diff --git a/nixos/modules/services/cluster/hadoop/default.nix b/nixos/modules/services/cluster/hadoop/default.nix
index 171d4aced651..41ac46e538e3 100644
--- a/nixos/modules/services/cluster/hadoop/default.nix
+++ b/nixos/modules/services/cluster/hadoop/default.nix
@@ -7,6 +7,7 @@ with lib;
   options.services.hadoop = {
     coreSite = mkOption {
       default = {};
+      type = types.attrsOf types.anything;
       example = literalExample ''
         {
           "fs.defaultFS" = "hdfs://localhost";
@@ -17,6 +18,7 @@ with lib;
 
     hdfsSite = mkOption {
       default = {};
+      type = types.attrsOf types.anything;
       example = literalExample ''
         {
           "dfs.nameservices" = "namenode1";
@@ -27,6 +29,7 @@ with lib;
 
     mapredSite = mkOption {
       default = {};
+      type = types.attrsOf types.anything;
       example = literalExample ''
         {
           "mapreduce.map.cpu.vcores" = "1";
@@ -37,6 +40,7 @@ with lib;
 
     yarnSite = mkOption {
       default = {};
+      type = types.attrsOf types.anything;
       example = literalExample ''
         {
           "yarn.resourcemanager.ha.id" = "resourcemanager1";