diff --git a/internal/ui/backup.go b/internal/ui/backup.go
index 17181dc70..53bc2117e 100644
--- a/internal/ui/backup.go
+++ b/internal/ui/backup.go
@@ -19,6 +19,9 @@ type Backup struct {
 	term *termstatus.Terminal
 }
 
+// assert that Backup implements the ProgressPrinter interface
+var _ ProgressPrinter = &Backup{}
+
 // NewBackup returns a new backup progress reporter.
 func NewBackup(term *termstatus.Terminal, verbosity uint) *Backup {
 	return &Backup{
diff --git a/internal/ui/json/backup.go b/internal/ui/json/backup.go
index acaa394bc..6c19089df 100644
--- a/internal/ui/json/backup.go
+++ b/internal/ui/json/backup.go
@@ -22,6 +22,9 @@ type Backup struct {
 	v    uint
 }
 
+// assert that Backup implements the ProgressPrinter interface
+var _ ui.ProgressPrinter = &Backup{}
+
 // NewBackup returns a new backup progress reporter.
 func NewBackup(term *termstatus.Terminal, verbosity uint) *Backup {
 	return &Backup{