diff --git a/pkg/api/handlers/compat/containers.go b/pkg/api/handlers/compat/containers.go
index 5886455e72..7a3e5dd847 100644
--- a/pkg/api/handlers/compat/containers.go
+++ b/pkg/api/handlers/compat/containers.go
@@ -17,6 +17,7 @@ import (
 	"github.com/docker/docker/api/types"
 	"github.com/docker/docker/api/types/container"
 	"github.com/docker/go-connections/nat"
+	"github.com/gorilla/mux"
 	"github.com/gorilla/schema"
 	"github.com/pkg/errors"
 	"github.com/sirupsen/logrus"
@@ -73,7 +74,7 @@ func RemoveContainer(w http.ResponseWriter, r *http.Request) {
 		utils.InternalServerError(w, err)
 		return
 	}
-	utils.WriteResponse(w, http.StatusNoContent, "")
+	utils.WriteResponse(w, http.StatusNoContent, nil)
 }
 
 func ListContainers(w http.ResponseWriter, r *http.Request) {
@@ -207,7 +208,7 @@ func KillContainer(w http.ResponseWriter, r *http.Request) {
 		}
 	}
 	// Success
-	utils.WriteResponse(w, http.StatusNoContent, "")
+	utils.WriteResponse(w, http.StatusNoContent, nil)
 }
 
 func WaitContainer(w http.ResponseWriter, r *http.Request) {
@@ -215,8 +216,10 @@ func WaitContainer(w http.ResponseWriter, r *http.Request) {
 	// /{version}/containers/(name)/wait
 	exitCode, err := utils.WaitContainer(w, r)
 	if err != nil {
+		logrus.Warnf("failed to wait on container %q: %v", mux.Vars(r)["name"], err)
 		return
 	}
+
 	utils.WriteResponse(w, http.StatusOK, handlers.ContainerWaitOKBody{
 		StatusCode: int(exitCode),
 		Error: struct {
diff --git a/pkg/api/handlers/compat/containers_pause.go b/pkg/api/handlers/compat/containers_pause.go
index 8712969c00..a7e0a66f16 100644
--- a/pkg/api/handlers/compat/containers_pause.go
+++ b/pkg/api/handlers/compat/containers_pause.go
@@ -24,5 +24,5 @@ func PauseContainer(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 	// Success
-	utils.WriteResponse(w, http.StatusNoContent, "")
+	utils.WriteResponse(w, http.StatusNoContent, nil)
 }
diff --git a/pkg/api/handlers/compat/containers_restart.go b/pkg/api/handlers/compat/containers_restart.go
index f4d8f06a1d..e8928596a5 100644
--- a/pkg/api/handlers/compat/containers_restart.go
+++ b/pkg/api/handlers/compat/containers_restart.go
@@ -41,5 +41,5 @@ func RestartContainer(w http.ResponseWriter, r *http.Request) {
 	}
 
 	// Success
-	utils.WriteResponse(w, http.StatusNoContent, "")
+	utils.WriteResponse(w, http.StatusNoContent, nil)
 }
diff --git a/pkg/api/handlers/compat/containers_start.go b/pkg/api/handlers/compat/containers_start.go
index 6236b13570..726da6f99e 100644
--- a/pkg/api/handlers/compat/containers_start.go
+++ b/pkg/api/handlers/compat/containers_start.go
@@ -39,12 +39,12 @@ func StartContainer(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 	if state == define.ContainerStateRunning {
-		utils.WriteResponse(w, http.StatusNotModified, "")
+		utils.WriteResponse(w, http.StatusNotModified, nil)
 		return
 	}
 	if err := con.Start(r.Context(), len(con.PodID()) > 0); err != nil {
 		utils.InternalServerError(w, err)
 		return
 	}
-	utils.WriteResponse(w, http.StatusNoContent, "")
+	utils.WriteResponse(w, http.StatusNoContent, nil)
 }
diff --git a/pkg/api/handlers/compat/containers_stop.go b/pkg/api/handlers/compat/containers_stop.go
index 13fe253389..8bc58cf59d 100644
--- a/pkg/api/handlers/compat/containers_stop.go
+++ b/pkg/api/handlers/compat/containers_stop.go
@@ -40,7 +40,7 @@ func StopContainer(w http.ResponseWriter, r *http.Request) {
 	}
 	// If the Container is stopped already, send a 304
 	if state == define.ContainerStateStopped || state == define.ContainerStateExited {
-		utils.WriteResponse(w, http.StatusNotModified, "")
+		utils.WriteResponse(w, http.StatusNotModified, nil)
 		return
 	}
 
@@ -56,5 +56,5 @@ func StopContainer(w http.ResponseWriter, r *http.Request) {
 	}
 
 	// Success
-	utils.WriteResponse(w, http.StatusNoContent, "")
+	utils.WriteResponse(w, http.StatusNoContent, nil)
 }
diff --git a/pkg/api/handlers/compat/containers_unpause.go b/pkg/api/handlers/compat/containers_unpause.go
index f87b95b644..760e85814a 100644
--- a/pkg/api/handlers/compat/containers_unpause.go
+++ b/pkg/api/handlers/compat/containers_unpause.go
@@ -24,5 +24,5 @@ func UnpauseContainer(w http.ResponseWriter, r *http.Request) {
 	}
 
 	// Success
-	utils.WriteResponse(w, http.StatusNoContent, "")
+	utils.WriteResponse(w, http.StatusNoContent, nil)
 }