diff --git a/internal/git/housekeeping/manager/optimize_repository.go b/internal/git/housekeeping/manager/optimize_repository.go
index 838ad454e4e823c3b15c10e6bb73b7c34032072e..095aee543152a811aa95136b33c5a832b1c2260c 100644
--- a/internal/git/housekeeping/manager/optimize_repository.go
+++ b/internal/git/housekeeping/manager/optimize_repository.go
@@ -6,6 +6,7 @@ import (
 	"errors"
 	"fmt"
 	"os"
+	"reflect"
 
 	"gitlab.com/gitlab-org/gitaly/v16/internal/git/gitcmd"
 	"gitlab.com/gitlab-org/gitaly/v16/internal/git/housekeeping"
@@ -98,7 +99,7 @@ func (m *RepositoryManager) OptimizeRepository(
 }
 
 func (m *RepositoryManager) maybeStartTransaction(ctx context.Context, repo *localrepo.Repo, run func(context.Context, storage.Transaction, *localrepo.Repo) error) error {
-	if m.node == nil {
+	if m.node == nil || reflect.ValueOf(m.node).IsNil() {
 		return run(ctx, nil, repo)
 	}
 
diff --git a/internal/git/housekeeping/manager/optimize_repository_test.go b/internal/git/housekeeping/manager/optimize_repository_test.go
index 1cd9c94246f79f68711c538d26ed83af796fd2cc..7663d04fb5e8b0841db0339a23723394942a5de4 100644
--- a/internal/git/housekeeping/manager/optimize_repository_test.go
+++ b/internal/git/housekeeping/manager/optimize_repository_test.go
@@ -7,6 +7,7 @@ import (
 	"fmt"
 	"os"
 	"path/filepath"
+	"reflect"
 	"runtime"
 	"sync"
 	"testing"
@@ -1089,7 +1090,7 @@ func TestOptimizeRepository(t *testing.T) {
 				require.Equal(t, setup.expectedErr, err)
 
 				expectedMetrics := setup.expectedMetrics
-				if node != nil && setup.expectedMetricsForTransaction != nil {
+				if node != nil && !reflect.ValueOf(node).IsNil() && setup.expectedMetricsForTransaction != nil {
 					expectedMetrics = setup.expectedMetricsForTransaction
 				}
 				// If object pool is enabled, asserting transaction's metrics using
diff --git a/internal/git/housekeeping/manager/testhelper_test.go b/internal/git/housekeeping/manager/testhelper_test.go
index 74317abd784a91d60dfcf4f2881111ae13a93a51..c91448bdba596e3cd3944b4262e4a774013b73b3 100644
--- a/internal/git/housekeeping/manager/testhelper_test.go
+++ b/internal/git/housekeeping/manager/testhelper_test.go
@@ -122,8 +122,11 @@ func testWithAndWithoutTransaction(t *testing.T, desc string, testFunc func(*tes
 		})
 
 		t.Run("without transaction", func(t *testing.T) {
+			// Make sure to pass a nil struct rather than an explicit `nil` value to the housekeeping
+			// manager, as this exercises our nil interface check using reflection.
+			var node *nodeimpl.Manager
 			cfg := testcfg.Build(t)
-			testFunc(t, cfg, nil)
+			testFunc(t, cfg, node)
 		})
 	})
 }