diff --git a/netlify.toml b/netlify.toml
index fe8d641ac1..1d0b84a227 100644
--- a/netlify.toml
+++ b/netlify.toml
@@ -20,9 +20,10 @@ function = "version-redirect"
 # with the Hugo version used.
 # see: https://github.com/open-policy-agent/opa/pull/7034
 HUGO_VERSION = "0.113.0"
+# A modern node version is required to build the docusaurus site.
+NODE_VERSION = "22.15.0"
 
 [context.deploy-preview]
-environment = { NODE_VERSION = "22.15.0" }
 command = "make netlify-preview WASM_ENABLED=0 CGO_ENABLED=0"
 
 [context.branch-deploy]