diff --git a/docs/3.x.x/configurations/configurations.md b/docs/3.x.x/configurations/configurations.md
index 7aaf82b360..9436777cb2 100644
--- a/docs/3.x.x/configurations/configurations.md
+++ b/docs/3.x.x/configurations/configurations.md
@@ -130,6 +130,26 @@ module.exports = {
 };
 ```
 
+### Bookshelf, Mongoose
+
+**Path —** `./config/functions/bookshelf.js`.
+**Path —** `./config/functions/mongoose.js`.
+
+When present, they are loaded to let you customize your database connection instance, for example for adding some plugin, customizing parameters, etc.
+
+As an example, for using the `mongoose-simple-random` plugin for MongoDB, you can register it like this:
+
+**Path —** `./config/functions/mongoose.js`.
+```js
+'use strict';
+
+const random = require('mongoose-simple-random');
+
+module.exports = (mongoose, connection) => {
+  mongoose.plugin(random);
+};
+```
+
 ***
 
 ## Locales
diff --git a/packages/strapi-hook-bookshelf/lib/index.js b/packages/strapi-hook-bookshelf/lib/index.js
index af4effbf10..c4e6b7a533 100644
--- a/packages/strapi-hook-bookshelf/lib/index.js
+++ b/packages/strapi-hook-bookshelf/lib/index.js
@@ -60,7 +60,7 @@ module.exports = function(strapi) {
             'config',
             'functions',
             'bookshelf.js'
-          ))(ORM, strapi.connections[connectionName]);
+          ))(ORM, connection);
         } catch (err) {
           // This is not an error if the file is not found.
         }
diff --git a/packages/strapi-hook-mongoose/lib/index.js b/packages/strapi-hook-mongoose/lib/index.js
index fd97747958..7725657fe0 100644
--- a/packages/strapi-hook-mongoose/lib/index.js
+++ b/packages/strapi-hook-mongoose/lib/index.js
@@ -6,6 +6,7 @@
 
 // Public node modules.
 const url = require('url');
+const path = require('path');
 const _ = require('lodash');
 const mongoose = require('mongoose');
 const Mongoose = mongoose.Mongoose;
@@ -89,6 +90,18 @@ module.exports = function (strapi) {
           return cb(errMsg);
         }
 
+        try {
+          // Require `config/functions/mongoose.js` file to customize connection.
+          require(path.resolve(
+            strapi.config.appPath,
+            'config',
+            'functions',
+            'mongoose.js'
+          ))(instance, connection);
+        } catch (err) {
+          // This is not an error if the file is not found.
+        }
+
         Object.keys(options, key => instance.set(key, options[key]));
 
         const mountModels = (models, target, plugin = false) => {