Add service.healthcheck.start_period option

docs/modules/ROOT/partials/NixOSOptions.adoc

@@ -707,6 +707,28 @@ Default::
 
 No Example:: {blank}
 
+== services.<name>.service.healthcheck.start_period
+
+See link:https://docs.docker.com/compose/compose-file/#healthcheck[Docker Compose#healthcheck]
+
+[discrete]
+=== details
+
+Type:: string
+Default::
++
+----
+"0s"
+----
+
+
+Example::
++
+----
+"30s"
+----
+
+
 == services.<name>.service.healthcheck.test
 
 See link:https://docs.docker.com/compose/compose-file/#healthcheck[Docker Compose#healthcheck]

src/nix/modules/service/docker-compose-service.nix

@@ -123,6 +123,12 @@ in
       example = "10s";
       description = dockerComposeRef "healthcheck";
     };
+    service.healthcheck.start_period = mkOption {
+      type = str;
+      default = "0s";
+      example = "30s";
+      description = dockerComposeRef "healthcheck";
+    };
     service.healthcheck.retries = mkOption {
       type = int;
       default = 3;