diff --git a/packages/taler-wallet-cli/src/harness/harness.ts b/packages/taler-wallet-cli/src/harness/harness.ts
index b4ac16dbf..c607144e0 100644
--- a/packages/taler-wallet-cli/src/harness/harness.ts
+++ b/packages/taler-wallet-cli/src/harness/harness.ts
@@ -607,118 +607,126 @@ export namespace BankApi {
   }
 }
 
-export class BankService implements BankServiceInterface {
-  proc: ProcessWrapper | undefined;
-
-  static fromExistingConfig(gc: GlobalTestState): BankService {
-    const cfgFilename = gc.testDir + "/bank.conf";
-    console.log("reading bank config from", cfgFilename);
-    const config = Configuration.load(cfgFilename);
-    const bc: BankConfig = {
-      allowRegistrations: config
-        .getYesNo("bank", "allow_registrations")
-        .required(),
-      currency: config.getString("taler", "currency").required(),
-      database: config.getString("bank", "database").required(),
-      httpPort: config.getNumber("bank", "http_port").required(),
-    };
-    return new BankService(gc, bc, cfgFilename);
-  }
-
-  static async create(
-    gc: GlobalTestState,
-    bc: BankConfig,
-  ): Promise<BankService> {
-    const config = new Configuration();
-    setTalerPaths(config, gc.testDir + "/talerhome");
-    config.setString("taler", "currency", bc.currency);
-    config.setString("bank", "database", bc.database);
-    config.setString("bank", "http_port", `${bc.httpPort}`);
-    config.setString("bank", "serve", "http");
-    config.setString("bank", "max_debt_bank", `${bc.currency}:999999`);
-    config.setString("bank", "max_debt", bc.maxDebt ?? `${bc.currency}:100`);
-    config.setString(
-      "bank",
-      "allow_registrations",
-      bc.allowRegistrations ? "yes" : "no",
-    );
-    const cfgFilename = gc.testDir + "/bank.conf";
-    config.write(cfgFilename);
-
-    await sh(
-      gc,
-      "taler-bank-manage_django",
-      `taler-bank-manage -c '${cfgFilename}' django migrate`,
-    );
-    await sh(
-      gc,
-      "taler-bank-manage_django",
-      `taler-bank-manage -c '${cfgFilename}' django provide_accounts`,
-    );
-
-    return new BankService(gc, bc, cfgFilename);
-  }
-
-  setSuggestedExchange(e: ExchangeServiceInterface, exchangePayto: string) {
-    const config = Configuration.load(this.configFile);
-    config.setString("bank", "suggested_exchange", e.baseUrl);
-    config.setString("bank", "suggested_exchange_payto", exchangePayto);
-  }
-
-  get baseUrl(): string {
-    return `http://localhost:${this.bankConfig.httpPort}/`;
-  }
-
-  async createExchangeAccount(
-    accountName: string,
-    password: string,
-  ): Promise<HarnessExchangeBankAccount> {
-    await sh(
-      this.globalTestState,
-      "taler-bank-manage_django",
-      `taler-bank-manage -c '${this.configFile}' django add_bank_account ${accountName}`,
-    );
-    await sh(
-      this.globalTestState,
-      "taler-bank-manage_django",
-      `taler-bank-manage -c '${this.configFile}' django changepassword_unsafe ${accountName} ${password}`,
-    );
-    await sh(
-      this.globalTestState,
-      "taler-bank-manage_django",
-      `taler-bank-manage -c '${this.configFile}' django top_up ${accountName} ${this.bankConfig.currency}:100000`,
-    );
-    return {
-      accountName: accountName,
-      accountPassword: password,
-      accountPaytoUri: `payto://x-taler-bank/${accountName}`,
-      wireGatewayApiBaseUrl: `http://localhost:${this.bankConfig.httpPort}/taler-wire-gateway/${accountName}/`,
-    };
-  }
-
-  get port() {
-    return this.bankConfig.httpPort;
-  }
-
-  private constructor(
-    private globalTestState: GlobalTestState,
-    private bankConfig: BankConfig,
-    private configFile: string,
-  ) {}
-
-  async start(): Promise<void> {
-    this.proc = this.globalTestState.spawnService(
-      "taler-bank-manage",
-      ["-c", this.configFile, "serve"],
-      "bank",
-    );
-  }
-
-  async pingUntilAvailable(): Promise<void> {
-    const url = `http://localhost:${this.bankConfig.httpPort}/config`;
-    await pingProc(this.proc, url, "bank");
+/**
+ * Method explained here:
+ * https://github.com/microsoft/TypeScript/issues/2552
