving, but creates an owned String when loading
-    pub cluster_id: Cow<'a, str>,
+    pub swarm_id: Cow<'a, str>,
     #[serde(default)]
     pub peers: Vec<String>,
     #[serde(default)]
@@ -865,7 +865,7 @@ pub struct HelloReplyShadow<'a> {
 
 #[derive(Serialize, Deserialize)]
 pub struct SyncEnvelopeShadow<'a> {
-    pub cluster_id: Cow<'a, str>,
+    pub swarm_id: Cow<'a, str>,
     #[serde(with = "automerge_msg_codec")]
     pub message: automerge::sync::Message,
     #[serde(default)]
@@ -917,7 +917,7 @@ pub fn bytes_to_hello_request(bytes: &[u8]) -> Result<HelloRequest, TransportErr
 // --- HelloReply ---
 pub fn hello_reply_to_bytes(msg: &HelloReply) -> Result<Vec<u8>, rmp_serde::encode::Error> {
     let shadow = HelloReplyShadow {
-        cluster_id: Cow::Borrowed(&msg.cluster_id),
+        swarm_id: Cow::Borrowed(&msg.swarm_id),
         peers: msg.peers.clone(), // Vec must be cloned for serialization wrapper matching
         epoch: epoch_to_shadow(&msg.epoch),
     };
@@ -926,7 +926,7 @@ pub fn hello_reply_to_bytes(msg: &HelloReply) -> Result<Vec<u8>, rmp_serde::enco
 pub fn bytes_to_hello_reply(bytes: &[u8]) -> Result<HelloReply, TransportError> {
     let shadow: HelloReplyShadow = rmp_serde::from_slice(bytes)?;
     Ok(HelloReply {
-        cluster_id: shadow.cluster_id.into_owned(),
+        swarm_id: shadow.swarm_id.into_owned(),
         peers: shadow.peers,
         epoch: epoch_from_shadow(shadow.epoch)?,
     })
@@ -935,7 +935,7 @@ pub fn bytes_to_hello_reply(bytes: &[u8]) -> Result<HelloReply, TransportError>
 // --- SyncEnvelope ---
 pub fn sync_envelope_to_bytes(msg: &SyncEnvelope) -> Result<Vec<u8>, rmp_serde::encode::Error> {
     let shadow = SyncEnvelopeShadow {
-        cluster_id: Cow::Borrowed(&msg.cluster_id),
+        swarm_id: Cow::Borrowed(&msg.swarm_id),
         message: msg.message.clone(), // Clone required by automerge_msg_codec ownership rules
         epoch: epoch_to_shadow(&msg.epoch),
     };
@@ -944,7 +944,7 @@ pub fn sync_envelope_to_bytes(msg: &SyncEnvelope) -> Result<Vec<u8>, rmp_serde::
 pub fn bytes_to_sync_envelope(bytes: &[u8]) -> Result<SyncEnvelope, TransportError> {
     let shadow: SyncEnvelopeShadow = rmp_serde::from_slice(bytes)?;
     Ok(SyncEnvelope {
-        cluster_id: shadow.cluster_id.into_owned(),
+        swarm_id: shadow.swarm_id.into_owned(),
         epoch: epoch_from_shadow(shadow.epoch)?,
         message: shadow.message,
     })