diff --git a/migrations/202203191_drop_diagnostics_user.go b/migrations/202203191_drop_diagnostics_user.go
new file mode 100644
index 0000000..8146e8a
--- /dev/null
+++ b/migrations/202203191_drop_diagnostics_user.go
@@ -0,0 +1,39 @@
+package migrations
+
+import (
+	"github.com/emvi/logbuch"
+	"github.com/muety/wakapi/config"
+	"github.com/muety/wakapi/models"
+	"gorm.io/gorm"
+)
+
+func init() {
+	const name = "202203191-drop_diagnostics_user"
+	f := migrationFunc{
+		name: name,
+		f: func(db *gorm.DB, cfg *config.Config) error {
+			if hasRun(name, db) {
+				return nil
+			}
+
+			migrator := db.Migrator()
+
+			if migrator.HasColumn(&models.Diagnostics{}, "user_id") {
+				logbuch.Info("running migration '%s'", name)
+
+				if err := migrator.DropConstraint(&models.Diagnostics{}, "fk_diagnostics_user"); err != nil {
+					logbuch.Warn("failed to drop 'fk_diagnostics_user' constraint (%v)", err)
+				}
+
+				if err := migrator.DropColumn(&models.Diagnostics{}, "user_id"); err != nil {
+					logbuch.Warn("failed to drop user_id column of diagnostics (%v)", err)
+				}
+			}
+
+			setHasRun(name, db)
+			return nil
+		},
+	}
+
+	registerPostMigration(f)
+}
diff --git a/models/diagnostics.go b/models/diagnostics.go
index d5126e2..6031edd 100644
--- a/models/diagnostics.go
+++ b/models/diagnostics.go
@@ -2,8 +2,6 @@ package models
 
 type Diagnostics struct {
 	ID           uint   `gorm:"primary_key"`
-	User         *User  `json:"-" gorm:"not null; constraint:OnUpdate:CASCADE,OnDelete:CASCADE"`
-	UserID       string `json:"-" gorm:"not null; index:idx_diagnostics_user"`
 	Platform     string `json:"platform"`
 	Architecture string `json:"architecture"`
 	Plugin       string `json:"plugin"`
diff --git a/routes/api/diagnostics.go b/routes/api/diagnostics.go
index e63be87..f903dbe 100644
--- a/routes/api/diagnostics.go
+++ b/routes/api/diagnostics.go
@@ -46,20 +46,12 @@ func (h *DiagnosticsApiHandler) RegisterRoutes(router *mux.Router) {
 func (h *DiagnosticsApiHandler) Post(w http.ResponseWriter, r *http.Request) {
 	var diagnostics models.Diagnostics
 
-	user := middlewares.GetPrincipal(r)
-	if user == nil {
-		w.WriteHeader(http.StatusUnauthorized)
-		w.Write([]byte(conf.ErrUnauthorized))
-		return
-	}
-
 	if err := json.NewDecoder(r.Body).Decode(&diagnostics); err != nil {
 		w.WriteHeader(http.StatusBadRequest)
 		w.Write([]byte(conf.ErrBadRequest))
 		conf.Log().Request(r).Error("failed to parse diagnostics for user %s - %v", err)
 		return
 	}
-	diagnostics.UserID = user.ID
 
 	if _, err := h.diagnosticsSrvc.Create(&diagnostics); err != nil {
 		w.WriteHeader(http.StatusInternalServerError)