It appears that the repository has undergone several changes and renamings:

backend/node_modules/reusify/reusify.js

@@ -1,33 +0,0 @@
-'use strict'
-
-function reusify (Constructor) {
-  var head = new Constructor()
-  var tail = head
-
-  function get () {
-    var current = head
-
-    if (current.next) {
-      head = current.next
-    } else {
-      head = new Constructor()
-      tail = head
-    }
-
-    current.next = null
-
-    return current
-  }
-
-  function release (obj) {
-    tail.next = obj
-    tail = obj
-  }
-
-  return {
-    get: get,
-    release: release
-  }
-}
-
-module.exports = reusify