diff --git a/zooid/api.go b/zooid/api.go
index aaae1fe..c36adac 100644
--- a/zooid/api.go
+++ b/zooid/api.go
@@ -7,6 +7,7 @@ import (
 	"net/http"
 	"os"
 	"path/filepath"
+	"regexp"
 	"strings"
 
 	"fiatjaf.com/nostr"
@@ -285,6 +286,9 @@ func (api *APIHandler) validatePatchedConfig(config *Config) error {
 	if config.Schema == "" {
 		return fmt.Errorf("schema is required")
 	}
+	if !regexp.MustCompile(`^[a-zA-Z_][a-zA-Z0-9_]*$`).MatchString(config.Schema) {
+		return fmt.Errorf("schema must contain only letters, numbers, and underscores")
+	}
 	if config.Secret == "" {
 		return fmt.Errorf("secret is required")
 	}
diff --git a/zooid/instance.go b/zooid/instance.go
index d5da9c4..2c05ded 100644
--- a/zooid/instance.go
+++ b/zooid/instance.go
@@ -122,7 +122,7 @@ func MakeInstance(filename string) (*Instance, error) {
 	// Initialize the database
 
 	if err := instance.Events.Init(); err != nil {
-		log.Fatal("Failed to initialize event store: ", err)
+		log.Fatal("Failed to initialize event store for ", filename, ": ", err)
 	}
 
 	// Enable extra functionality