diff --git a/lib/formatters/formatter.ts b/lib/formatters/formatter.ts
index 4f1ffcca..39d4202d 100644
--- a/lib/formatters/formatter.ts
+++ b/lib/formatters/formatter.ts
@@ -1,19 +1,18 @@
-import { CSVFormatter } from "./csv_formatter.js";
-
 export abstract class Formatter {
 
   abstract header(sampleData: object, fastaMapper?: boolean): string;
   abstract footer(): string;
-  abstract convert(data: any, first?: boolean): string;
+  abstract convert(data: { [key: string]: string }[], first?: boolean): string;
 
-  format(data, fastaMapper?: boolean, first?: boolean): string {
+  format(data: { [key: string]: string }[], fastaMapper?: boolean, first?: boolean): string {
     if (fastaMapper) {
       data = this.integrateFastaHeaders(data, fastaMapper);
     }
     return this.convert(data, first);
   }
 
-  integrateFastaHeaders(data: any, fastaMapper: boolean): any {
+  // eslint-disable-next-line @typescript-eslint/no-unused-vars
+  integrateFastaHeaders(data: { [key: string]: string }[], fastaMapper: boolean): { [key: string]: string }[] {
     return data;
   }
 }