diff --git a/package.json b/package.json
index f67a3dfb..8ca1604e 100644
--- a/package.json
+++ b/package.json
@@ -13,12 +13,14 @@
     "url": "https://github.com/nodenv/node-build-prerelease/issues"
   },
   "files": [
+    "script",
     "share"
   ],
   "directories": {
-    "test": "./test"
+    "test": "test"
   },
   "scripts": {
+    "postinstall": "script/postinstall",
     "posttest": "npm run lint",
     "lint": "git ls-files bin script **/*.*sh | xargs shellcheck",
     "verify-definitions": "scripty",
diff --git a/script/postinstall b/script/postinstall
new file mode 100755
index 00000000..ce61e13f
--- /dev/null
+++ b/script/postinstall
@@ -0,0 +1,24 @@
+#!/usr/bin/env bash
+
+set -euo pipefail
+IFS=$'\n\t'
+
+installed_by_name() {
+  local pattern='"remain":\["'${npm_package_name-}
+
+  [[ ${npm_config_argv-} =~ $pattern ]]
+}
+
+if [ -n "${npm_config_argv-}" ] && ! installed_by_name; then
+  exit
+fi
+
+cat <<-MSG
+====================
+${npm_package_name-} caveats:
+
+For \`node-build\`/\`nodenv install\` to pick up definitions provided by this plugin,
+ensure '$PWD/share/node-build' exists in NODE_BUILD_DEFINITIONS.
+    export NODE_BUILD_DEFINITIONS="$PWD/share/node-build"
+====================
+MSG