diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 5c09e2c..26e2d1e 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -14,6 +14,16 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
+      - name: Install build deps
+        # lance-encoding's build.rs invokes protoc to generate prost
+        # bindings. `protobuf-compiler` provides the `protoc` binary;
+        # `libprotobuf-dev` provides the well-known types (e.g.
+        # google/protobuf/empty.proto) under /usr/include/google/protobuf/
+        # that lance-encoding's .proto files import. Both are needed.
+        run: |
+          sudo apt-get update -qq
+          sudo apt-get install -y --no-install-recommends \
+            protobuf-compiler libprotobuf-dev
       - uses: dtolnay/rust-toolchain@stable
         with:
           components: clippy, rustfmt
diff --git a/omem-server/src/api/handlers/sharing.rs b/omem-server/src/api/handlers/sharing.rs
index cbb7c79..faa5225 100644
--- a/omem-server/src/api/handlers/sharing.rs
+++ b/omem-server/src/api/handlers/sharing.rs
@@ -512,32 +512,31 @@ pub async fn batch_share(
 
     use futures::stream::{self, StreamExt};
 
-    let results: Vec<(String, Result<Memory, OmemError>)> =
-        stream::iter(body.memory_ids.into_iter())
-            .map(|mem_id| {
-                let source_store = source_store.clone();
-                let target_store = target_store.clone();
-                let space_store = state.space_store.clone();
-                let target_space_id = target_space.id.clone();
-                let user_id = auth.tenant_id.clone();
-                let agent_id = agent_id.clone();
-                async move {
-                    let result = share_single(
-                        &source_store,
-                        &target_store,
-                        &space_store,
-                        &mem_id,
-                        &target_space_id,
-                        &user_id,
-                        &agent_id,
-                    )
-                    .await;
-                    (mem_id, result)
-                }
-            })
-            .buffer_unordered(10)
-            .collect()
-            .await;
+    let results: Vec<(String, Result<Memory, OmemError>)> = stream::iter(body.memory_ids)
+        .map(|mem_id| {
+            let source_store = source_store.clone();
+            let target_store = target_store.clone();
+            let space_store = state.space_store.clone();
+            let target_space_id = target_space.id.clone();
+            let user_id = auth.tenant_id.clone();
+            let agent_id = agent_id.clone();
+            async move {
+                let result = share_single(
+                    &source_store,
+                    &target_store,
+                    &space_store,
+                    &mem_id,
+                    &target_space_id,
+                    &user_id,
+                    &agent_id,
+                )
+                .await;
+                (mem_id, result)
+            }
+        })
+        .buffer_unordered(10)
+        .collect()
+        .await;
 
     let mut succeeded = Vec::new();
     let mut failed = Vec::new();
@@ -921,7 +920,7 @@ pub async fn share_all(
 
     use futures::stream::{self, StreamExt};
 
-    let results: Vec<(bool, bool)> = stream::iter(filtered_ids.into_iter())
+    let results: Vec<(bool, bool)> = stream::iter(filtered_ids)
         .map(|mem_id| {
             let source_store = source_store.clone();
             let target_store = target_store.clone();
@@ -1087,7 +1086,7 @@ pub async fn share_all_to_user(
 
     use futures::stream::{self, StreamExt};
 
-    let results: Vec<(bool, bool)> = stream::iter(filtered_ids.into_iter())
+    let results: Vec<(bool, bool)> = stream::iter(filtered_ids)
         .map(|mem_id| {
             let source_store = source_store.clone();
             let target_store = target_store.clone();
@@ -1260,7 +1259,7 @@ pub async fn org_publish(
 
         use futures::stream::{self, StreamExt};
 
-        let results: Vec<(bool, bool)> = stream::iter(memory_ids.clone().into_iter())
+        let results: Vec<(bool, bool)> = stream::iter(memory_ids.clone())
             .map(|mem_id| {
                 let source_store = source_store.clone();
                 let target_store = target_store.clone();
diff --git a/omem-server/src/api/handlers/stats.rs b/omem-server/src/api/handlers/stats.rs
index a994341..89f57ce 100644
--- a/omem-server/src/api/handlers/stats.rs
+++ b/omem-server/src/api/handlers/stats.rs
@@ -304,7 +304,7 @@ pub async fn get_tags(
         .into_iter()
         .filter(|(_, c)| *c >= params.min_count)
         .collect();
-    tags.sort_by(|a, b| b.1.cmp(&a.1));
+    tags.sort_by_key(|t| std::cmp::Reverse(t.1));
     let total_unique = tags.len();
     tags.truncate(params.limit);
 
