diff --git a/packages/chopsticks/src/server.ts b/packages/chopsticks/src/server.ts
index 1e0e7a66..901ce44e 100644
--- a/packages/chopsticks/src/server.ts
+++ b/packages/chopsticks/src/server.ts
@@ -1,6 +1,6 @@
+import { AddressInfo, WebSocket, WebSocketServer } from 'ws'
 import { ResponseError, SubscriptionManager } from '@acala-network/chopsticks-core'
 import { z } from 'zod'
-import WebSocket, { AddressInfo, WebSocketServer } from 'ws'
 
 import { defaultLogger, truncate } from './logger'
 
diff --git a/packages/core/src/api.ts b/packages/core/src/api.ts
index 6b558930..17760b78 100644
--- a/packages/core/src/api.ts
+++ b/packages/core/src/api.ts
@@ -62,10 +62,12 @@ export class Api {
         this.#ready = this.#provider['isReady']
       } else {
         this.#ready = new Promise((resolve): void => {
-          this.#provider.on('connected', (): void => {
+          if (this.#provider.hasSubscriptions) {
+            this.#provider.on('connected', resolve)
+            this.#provider.connect()
+          } else {
             resolve()
-          })
-          this.#provider.connect()
+          }
         })
       }
     }
diff --git a/packages/core/src/setup.ts b/packages/core/src/setup.ts
index 591874cf..dae2ed2d 100644
--- a/packages/core/src/setup.ts
+++ b/packages/core/src/setup.ts
@@ -1,8 +1,8 @@
 import '@polkadot/types-codec'
 import { HexString } from '@polkadot/util/types'
+import { HttpProvider, WsProvider } from '@polkadot/rpc-provider'
 import { ProviderInterface } from '@polkadot/rpc-provider/types'
 import { RegisteredTypes } from '@polkadot/types/types'
-import { WsProvider } from '@polkadot/rpc-provider'
 
 import { Api } from './api'
 import { Blockchain } from './blockchain'
@@ -37,6 +37,8 @@ export const setup = async (options: SetupOptions) => {
   let provider: ProviderInterface
   if (options.genesis) {
     provider = options.genesis
+  } else if (/^(https|http):\/\//.test(options.endpoint || '')) {
+    provider = new HttpProvider(options.endpoint)
   } else {
     provider = new WsProvider(options.endpoint)
   }
diff --git a/packages/e2e/src/batch-request.test.ts b/packages/e2e/src/batch-request.test.ts
index e5e3c54e..d968cbae 100644
--- a/packages/e2e/src/batch-request.test.ts
+++ b/packages/e2e/src/batch-request.test.ts
@@ -1,5 +1,5 @@
+import { WebSocket } from 'ws'
 import { afterAll, beforeAll, describe, expect, it } from 'vitest'
-import WebSocket from 'ws'
 
 import networks from './networks'
 
diff --git a/packages/e2e/src/build-block.test.ts b/packages/e2e/src/build-block.test.ts
index 576e73af..c6bc5175 100644
--- a/packages/e2e/src/build-block.test.ts
+++ b/packages/e2e/src/build-block.test.ts
@@ -13,7 +13,7 @@ const KUSAMA_STORAGE = {
 }
 
 describe.runIf(process.env.CI).each([
-  { chain: 'Polkadot', endpoint: 'wss://rpc.polkadot.io' },
+  { chain: 'Polkadot', endpoint: 'https://rpc.polkadot.io' },
   { chain: 'Statemint', endpoint: 'wss://statemint-rpc.polkadot.io' },
   { chain: 'Polkadot Collectives', endpoint: 'wss://polkadot-collectives-rpc.polkadot.io' },
   { chain: 'Acala', endpoint: 'wss://acala-rpc-1.aca-api.network' },
diff --git a/packages/e2e/src/helper.ts b/packages/e2e/src/helper.ts
index fc077377..ad301612 100644
--- a/packages/e2e/src/helper.ts
+++ b/packages/e2e/src/helper.ts
@@ -1,6 +1,7 @@
-import { ApiPromise, WsProvider } from '@polkadot/api'
+import { ApiPromise, HttpProvider, WsProvider } from '@polkadot/api'
 import { Codec, RegisteredTypes } from '@polkadot/types/types'
 import { HexString } from '@polkadot/util/types'
+import { ProviderInterface } from '@polkadot/rpc-provider/types'
 import { beforeAll, beforeEach, expect, vi } from 'vitest'
 
 import { Api } from '@acala-network/chopsticks'
@@ -58,7 +59,15 @@ export const setupAll = async ({
   registeredTypes = {},
   runtimeLogLevel,
 }: SetupOption) => {
-  const api = new Api(genesis ? await genesisFromUrl(genesis) : new WsProvider(endpoint), {
+  let provider: ProviderInterface
+  if (genesis) {
+    provider = await genesisFromUrl(genesis)
+  } else if (/^(https|http):\/\//.test(endpoint || '')) {
+    provider = new HttpProvider(endpoint)
+  } else {
+    provider = new WsProvider(endpoint)
+  }
+  const api = new Api(provider, {
     SetEvmOrigin: { payload: {}, extrinsic: {} },
   })