add backup guide

docs/malta.config.json

@@ -7,7 +7,10 @@
     "sidebar": [
         {
             "title": "Faroe server",
-            "pages": [["Getting started", "/faroe-server/getting-started"]]
+            "pages": [
+                ["Getting started", "/faroe-server/getting-started"],
+                ["Database backup", "/faroe-server/database-backup"]
+            ]
         },
         {
             "title": "Email and password",

docs/pages/faroe-server/database-backup.md

@@ -0,0 +1,21 @@
+---
+title: "Database backup"
+---
+
+# Database backup
+
+Faroe does not backup its SQLite database. We recommend using [Litestream](https://litestream.io) to create database replicas locally or externally in services like S3.
+
+Use the `replicate` command to create a replica. Faroe should be ran as a child process using the `exec` option.
+
+```
+litestream replicate -exec="./faroe serve" faroe_data/sqlite.db file://backup
+```
+
+Use the `restore` command to restore the database from a replica.
+
+```
+litestream restore -o faroe_data/sqlite.db file://backup 
+rm sqlite.db.tmp-shm
+sqlite.db.tmp-wal
+```