diff --git a/lix/libstore/build/derivation-goal.cc b/lix/libstore/build/derivation-goal.cc
index 0c7cf27b0..ca024c960 100644
--- a/lix/libstore/build/derivation-goal.cc
+++ b/lix/libstore/build/derivation-goal.cc
@@ -1250,6 +1250,11 @@ try {
         lastChildActivity = AIO().provider.getTimer().now();
 
         if (data.empty()) {
+            if (!currentLogLine.empty()) {
+                if (flushLine() == Logger::BufferState::NeedsFlush) {
+                    TRY_AWAIT(act->getLogger().flush());
+                }
+            }
             co_return std::nullopt;
         }
 
@@ -1359,11 +1364,7 @@ try {
         );
     }
 
-    const auto r = TRY_AWAIT(handlers);
-    if (!currentLogLine.empty() && flushLine() == Logger::BufferState::NeedsFlush) {
-        TRY_AWAIT(act->getLogger().flush());
-    }
-    co_return r;
+    co_return TRY_AWAIT(handlers);
 } catch (...) {
     co_return result::current_exception();
 }
diff --git a/tests/functional/build-hook-ca-fixed.nix b/tests/functional/build-hook-ca-fixed.nix
index 0ce6d9b12..3da2de92c 100644
--- a/tests/functional/build-hook-ca-fixed.nix
+++ b/tests/functional/build-hook-ca-fixed.nix
@@ -36,8 +36,9 @@ let
   input3 = mkDerivation {
     shell = busybox;
     name = "build-remote-input-3";
+    # `echo -n` tests handling of logs without trailing newlines
     buildCommand = ''
-      echo hi-input3
+      echo -n hi-input3
       read x < ${input2}
       echo $x BAZ > $out
     '';
diff --git a/tests/functional/build-hook.nix b/tests/functional/build-hook.nix
index 99a13aee4..8f17f7033 100644
--- a/tests/functional/build-hook.nix
+++ b/tests/functional/build-hook.nix
@@ -39,8 +39,9 @@ let
   input3 = mkDerivation {
     shell = busybox;
     name = "build-remote-input-3";
+    # `echo -n` tests handling of logs without trailing newlines
     buildCommand = ''
-      echo hi-input3
+      echo -n hi-input3
       read x < ${input2}
       echo $x BAZ > $out
     '';