diff --git a/apps/server/src/providers/filesystem-storage.provider.ts b/apps/server/src/providers/filesystem-storage.provider.ts
index 72ebce8..c16024b 100644
--- a/apps/server/src/providers/filesystem-storage.provider.ts
+++ b/apps/server/src/providers/filesystem-storage.provider.ts
@@ -1,5 +1,6 @@
 import { env } from "../env";
 import { StorageProvider } from "../types/storage";
+import { IS_RUNNING_IN_CONTAINER } from "../utils/container-detection";
 import * as crypto from "crypto";
 import * as fsSync from "fs";
 import * as fs from "fs/promises";
@@ -15,25 +16,12 @@ export class FilesystemStorageProvider implements StorageProvider {
   private downloadTokens = new Map<string, { objectName: string; expiresAt: number; fileName?: string }>();
 
   private constructor() {
-    this.uploadsDir = this.isDocker() ? "/app/server/uploads" : path.join(process.cwd(), "uploads");
+    this.uploadsDir = IS_RUNNING_IN_CONTAINER ? "/app/server/uploads" : path.join(process.cwd(), "uploads");
 
     this.ensureUploadsDir();
     setInterval(() => this.cleanExpiredTokens(), 5 * 60 * 1000);
   }
 
-  private isDocker(): boolean {
-    try {
-      fsSync.statSync("/.dockerenv");
-      return true;
-    } catch {
-      try {
-        return fsSync.readFileSync("/proc/self/cgroup", "utf8").includes("docker");
-      } catch {
-        return false;
-      }
-    }
-  }
-
   public static getInstance(): FilesystemStorageProvider {
     if (!FilesystemStorageProvider.instance) {
       FilesystemStorageProvider.instance = new FilesystemStorageProvider();
@@ -229,8 +217,10 @@ export class FilesystemStorageProvider implements StorageProvider {
     if (encryptedBuffer.length > 16) {
       try {
         return this.decryptFileBuffer(encryptedBuffer);
-      } catch (error) {
-        console.warn("Failed to decrypt with new method, trying legacy format");
+      } catch (error: unknown) {
+        if (error instanceof Error) {
+          console.warn("Failed to decrypt with new method, trying legacy format", error.message);
+        }
         return this.decryptFileLegacy(encryptedBuffer);
       }
     }
diff --git a/apps/server/src/server.ts b/apps/server/src/server.ts
index ecc6084..e8d1b7c 100644
--- a/apps/server/src/server.ts
+++ b/apps/server/src/server.ts
@@ -11,9 +11,9 @@ import { reverseShareRoutes } from "./modules/reverse-share/routes";
 import { shareRoutes } from "./modules/share/routes";
 import { storageRoutes } from "./modules/storage/routes";
 import { userRoutes } from "./modules/user/routes";
+import { IS_RUNNING_IN_CONTAINER } from "./utils/container-detection";
 import fastifyMultipart from "@fastify/multipart";
 import fastifyStatic from "@fastify/static";
-import * as fsSync from "fs";
 import * as fs from "fs/promises";
 import crypto from "node:crypto";
 import path from "path";
@@ -27,21 +27,7 @@ if (typeof global.crypto === "undefined") {
 }
 
 async function ensureDirectories() {
-  // Use /app/server paths in Docker, current directory for local development
-  const isDocker = (() => {
-    try {
-      fsSync.statSync("/.dockerenv");
-      return true;
-    } catch {
-      try {
-        return fsSync.readFileSync("/proc/self/cgroup", "utf8").includes("docker");
-      } catch {
-        return false;
-      }
-    }
-  })();
-
-  const baseDir = isDocker ? "/app/server" : process.cwd();
+  const baseDir = IS_RUNNING_IN_CONTAINER ? "/app/server" : process.cwd();
   const uploadsDir = path.join(baseDir, "uploads");
   const tempChunksDir = path.join(baseDir, "temp-chunks");
 
@@ -78,20 +64,7 @@ async function startServer() {
   });
 
   if (env.ENABLE_S3 !== "true") {
-    const isDocker = (() => {
-      try {
-        fsSync.statSync("/.dockerenv");
-        return true;
-      } catch {
-        try {
-          return fsSync.readFileSync("/proc/self/cgroup", "utf8").includes("docker");
-        } catch {
-          return false;
-        }
-      }
-    })();
-
-    const baseDir = isDocker ? "/app/server" : process.cwd();
+    const baseDir = IS_RUNNING_IN_CONTAINER ? "/app/server" : process.cwd();
     const uploadsPath = path.join(baseDir, "uploads");
 
     await app.register(fastifyStatic, {
diff --git a/apps/server/src/utils/container-detection.ts b/apps/server/src/utils/container-detection.ts
new file mode 100644
index 0000000..a079422
--- /dev/null
+++ b/apps/server/src/utils/container-detection.ts
@@ -0,0 +1,45 @@
+import * as fsSync from "fs";
+
+/**
+ * Determines if the application is running inside a container environment.
+ * Checks common container indicators like /.dockerenv and cgroup file patterns.
+ *
+ * This function caches its result after the first call for performance.
+ *
+ * @returns {boolean} True if running in a container, false otherwise.
+ */
+function isRunningInContainer(): boolean {
+  try {
+    if (fsSync.existsSync("/.dockerenv")) {
+      return true;
+    }
+
+    const cgroupContent = fsSync.readFileSync("/proc/self/cgroup", "utf8");
+    const containerPatterns = [
+      "docker",
+      "containerd",
+      "lxc",
+      "kubepods",
+      "pod",
+      "/containers/",
+      "system.slice/container-",
+    ];
+
+    for (const pattern of containerPatterns) {
+      if (cgroupContent.includes(pattern)) {
+        return true;
+      }
+    }
+
+    if (fsSync.existsSync("/.well-known/container")) {
+      return true;
+    }
+  } catch (e: unknown) {
+    if (e instanceof Error) {
+      console.warn("Could not perform full container detection:", e.message);
+    }
+  }
+  return false;
+}
+
+export const IS_RUNNING_IN_CONTAINER = isRunningInContainer();