diff --git a/apps/web/src/env.ts b/apps/web/src/env.ts
index 45678b7d..e4f00149 100644
--- a/apps/web/src/env.ts
+++ b/apps/web/src/env.ts
@@ -90,6 +90,7 @@ export const env = createEnv({
     NEXT_PUBLIC_BASE_URL: z.string().url(),
     NEXT_PUBLIC_STORAGE_URL: z.string().url().optional(),
     NEXT_PUBLIC_AVATAR_BUCKET_NAME: z.string().optional(),
+    NEXT_PUBLIC_ATTACHMENTS_BUCKET_NAME: z.string().optional(),
     NEXT_PUBLIC_STORAGE_DOMAIN: z.string().optional(),
     NEXT_PUBLIC_ALLOW_CREDENTIALS: z
       .string()
@@ -125,6 +126,8 @@ export const env = createEnv({
     NEXT_PUBLIC_BASE_URL: process.env.NEXT_PUBLIC_BASE_URL,
     NEXT_PUBLIC_STORAGE_URL: process.env.NEXT_PUBLIC_STORAGE_URL,
     NEXT_PUBLIC_AVATAR_BUCKET_NAME: process.env.NEXT_PUBLIC_AVATAR_BUCKET_NAME,
+    NEXT_PUBLIC_ATTACHMENTS_BUCKET_NAME:
+      process.env.NEXT_PUBLIC_ATTACHMENTS_BUCKET_NAME,
     NEXT_PUBLIC_STORAGE_DOMAIN: process.env.NEXT_PUBLIC_STORAGE_DOMAIN,
     NEXT_PUBLIC_ALLOW_CREDENTIALS: process.env.NEXT_PUBLIC_ALLOW_CREDENTIALS,
     NEXT_PUBLIC_DISABLE_SIGN_UP: process.env.NEXT_PUBLIC_DISABLE_SIGN_UP,
diff --git a/packages/api/package.json b/packages/api/package.json
index df31bb81..7c6e3a0e 100644
--- a/packages/api/package.json
+++ b/packages/api/package.json
@@ -35,6 +35,8 @@
     "typecheck": "tsc --noEmit --emitDeclarationOnly false"
   },
   "dependencies": {
+    "@aws-sdk/client-s3": "^3.802.0",
+    "@aws-sdk/s3-request-presigner": "^3.812.0",
     "@kan/auth": "workspace:*",
     "@kan/db": "workspace:*",
     "@kan/email": "workspace:^",
diff --git a/packages/api/src/utils/s3.ts b/packages/api/src/utils/s3.ts
new file mode 100644
index 00000000..961bb33c
--- /dev/null
+++ b/packages/api/src/utils/s3.ts
@@ -0,0 +1,53 @@
+import {
+  GetObjectCommand,
+  PutObjectCommand,
+  S3Client,
+} from "@aws-sdk/client-s3";
+import { getSignedUrl } from "@aws-sdk/s3-request-presigner";
+
+export function createS3Client() {
+  return new S3Client({
+    region: process.env.S3_REGION ?? "",
+    endpoint: process.env.S3_ENDPOINT ?? "",
+    forcePathStyle: process.env.S3_FORCE_PATH_STYLE === "true",
+    credentials: {
+      accessKeyId: process.env.S3_ACCESS_KEY_ID ?? "",
+      secretAccessKey: process.env.S3_SECRET_ACCESS_KEY ?? "",
+    },
+  });
+}
+
+export async function generateUploadUrl(
+  bucket: string,
+  key: string,
+  contentType: string,
+  expiresIn = 3600,
+) {
+  const client = createS3Client();
+  return getSignedUrl(
+    client,
+    new PutObjectCommand({
+      Bucket: bucket,
+      Key: key,
+      ContentType: contentType,
+      // Don't set ACL for private files
+    }),
+    { expiresIn },
+  );
+}
+
+export async function generateDownloadUrl(
+  bucket: string,
+  key: string,
+  expiresIn = 3600,
+) {
+  const client = createS3Client();
+  return getSignedUrl(
+    client,
+    new GetObjectCommand({
+      Bucket: bucket,
+      Key: key,
+    }),
+    { expiresIn },
+  );
+}
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index 8478c667..2c9d2f0c 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -293,6 +293,12 @@ importers:
 
   packages/api:
     dependencies:
+      '@aws-sdk/client-s3':
+        specifier: ^3.802.0
+        version: 3.879.0
+      '@aws-sdk/s3-request-presigner':
+        specifier: ^3.812.0
+        version: 3.879.0
       '@kan/auth':
         specifier: workspace:*
         version: link:../auth