replace app with discourse module

README.md

@@ -0,0 +1,28 @@
+# TIDE
+
+TIDE is the NixOS module for the Torah Im Derech Eretz forum. It deploys the
+forum with NixOS Discourse and configures its production Borg backup.
+
+## NixOS module
+
+Import `nixosModules.tide` or `nixosModules.default`, then provide the runtime
+secret paths:
+
+```nix
+services.tide = {
+  enable = true;
+  secretFiles = {
+    adminPassword = "/run/secrets/tide-admin-password";
+    mailPassword = "/run/secrets/tide-mail-password";
+    secretKeyBase = "/run/secrets/tide-secret-key-base";
+    borgPassphrase = "/run/secrets/borg-passphrase";
+    borgPrivateKey = "/run/secrets/borg-private-key";
+  };
+};
+```
+
+The module owns the forum hostname, site identity, SMTP configuration, and
+backup policy. The importing host owns secret provisioning.
+
+See [RECOVERY.md](./RECOVERY.md) for the database and state restoration
+procedure.