diff --git a/doc/clickhouse.md b/doc/clickhouse.md
index 01b1e6c..36ae0e7 100644
--- a/doc/clickhouse.md
+++ b/doc/clickhouse.md
@@ -23,9 +23,9 @@ Clickhouse has [HTTP Interface](https://clickhouse.com/docs/en/interfaces/http)
 {
   services.clickhouse."clickhouse-1" = {
     enable = true;
-    extraConfig = ''
-      http_port: 9050
-    '';
+    extraConfig = {
+      http_port = 9050
+    };
   };
 }
 ```
diff --git a/nix/clickhouse/clickhouse_test.nix b/nix/clickhouse/clickhouse_test.nix
index d9a230e..bf2f7cc 100644
--- a/nix/clickhouse/clickhouse_test.nix
+++ b/nix/clickhouse/clickhouse_test.nix
@@ -2,16 +2,12 @@
   services.clickhouse."clickhouse1" = {
     enable = true;
     port = 9000;
-    extraConfig = ''
-      http_port: 9050
-    '';
+    extraConfig.http_port = 9050;
   };
   services.clickhouse."clickhouse2" = {
     enable = true;
     port = 9001;
-    extraConfig = ''
-      http_port: 9051
-    '';
+    extraConfig.http_port = 9051;
     initialDatabases = [
       {
         name = "sample_db";
diff --git a/nix/clickhouse/default.nix b/nix/clickhouse/default.nix
index 2be00e9..fc8385e 100644
--- a/nix/clickhouse/default.nix
+++ b/nix/clickhouse/default.nix
@@ -2,6 +2,7 @@
 { pkgs, lib, name, config, ... }:
 let
   inherit (lib) types;
+  yamlFormat = pkgs.formats.yaml { };
 in
 {
   options = {
@@ -27,9 +28,9 @@ in
     };
 
     extraConfig = lib.mkOption {
-      type = types.lines;
+      type = yamlFormat.type;
       description = "Additional configuration to be appended to `clickhouse-config.yaml`.";
-      default = "";
+      default = { };
     };
 
     initialDatabases = lib.mkOption {
@@ -73,22 +74,26 @@ in
       default = {
         processes =
           let
-            clickhouseConfig = pkgs.writeText "clickhouse-config.yaml" ''
-              logger:
-                level: warning
-                console: 1
-              tcp_port: ${toString config.port}
-              default_profile: default
-              default_database: default
-              path: ${config.dataDir}/clickhouse
-              tmp_path: ${config.dataDir}/clickhouse/tmp
-              user_files_path: ${config.dataDir}/clickhouse/user_files
-              format_schema_path: ${config.dataDir}/clickhouse/format_schemas
-              user_directories:
-                users_xml:
-                  path: ${config.package}/etc/clickhouse-server/users.xml
-              ${config.extraConfig}
-            '';
+            clickhouseConfig = yamlFormat.generate "clickhouse-config.yaml" (
+              {
+                logger = {
+                  level = "warning";
+                  console = 1;
+                };
+                tcp_port = "${toString config.port}";
+                default_profile = "default";
+                default_database = "default";
+                path = "${config.dataDir}/clickhouse";
+                tmp_path = "${config.dataDir}/clickhouse/tmp";
+                user_files_path = "${config.dataDir}/clickhouse/user_files";
+                format_schema_path = "${config.dataDir}/clickhouse/format_schemas";
+                user_directories = {
+                  users_xml = {
+                    path = "${config.package}/etc/clickhouse-server/users.xml";
+                  };
+                };
+              } // config.extraConfig
+            );
           in
           {
             # DB initialization