diff --git a/internal/config/config.go b/internal/config/config.go
index 4912e43..e040541 100644
--- a/internal/config/config.go
+++ b/internal/config/config.go
@@ -685,8 +685,10 @@ func checkConfig(config *Config) error {
 			}
 
 			r := task.Runtime
-			if r.Type != RuntimeTypePod {
-				return errors.Errorf("task %q runtime: wrong type %q", task.Name, r.Type)
+			if r.Type != "" {
+				if r.Type != RuntimeTypePod {
+					return errors.Errorf("task %q runtime: wrong type %q", task.Name, r.Type)
+				}
 			}
 			if len(r.Containers) == 0 {
 				return errors.Errorf("task %q runtime: at least one container must be defined", task.Name)
@@ -801,6 +803,12 @@ func checkConfig(config *Config) error {
 				task.WorkingDir = defaultWorkingDir
 			}
 
+			// set task runtime type to pod if empty
+			r := task.Runtime
+			if r.Type == "" {
+				r.Type = RuntimeTypePod
+			}
+
 			// set steps defaults
 			for i, s := range task.Steps {
 				switch step := s.(type) {
diff --git a/internal/runconfig/runconfig.go b/internal/runconfig/runconfig.go
index 6747285..e948cf7 100644
--- a/internal/runconfig/runconfig.go
+++ b/internal/runconfig/runconfig.go
@@ -22,6 +22,7 @@ import (
 	rstypes "github.com/sorintlab/agola/internal/services/runservice/types"
 	"github.com/sorintlab/agola/internal/services/types"
 	"github.com/sorintlab/agola/internal/util"
+
 	errors "golang.org/x/xerrors"
 )