diff --git a/src/libstore/build/worker.cc b/src/libstore/build/worker.cc
index 974a9f510..d57e22393 100644
--- a/src/libstore/build/worker.cc
+++ b/src/libstore/build/worker.cc
@@ -251,7 +251,7 @@ void Worker::childTerminated(Goal * goal, bool wakeSleepers)
 
 void Worker::waitForBuildSlot(GoalPtr goal)
 {
-    debug("wait for build slot");
+    goal->trace("wait for build slot");
     bool isSubstitutionGoal = goal->jobCategory() == JobCategory::Substitution;
     if ((!isSubstitutionGoal && getNrLocalBuilds() < settings.maxBuildJobs) ||
         (isSubstitutionGoal && getNrSubstitutions() < settings.maxSubstitutionJobs))
diff --git a/src/libstore/local-store.cc b/src/libstore/local-store.cc
index 5a399c8be..07068f8f8 100644
--- a/src/libstore/local-store.cc
+++ b/src/libstore/local-store.cc
@@ -1049,7 +1049,11 @@ void LocalStore::addToStore(const ValidPathInfo & info, Source & source,
     Finally cleanup = [&]() {
         if (!narRead) {
             NullParseSink sink;
-            parseDump(sink, source);
+            try {
+                parseDump(sink, source);
+            } catch (...) {
+                ignoreException();
+            }
         }
     };
 
diff --git a/src/libstore/store-api.cc b/src/libstore/store-api.cc
index 0c37ecd30..9cb187e66 100644
--- a/src/libstore/store-api.cc
+++ b/src/libstore/store-api.cc
@@ -981,6 +981,11 @@ void copyStorePath(
     RepairFlag repair,
     CheckSigsFlag checkSigs)
 {
+    /* Bail out early (before starting a download from srcStore) if
+       dstStore already has this path. */
+    if (!repair && dstStore.isValidPath(storePath))
+        return;
+
     auto srcUri = srcStore.getUri();
     auto dstUri = dstStore.getUri();
     auto storePathS = srcStore.printStorePath(storePath);