1 files changed, 2 insertions, 2 deletions
diff --git a/packages/kovan-faucets/src/ts/id_management.ts b/packages/kovan-faucets/src/ts/id_management.ts
index 74865afb8..930821172 100644
--- a/packages/kovan-faucets/src/ts/id_management.ts
+++ b/packages/kovan-faucets/src/ts/id_management.ts
@@ -3,7 +3,7 @@ import EthereumTx = require('ethereumjs-tx');
 import { configs } from './configs';
 import { utils } from './utils';
 
-type Callback = (err: Error, accounts: any) => void;
+type Callback = (err: Error | null, accounts: any) => void;
 
 export const idManagement = {
     getAccounts(callback: Callback) {
@@ -15,7 +15,7 @@ export const idManagement = {
     },
     signTransaction(txData: object, callback: Callback) {
         const tx = new EthereumTx(txData);
-        const privateKeyBuffer = new Buffer(configs.DISPENSER_PRIVATE_KEY, 'hex');
+        const privateKeyBuffer = new Buffer(configs.DISPENSER_PRIVATE_KEY as string, 'hex');
         tx.sign(privateKeyBuffer);
         const rawTx = `0x${tx.serialize().toString('hex')}`;
         callback(null, rawTx);