diff --git a/frontend/packages/dashboard/src/tabs.js b/frontend/packages/dashboard/src/tabs.js
index 34b348f2..c822e739 100644
--- a/frontend/packages/dashboard/src/tabs.js
+++ b/frontend/packages/dashboard/src/tabs.js
@@ -1127,7 +1127,7 @@ window.marked = marked;
             const age = h.started_at
               ? fmtAgeSecs(nowUnix - h.started_at) + ' ago' : '?';
             const runtimeSpan = h.runtime_secs != null
-              ? el('span', { class: 'build-logs-runtime meta' }, fmtDuration(h.runtime_secs))
+              ? el('span', { class: 'build-logs-runtime meta' }, fmtDuration(Math.max(0, h.runtime_secs)))
               : h.started_at && !h.finished_at
                 ? el('span', {
                     class: 'build-logs-runtime meta',
diff --git a/hive-c0re/src/build_logs.rs b/hive-c0re/src/build_logs.rs
index 31fcafd4..1492dbd6 100644
--- a/hive-c0re/src/build_logs.rs
+++ b/hive-c0re/src/build_logs.rs
@@ -333,7 +333,7 @@ impl BuildLogs {
             .query_row(params![id], |r| {
                 let started_at: i64 = r.get(4)?;
                 let finished_at: Option<i64> = r.get(5)?;
-                let runtime_secs = finished_at.map(|f| f - started_at);
+                let runtime_secs = compute_runtime_secs(started_at, finished_at);
                 Ok(BuildLogFull {
                     header: BuildLogHeader {
                         id: r.get(0)?,
@@ -410,10 +410,14 @@ pub fn spawn_vacuum(coord: &Arc<crate::coordinator::Coordinator>) {
     });
 }
 
+fn compute_runtime_secs(started_at: i64, finished_at: Option<i64>) -> Option<i64> {
+    finished_at.map(|f| f - started_at)
+}
+
 fn row_to_header(r: &rusqlite::Row) -> rusqlite::Result<BuildLogHeader> {
     let started_at: i64 = r.get(4)?;
     let finished_at: Option<i64> = r.get(5)?;
-    let runtime_secs = finished_at.map(|f| f - started_at);
+    let runtime_secs = compute_runtime_secs(started_at, finished_at);
     Ok(BuildLogHeader {
         id: r.get(0)?,
         agent: r.get(1)?,