diff --git a/src/daemon.rs b/src/daemon.rs
index fc3052a..aa0715d 100644
--- a/src/daemon.rs
+++ b/src/daemon.rs
@@ -32,7 +32,8 @@ CREATE TABLE IF NOT EXISTS events (
     start_time  INTEGER,
     end_time    INTEGER,
     duration_ms INTEGER,
-    total_bytes INTEGER
+    total_bytes INTEGER,
+    phases      TEXT
 );
 CREATE INDEX IF NOT EXISTS idx_events_type_start ON events(event_type, start_time, duration_ms, total_bytes);
 CREATE INDEX IF NOT EXISTS idx_events_start_cover ON events(start_time, event_type, duration_ms, total_bytes);
@@ -59,6 +60,7 @@ const SCHEMA_HASHES: &[u32] = &[
     0x7c09711e, // v3: idx_events_start_time(start_time)
     0x24268227, // v4: idx_events_type_start extended to cover (duration_ms, total_bytes); idx_events_start_cover added
     0xfcbb3598, // v5: daily_stats + daily_cache_stats tables
+    0x2d396861, // v6: phases TEXT column on events — compact "phase:elapsed_secs,..." per build
 ];
 const SCHEMA_VERSION: u32 = SCHEMA_HASHES.len() as u32;
 const _: () = assert!(
@@ -140,6 +142,7 @@ const MIGRATIONS: &[(u32, &str)] = &[
             count    = count + excluded.count,
             total_ms = total_ms + excluded.total_ms;
     "),
+    (6, "ALTER TABLE events ADD COLUMN phases TEXT;"),
 ];
 
 #[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize)]
@@ -300,6 +303,8 @@ struct Activity {
     start_time: DateTime<Utc>,
     fields: Vec<serde_json::Value>,
     total_bytes: u64,
+    // (phase_name, elapsed_secs_since_start) — only populated for Build activities.
+    phase_times: Vec<(String, i64)>,
 }
 
 // Per-day aggregate cache, maintained in memory for the current calendar day (UTC).
@@ -712,6 +717,7 @@ fn process_event(event: NixEvent, state: &Arc<Mutex<State>>, db: &Arc<DbConnecti
                 start_time: Utc::now(),
                 fields,
                 total_bytes: 0,
+                phase_times: Vec::new(),
             });
         }
         NixEvent::Result { id, event_type, fields } => {
@@ -727,6 +733,13 @@ fn process_event(event: NixEvent, state: &Arc<Mutex<State>>, db: &Arc<DbConnecti
                         if total > 0 { act.total_bytes = total; }
                     }
                 }
+                if res_type == ResultType::SetPhase {
+                    if let Some(phase_name) = fields.get(0).and_then(|v| v.as_str()) {
+                        let elapsed = Utc::now().signed_duration_since(act.start_time).num_seconds();
+                        assert!(elapsed >= 0, "phase elapsed time must be non-negative");
+                        act.phase_times.push((phase_name.to_string(), elapsed));
+                    }
+                }
             }
         }
         NixEvent::Stop { id } => {
@@ -741,6 +754,12 @@ fn process_event(event: NixEvent, state: &Arc<Mutex<State>>, db: &Arc<DbConnecti
                     "stop"
                 );
 
+                let phases: Option<String> = if act.phase_times.is_empty() {
+                    None
+                } else {
+                    Some(act.phase_times.iter().map(|(name, secs)| format!("{}:{}", name, secs)).collect::<Vec<_>>().join(","))
+                };
+
                 let drv_path = act.fields.get(0).and_then(|v| v.as_str()).map(|s| s.to_string());
                 // Both Substitute (fields[1] = substituter URL) and QueryPathInfo (fields[1] = cache URL)
                 // have the same layout. Store cache_url for both.
@@ -796,13 +815,14 @@ fn process_event(event: NixEvent, state: &Arc<Mutex<State>>, db: &Arc<DbConnecti
                 {
                     let conn = db.writer.lock().unwrap();
                     conn.execute(
-                        "INSERT INTO events (nix_id, parent_id, event_type, text, drv_path, cache_url, start_time, end_time, duration_ms, total_bytes)
-                         VALUES (?1, ?2, ?3, ?4, ?5, ?6, ?7, ?8, ?9, ?10)",
+                        "INSERT INTO events (nix_id, parent_id, event_type, text, drv_path, cache_url, start_time, end_time, duration_ms, total_bytes, phases)
+                         VALUES (?1, ?2, ?3, ?4, ?5, ?6, ?7, ?8, ?9, ?10, ?11)",
                         rusqlite::params![
                             act.id as i64, act.parent_id as i64, act.event_type as i64,
                             act.text, drv_path, cache_url.as_deref(),
                             act.start_time.timestamp(), end_time.timestamp(),
                             duration_ms, act.total_bytes as i64,
+                            phases,
                         ],
                     ).context("Failed to insert event")?;