diff --git a/packages/engine-chronocat-api/src/globalVars.ts b/packages/engine-chronocat-api/src/globalVars.ts
new file mode 100644
index 0000000..8de4865
--- /dev/null
+++ b/packages/engine-chronocat-api/src/globalVars.ts
@@ -0,0 +1,12 @@
+import type { Group, Profile, RedIpcData, RedIpcEvent } from '@chronocat/red'
+
+export const requestMethodMap: Record<string, string> = {}
+export const requestCallbackMap: Record<
+  string,
+  (this: RedIpcEvent, detail: RedIpcData) => void
+> = {}
+
+export const groupMap: Record<string, Group> = {}
+export const roleMap: Record<string, Record<string, number>> = {}
+export const friendMap: Record<string, Profile> = {}
+export const richMediaDownloadMap: Record<string, (path: string) => void> = {}
diff --git a/packages/engine-chronocat-api/src/invoke.ts b/packages/engine-chronocat-api/src/invoke.ts
new file mode 100644
index 0000000..05ff90e
--- /dev/null
+++ b/packages/engine-chronocat-api/src/invoke.ts
@@ -0,0 +1,61 @@
+// https://github.com/import-js/eslint-plugin-import/issues/2802
+// eslint-disable-next-line import/no-unresolved
+import { ipcMain } from 'electron'
+import { requestCallbackMap } from './globalVars'
+import type { NtApi } from './types'
+
+export const invoke = async (
+  channel: string,
+  eventName: unknown,
+  ...args: unknown[]
+) => {
+  const uuid = generateUUID()
+  const result = await Promise.race([
+    new Promise((_, reject) => setTimeout(() => reject(), 10000)),
+    new Promise((resolve) => {
+      requestCallbackMap[uuid] = resolve
+      ipcMain.emit(
+        channel,
+        {
+          sender: {
+            send: (...args: unknown[]) => {
+              resolve(args)
+            },
+          },
+        },
+        {
+          type: 'request',
+          callbackId: uuid,
+          eventName,
+        },
+        args,
+      )
+    }),
+  ])
+
+  delete requestCallbackMap[uuid]
+
+  return result
+}
+
+export type Invoke = typeof invoke
+
+export function define<R = undefined, A extends unknown[] = []>(
+  eventName: string,
+  method: string,
+): NtApi<R, A> {
+  return (...args: A) =>
+    invoke('IPC_UP_2', eventName, method, ...args) as Promise<R>
+}
+
+const generateUUID = () => {
+  let d = new Date().getTime()
+  d += performance.now()
+
+  const uuid = 'xxxxxxxx-xxxx-4xxx-8xxx-xxxxxxxxxxxx'.replace(/[xy]/g, (c) => {
+    const r = (d + Math.random() * 16) % 16 | 0
+    d = Math.floor(d / 16)
+    return (c === 'x' ? r : (r & 0x3) | 0x8).toString(16)
+  })
+  return uuid
+}