diff --git a/hosts/nachtigall/apps/matrix/synapse.nix b/hosts/nachtigall/apps/matrix/synapse.nix
index 050cad2..1c76e1d 100644
--- a/hosts/nachtigall/apps/matrix/synapse.nix
+++ b/hosts/nachtigall/apps/matrix/synapse.nix
@@ -15,6 +15,12 @@ in {
     owner = "matrix-synapse";
   };
 
+  age.secrets."matrix-synapse-sliding-sync-secret" = {
+    file = "${flake.self}/secrets/matrix-synapse-sliding-sync-secret.age";
+    mode = "400";
+    owner = "matrix-synapse";
+  };
+
   services.matrix-synapse = {
     enable = true;
     settings = {
@@ -226,6 +232,18 @@ in {
     plugins = [
       config.services.matrix-synapse.package.plugins.matrix-synapse-shared-secret-auth
     ];
+
+    sliding-sync = {
+      enable = true;
+      settings = {
+        SYNCV3_SERVER = "https://${publicDomain}";
+        SYNCV3_BINDADDR = "127.0.0.1:8011";
+        # The bind addr for Prometheus metrics, which will be accessible at
+        # /metrics at this address
+        SYNCV3_PROM = "127.0.0.1:9100";
+      };
+      environmentFile = config.age.secrets."matrix-synapse-sliding-sync-secret".path;
+    };
   };
 
   services.restic.backups.matrix-synapse-storagebox = {
diff --git a/hosts/nachtigall/apps/nginx-matrix.nix b/hosts/nachtigall/apps/nginx-matrix.nix
index ef4ee28..5dd3c48 100644
--- a/hosts/nachtigall/apps/nginx-matrix.nix
+++ b/hosts/nachtigall/apps/nginx-matrix.nix
@@ -9,7 +9,7 @@ let
   wellKnownClient = domain: {
     "m.homeserver".base_url = "https://matrix.${domain}";
     "m.identity_server".base_url = "https://matrix.${domain}";
-    "org.matrix.msc3575.proxy".url = "https://matrix.${domain}/sliding-sync";
+    "org.matrix.msc3575.proxy".url = "https://matrix.${domain}";
     "im.vector.riot.e2ee".default = true;
     "io.element.e2ee" = {
       default = true;
@@ -98,6 +98,12 @@ in
           extraConfig = commonHeaders;
         };
 
+        # sliding-sync
+        "~ ^/(client/|_matrix/client/unstable/org.matrix.msc3575/sync)" = {
+          proxyPass = "http://127.0.0.1:8011";
+          extraConfig = commonHeaders;
+        };
+
         "~* ^(/_matrix|/_synapse/client|/_synapse/oidc)" = {
           proxyPass = "http://127.0.0.1:8008";
 
diff --git a/secrets/matrix-synapse-sliding-sync-secret.age b/secrets/matrix-synapse-sliding-sync-secret.age
new file mode 100644
index 0000000..966eb28
--- /dev/null
+++ b/secrets/matrix-synapse-sliding-sync-secret.age
@@ -0,0 +1,27 @@
+age-encryption.org/v1
+-> ssh-ed25519 iDKjwg O7ax7BWOp2BEKA9i4WAmI0hsGoRjSzfAbMb4eRLdoRM
+LlddBgKAoFe7qKvq7ixIphiWiO1JzKSyLJ6PSmUd2xA
+-> ssh-ed25519 uYcDNw 5gN/+TZa94jPsMsrwXlrb1U8alMnCJq5/EIegIus0SI
+NUTWQw6WCZTpKK4EFBL1lxSSnI9WEAb1MB7iFiezDFg
+-> ssh-rsa kFDS0A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+-> ssh-ed25519 YFSOsg nvVCR2LV8DHU+hIQa19uX9pEhA+NQxMkmBUMDktKOGU
+Q9qhrcOeEA3myMqZbptbsWCS9hbm67pF5qO3jARN/bs
+-> ssh-ed25519 iHV63A +Pca506lCnqn/+2e3lKVzlLcsa63EgngYry54yiAxA0
+hyZZUoRuYjJvhznZBAkRRjq2x6jZvJX0sfj+jigX39c
+-> ssh-ed25519 BVsyTA hza+5wLH7L3VyXIwBK/sq5UNR6SC3EnKxQ3ucrVPwXc
+BAXKAf2gdMT29ZXEAeq0B54ojrGa9LwfhBK91v68yis
+-> !By"-grease
+7r6wODXXipdv7nXJ+K653PLYdKOLF1pEvCWeKk8/q49s5ScMqZpGVA
+--- zNjNg84OVHL/CbJyutcBz6eWD+71peLb7weZ/EjQaic
+r!�?RU��o�E��~W�>_��t��=�*7��t�=
QԹ�[`@�B۝�jedܰ��q��o^���P���N���{H�^���j���B�h�:PP��&♗mܯt
\ No newline at end of file
diff --git a/secrets/secrets.nix b/secrets/secrets.nix
index 712839d..21e7a52 100644
--- a/secrets/secrets.nix
+++ b/secrets/secrets.nix
@@ -44,6 +44,7 @@ in {
   "matrix-mautrix-telegram-env-file.age".publicKeys = nachtigallKeys ++ baseKeys;
   "matrix-synapse-signing-key.age".publicKeys = nachtigallKeys ++ baseKeys;
   "matrix-synapse-secret-config.yaml.age".publicKeys = nachtigallKeys ++ baseKeys;
+  "matrix-synapse-sliding-sync-secret.age".publicKeys = nachtigallKeys ++ baseKeys;
 
   "nextcloud-secrets.age".publicKeys = nachtigallKeys ++ baseKeys;
   "nextcloud-admin-pass.age".publicKeys = nachtigallKeys ++ baseKeys;