diff --git a/lib/package-envs.js b/lib/package-envs.js
index 72185f2..44005cb 100644
--- a/lib/package-envs.js
+++ b/lib/package-envs.js
@@ -1,19 +1,19 @@
 // https://github.com/npm/rfcs/pull/183
 
-const envVal = val => Array.isArray(val) ? val.map(v => envVal(v)).join('\n\n')
-  : val === null || val === false ? ''
-  : String(val)
+const envVal = val => val === null || val === false ? '' : String(val)
 
 const packageEnvs = (env, vals, prefix) => {
   for (const [key, val] of Object.entries(vals)) {
     if (val === undefined) {
       continue
-    } else if (val && !Array.isArray(val) && typeof val === 'object') {
-      packageEnvs(env, val, `${prefix}${key}_`)
-    } else if (Array.isArray(val)) {
-      val.forEach((item, index) => {
-        env[`${prefix}${key}_${index}`] = envVal(item)
-      })
+    } else if (val && typeof val === 'object') {
+      if (Array.isArray(val)) {
+        val.forEach((item, index) => {
+          packageEnvs(env, { [`${key}_${index}`]: item }, `${prefix}`)
+        })
+      } else {
+        packageEnvs(env, val, `${prefix}${key}_`)
+      }
     } else {
       env[`${prefix}${key}`] = envVal(val)
     }