@@ -554,7 +554,7 @@ pub async fn get_spaces_stats(
         }
 
         let mut top_categories: Vec<(String, usize)> = category_counts.into_iter().collect();
-        top_categories.sort_by(|a, b| b.1.cmp(&a.1));
+        top_categories.sort_by_key(|c| std::cmp::Reverse(c.1));
         top_categories.truncate(3);
 
         space_stats.push(serde_json::json!({
@@ -758,7 +758,7 @@ pub async fn get_agents_stats(
         }
 
         let mut top_categories: Vec<(String, usize)> = category_counts.into_iter().collect();
-        top_categories.sort_by(|a, b| b.1.cmp(&a.1));
+        top_categories.sort_by_key(|c| std::cmp::Reverse(c.1));
         top_categories.truncate(3);
 
         let share_count = agent_share_counts.get(agent_id).copied().unwrap_or(0);
diff --git a/omem-server/src/api/mod.rs b/omem-server/src/api/mod.rs
index 1cb5d98..1b273b2 100644
--- a/omem-server/src/api/mod.rs
+++ b/omem-server/src/api/mod.rs
@@ -1327,7 +1327,10 @@ mod tests {
             .oneshot(
                 Request::builder()
                     .method("POST")
-                    .uri(format!("/v1/spaces/{}/members", utf8_percent_encode(&space_id, NON_ALPHANUMERIC)))
+                    .uri(format!(
+                        "/v1/spaces/{}/members",
+                        utf8_percent_encode(&space_id, NON_ALPHANUMERIC)
+                    ))
                     .header("content-type", "application/json")
                     .header("x-api-key", &api_key)
                     .body(Body::from(r#"{"user_id":"bob","role":"member"}"#))
@@ -1386,7 +1389,10 @@ mod tests {
             .oneshot(
                 Request::builder()
                     .method("DELETE")
-                    .uri(format!("/v1/spaces/{}/members/alice", utf8_percent_encode(&space_id, NON_ALPHANUMERIC)))
+                    .uri(format!(
+                        "/v1/spaces/{}/members/alice",
+                        utf8_percent_encode(&space_id, NON_ALPHANUMERIC)
+                    ))
                     .header("x-api-key", &api_key)
                     .body(Body::empty())
                     .expect("request"),
@@ -1518,7 +1524,10 @@ mod tests {
             .oneshot(
                 Request::builder()
                     .method("DELETE")
-                    .uri(format!("/v1/spaces/{}", utf8_percent_encode(&space_id, NON_ALPHANUMERIC)))
+                    .uri(format!(
+                        "/v1/spaces/{}",
+                        utf8_percent_encode(&space_id, NON_ALPHANUMERIC)
+                    ))
                     .header("x-api-key", &api_key)
                     .body(Body::empty())
                     .expect("request"),
@@ -1532,7 +1541,10 @@ mod tests {
             .clone()
             .oneshot(
                 Request::builder()
-                    .uri(format!("/v1/spaces/{}", utf8_percent_encode(&space_id, NON_ALPHANUMERIC)))
+                    .uri(format!(
+                        "/v1/spaces/{}",
+                        utf8_percent_encode(&space_id, NON_ALPHANUMERIC)
+                    ))
                     .header("x-api-key", &api_key)
                     .body(Body::empty())
                     .expect("request"),
@@ -1578,7 +1590,10 @@ mod tests {
             .oneshot(
                 Request::builder()
                     .method("PUT")
-                    .uri(format!("/v1/spaces/{}/members/carol", utf8_percent_encode(&space_id, NON_ALPHANUMERIC)))
+                    .uri(format!(
+                        "/v1/spaces/{}/members/carol",
+                        utf8_percent_encode(&space_id, NON_ALPHANUMERIC)
+                    ))
                     .header("content-type", "application/json")
                     .header("x-api-key", &api_key)
                     .body(Body::from(r#"{"role":"admin"}"#))
diff --git a/omem-server/src/retrieve/pipeline.rs b/omem-server/src/retrieve/pipeline.rs
index 137d0c2..26d336f 100644
--- a/omem-server/src/retrieve/pipeline.rs
+++ b/omem-server/src/retrieve/pipeline.rs
@@ -1184,7 +1184,10 @@ mod tests {
         ];
 
         let (result, _) = RetrievalPipeline::stage_rrf_normalize(entries);
-        let top = result.iter().find(|e| e.memory.content == "weak-top").unwrap();
+        let top = result
+            .iter()
+            .find(|e| e.memory.content == "weak-top")
+            .unwrap();
         assert!(
             top.rrf_score < 0.25,
             "weak top result should stay below 0.25, got {}",