diff --git a/opentech/static_src/package.json b/opentech/static_src/package.json
index be07c744c4a68b2606a8326e12c3688eeb73d720..267a0576789ec7052f3dc5581fae9844841e307a 100755
--- a/opentech/static_src/package.json
+++ b/opentech/static_src/package.json
@@ -97,7 +97,7 @@
     "sass-lint": "^1.12.1"
   },
   "engines": {
-    "node": ">=8.0.0 <9.0.0"
+    "node": "8.12.0"
   },
   "dependencies": {
     "@fancyapps/fancybox": "^3.2.5"
diff --git a/package.json b/package.json
index df087836679dd837745ba978227ef2a1a4f584e4..217a9ec2e31b783b6aa264d61be68b7e3a81eb24 100644
--- a/package.json
+++ b/package.json
@@ -7,7 +7,7 @@
         "heroku-postbuild": "cd opentech/static_src && yarn install && npm run build:prod"
     },
     "engines": {
-        "node": ">=8.0.0 <9.0.0",
-        "yarn": "^1.7.0"
+        "node": "8.12.0",
+        "yarn": "1.10.0"
     }
 }