+ */
+module BankServices {
+  export class PybankService implements BankServiceInterface {
+    proc: ProcessWrapper | undefined;
+  
+    static fromExistingConfig(gc: GlobalTestState): BankService {
+      const cfgFilename = gc.testDir + "/bank.conf";
+      console.log("reading bank config from", cfgFilename);
+      const config = Configuration.load(cfgFilename);
+      const bc: BankConfig = {
+        allowRegistrations: config
+          .getYesNo("bank", "allow_registrations")
+          .required(),
+        currency: config.getString("taler", "currency").required(),
+        database: config.getString("bank", "database").required(),
+        httpPort: config.getNumber("bank", "http_port").required(),
+      };
+      return new BankService(gc, bc, cfgFilename);
+    }
+  
+    static async create(
+      gc: GlobalTestState,
+      bc: BankConfig,
+    ): Promise<BankService> {
+      const config = new Configuration();
+      setTalerPaths(config, gc.testDir + "/talerhome");
+      config.setString("taler", "currency", bc.currency);
+      config.setString("bank", "database", bc.database);
+      config.setString("bank", "http_port", `${bc.httpPort}`);
+      config.setString("bank", "serve", "http");
+      config.setString("bank", "max_debt_bank", `${bc.currency}:999999`);
+      config.setString("bank", "max_debt", bc.maxDebt ?? `${bc.currency}:100`);
+      config.setString(
+        "bank",
+        "allow_registrations",
+        bc.allowRegistrations ? "yes" : "no",
+      );
+      const cfgFilename = gc.testDir + "/bank.conf";
+      config.write(cfgFilename);
+  
+      await sh(
+        gc,
+        "taler-bank-manage_django",
+        `taler-bank-manage -c '${cfgFilename}' django migrate`,
+      );
+      await sh(
+        gc,
+        "taler-bank-manage_django",
+        `taler-bank-manage -c '${cfgFilename}' django provide_accounts`,
+      );
+  
+      return new BankService(gc, bc, cfgFilename);
+    }
+  
+    setSuggestedExchange(e: ExchangeServiceInterface, exchangePayto: string) {
+      const config = Configuration.load(this.configFile);
+      config.setString("bank", "suggested_exchange", e.baseUrl);
+      config.setString("bank", "suggested_exchange_payto", exchangePayto);
+    }
+  
+    get baseUrl(): string {
+      return `http://localhost:${this.bankConfig.httpPort}/`;
+    }
+  
+    async createExchangeAccount(
+      accountName: string,
+      password: string,
+    ): Promise<HarnessExchangeBankAccount> {
+      await sh(
+        this.globalTestState,
+        "taler-bank-manage_django",
+        `taler-bank-manage -c '${this.configFile}' django add_bank_account ${accountName}`,
+      );
+      await sh(
+        this.globalTestState,
+        "taler-bank-manage_django",
+        `taler-bank-manage -c '${this.configFile}' django changepassword_unsafe ${accountName} ${password}`,
+      );
+      await sh(
+        this.globalTestState,
+        "taler-bank-manage_django",
+        `taler-bank-manage -c '${this.configFile}' django top_up ${accountName} ${this.bankConfig.currency}:100000`,
+      );
+      return {
+        accountName: accountName,
+        accountPassword: password,
+        accountPaytoUri: `payto://x-taler-bank/${accountName}`,
+        wireGatewayApiBaseUrl: `http://localhost:${this.bankConfig.httpPort}/taler-wire-gateway/${accountName}/`,
+      };
+    }
+  
+    get port() {
+      return this.bankConfig.httpPort;
+    }
+  
+    private constructor(
+      private globalTestState: GlobalTestState,
+      private bankConfig: BankConfig,
+      private configFile: string,
+    ) {}
+  
+    async start(): Promise<void> {
+      this.proc = this.globalTestState.spawnService(
+        "taler-bank-manage",
+        ["-c", this.configFile, "serve"],
+        "bank",
+      );
+    }
+  
+    async pingUntilAvailable(): Promise<void> {
+      const url = `http://localhost:${this.bankConfig.httpPort}/config`;
+      await pingProc(this.proc, url, "bank");
+    }
   }
 }
+import BankService = BankServices.PybankService;
+export { BankService };
 
 export class FakeBankService {
   proc: ProcessWrapper | undefined;