diff --git a/index.ts b/index.ts
index b7ce08d..7bfbae3 100644
--- a/index.ts
+++ b/index.ts
@@ -4,7 +4,7 @@ import path from "path"
 import { MatrixBotClient } from "./matrix-client.js"
 import { SessionManager } from "./session-manager.js"
 import { loadConfig } from "./config-loader.js"
-import { log } from "./logger.js"
+import { setLogDir, log } from "./logger.js"
 
 log("Plugin module loaded")
 
@@ -73,6 +73,7 @@ async function runPlugin(ctx: any, options: any) {
   LOCK_FILE = `${dataDir}/lock`
   const SETUP_STARTED_LOG = `${dataDir}/setup-started.log`
   const SETUP_ERROR_LOG = `${dataDir}/setup-error.log`
+  setLogDir(dataDir)
 
   // Acquire global lock — only one instance (server or client) starts the bot
   const locked = tryAcquireLock()
diff --git a/logger.ts b/logger.ts
index a780dae..0c4690f 100644
--- a/logger.ts
+++ b/logger.ts
@@ -1,8 +1,14 @@
 import fs from "fs"
+import os from "os"
 import path from "path"
 
-const LOG_DIR = "/tmp/opencode-matrix-plugin"
-const LOG_FILE = path.join(LOG_DIR, "plugin.log")
+let LOG_DIR = "/tmp/opencode-matrix-plugin"
+let LOG_FILE = path.join(LOG_DIR, "plugin.log")
+
+export function setLogDir(dir: string): void {
+  LOG_DIR = dir
+  LOG_FILE = path.join(dir, "plugin.log")
+}
 
 export function log(message: string): void {
   try {