diff --git a/index.ts b/index.ts
index cc3dd25..9e66db1 100644
--- a/index.ts
+++ b/index.ts
@@ -8,7 +8,7 @@ export class Console implements Writer {
         readonly _options: WriterOptions
     ) {}
 
-    private static get_logger(level: Level) {
+    private static get_logger(level: Level) : (...data: any[]) => void {
         switch (level) {
             case Level.DEBUG: return console.debug
             case Level.TRACE: return console.debug