diff --git a/benchmark/index.js b/benchmark/index.js
index 49f1d5dc4a..f150c79f28 100644
--- a/benchmark/index.js
+++ b/benchmark/index.js
@@ -1,3 +1,5 @@
+'use strict';
+
 const cronometro = require('cronometro'),
     newRedis = require('redis-new'),
     oldRedis = require('redis-old');
diff --git a/lib/commands-queue.ts b/lib/commands-queue.ts
index 2a5e822336..f81c7f3648 100644
--- a/lib/commands-queue.ts
+++ b/lib/commands-queue.ts
@@ -6,12 +6,12 @@ import { RedisReply } from './commands';
 export interface QueueCommandOptions {
     asap?: boolean;
     signal?: AbortSignal;
-    chainId?: Symbol;
+    chainId?: symbol;
 }
 
 interface CommandWaitingToBeSent extends CommandWaitingForReply {
     encodedCommand: string;
-    chainId?: Symbol;
+    chainId?: symbol;
     abort?: {
         signal: AbortSignal;
         listener(): void;
@@ -119,7 +119,7 @@ export default class RedisCommandsQueue {
         returnError: (err: Error) => this.#shiftWaitingForReply().reject(err)
     });
 
-    #chainInExecution: Symbol | undefined;
+    #chainInExecution: symbol | undefined;
 
     constructor(maxLength: number | null | undefined, executor: CommandsQueueExecutor) {
         this.#maxLength = maxLength;
@@ -293,7 +293,7 @@ export default class RedisCommandsQueue {
 
         const encoded: Array<string> = [];
         let size = 0,
-            lastCommandChainId: Symbol | undefined;
+            lastCommandChainId: symbol | undefined;
         for (const command of this.#waitingToBeSent) {
             encoded.push(command.encodedCommand);
             size += command.encodedCommand.length;
diff --git a/lib/commands/ACL_LOG.ts b/lib/commands/ACL_LOG.ts
index ba3cddf0e8..ed0590b578 100644
--- a/lib/commands/ACL_LOG.ts
+++ b/lib/commands/ACL_LOG.ts
@@ -31,7 +31,7 @@ interface AclLog {
     context: string;
     object: string;
     username: string;
-    ageSeconds: Number;
+    ageSeconds: number;
     clientInfo: string;
 }
 
diff --git a/lib/commands/CLUSTER_NODES.spec.ts b/lib/commands/CLUSTER_NODES.spec.ts
index b577b631fe..1f0e9dd425 100644
--- a/lib/commands/CLUSTER_NODES.spec.ts
+++ b/lib/commands/CLUSTER_NODES.spec.ts
@@ -95,8 +95,6 @@ describe('CLUSTER NODES', () => {
     });
 
     itWithCluster(TestRedisClusters.OPEN, 'cluster.clusterNodes', async cluster => {
-        const nodes = await cluster.clusterNodes();
-
         for (const node of (await cluster.clusterNodes())) {
             assert.equal(typeof node.id, 'string');
             assert.equal(typeof node.url, 'string');
diff --git a/lib/commands/SET.spec.ts b/lib/commands/SET.spec.ts
index 8515950fd3..5ddb97989f 100644
--- a/lib/commands/SET.spec.ts
+++ b/lib/commands/SET.spec.ts
@@ -81,7 +81,7 @@ describe('SET', () => {
         it('with GET', () => {
             assert.deepEqual(
                 transformArguments('key', 'value', {
-                    GET: 1
+                    GET: true
                 }),
                 ['SET', 'key', 'value', 'GET']
             );
diff --git a/lib/commands/XINFO_STREAM.spec.ts b/lib/commands/XINFO_STREAM.spec.ts
index 76db1b647e..ecab605e4e 100644
--- a/lib/commands/XINFO_STREAM.spec.ts
+++ b/lib/commands/XINFO_STREAM.spec.ts
@@ -1,5 +1,4 @@
 import { strict as assert } from 'assert';
-import { triggerAsyncId } from 'async_hooks';
 import { TestRedisServers, itWithClient } from '../test-utils';
 import { transformArguments, transformReply } from './XINFO_STREAM';
 
diff --git a/lib/commands/XPENDING_RANGE.ts b/lib/commands/XPENDING_RANGE.ts
index f76da6e8dd..c9e8d898e8 100644
--- a/lib/commands/XPENDING_RANGE.ts
+++ b/lib/commands/XPENDING_RANGE.ts
@@ -32,11 +32,4 @@ export function transformArguments(
     return args;
 }
 
-interface XPendingReply {
-    messageId: string;
-    owner: string;
-    msSinceLastDelivery: number;
-    deliveriesCounter: number;
-}
-
 export const transformReply = transformReplyStreamMessages;
diff --git a/lib/multi-command.ts b/lib/multi-command.ts
index 8644c81cd9..1454cd22de 100644
--- a/lib/multi-command.ts
+++ b/lib/multi-command.ts
@@ -25,7 +25,7 @@ export interface MultiQueuedCommand {
     transformReply?: RedisCommand['transformReply'];
 }
 
-export type RedisMultiExecutor = (queue: Array<MultiQueuedCommand>, chainId?: Symbol) => Promise<Array<RedisReply>>;
+export type RedisMultiExecutor = (queue: Array<MultiQueuedCommand>, chainId?: symbol) => Promise<Array<RedisReply>>;
 
 export default class RedisMultiCommand<M extends RedisModules = RedisModules, S extends RedisLuaScripts = RedisLuaScripts> {
     static defineCommand(on: any, name: string, command: RedisCommand): void {
diff --git a/lib/test-utils.ts b/lib/test-utils.ts
index 9da6509ff7..0ad10ea0a5 100644
--- a/lib/test-utils.ts
+++ b/lib/test-utils.ts
@@ -217,11 +217,9 @@ export async function spawnRedisCluster(type: TestRedisClusters | null, numberOf
 export async function spawnGlobalRedisCluster(type: TestRedisClusters | null, numberOfNodes: number, args?: Array<string>): Promise<Array<number>> {
     const results = await spawnRedisCluster(type, numberOfNodes, args);
 
-    after(() => {
-        for (const { cleanup } of results) {
-            cleanup();
-        }
-    });
+    after(() => Promise.all(
+        results.map(({ cleanup }) => cleanup())
+    ));
 
     return results.map(({ port }) => port);
 }