This tutorial is a step-by-step guide for people looking to run E2E tests on a large range of physical devices for their React Native Android app.

We will be using AWS Device Farm to do this.

In my previous writeup on the topic of E2E Testing for React Native Android:

I mentioned that:

If you want to run Appium on AWS Device Farm to test your app on real devices, you will need to use Appium Python. They do not support Appium JS.

If you don’t know Python here is a quick tutorial on it:


Follow the official Facebook…

This tutorial is a simple step-by-step guide on how to setup Appium and Jest for React Native Android. I was looking for a step-by-step guide, but had difficulty finding one, so I decided to write my own. Hopefully this can help you out.

Note: This tutorial only covers Android. If you want to run Appium on AWS Device Farm to test your app on real devices, you will need to use Appium Python. They do not support Appium JS. An Appium Python tutorial centered around AWS can be found here.

Appium is a way to automate manual user input for…

I was learning React Server Side Rendering (SSR) recently. Lots of tutorials have so many new libraries and have a large codebase. I often had trouble learning from them. They throw in everything and the kitchen sink, with hot reloading, Redux, Routing, production-ready configs, etc…I just wanted to learn SSR and CSS Modules!

My goal is to strip this tutorial down to the absolute bare essentials you need to get React SSR and CSS Modules working to display a simple page for development. Hopefully, you find this helpful. Let’s get started!

Package Manager

I’m going to be using Yarn instead of NPM…

Meteor is mainly for the web, but what how can we stay up to date when we step away from our desktops and laptops? Having a mobile app version of your webapp can let people get updates through push notifications.

If you’ve never used React Native and Meteor before, you should check out the great tutorials by Spencer Carli on the subject.

Here’s a high level overview of what this guide is going to cover:

  1. Get certificate and key from Apple
  2. Convert certificate and key to .pem format
  3. Test the certificate and key .pem files
  4. Meteor server: Save .pem files

2017–11–23 Note: MongoChef is now called Studio 3T.

I had to do this recently, so I’m putting down what I learned in one place in case anyone needs it too.

Here’s the high level overview of what this article is about.

  1. Connecting to Mongo
  2. Backing up your database
  3. Restoring your database

Connecting to Mongo

This guide will be using MongoChef; a GUI for managing your Mongo databases. You can download it here: It’s free for personal use.

mupx actually sets up your Meteor app in a Docker container so you actually can’t access the Mongo database directly. mupx docs say:


I recently started to adopt the Mantra application architecture for my Meteor 1.3 apps. Mantra is still in it’s early stages (0.2.0) so I ran into a situation that the spec and the current examples didn’t cover.

Prior to Meteor 1.3, I would just keep all the <head> stuff in an html file in /client/index.html. But we have no index.html in Mantra anymore. What do we do?

It’s a pretty simple solution. Kadira comes to the rescue with their Meteor package; DocHead.

First, add the Meteor package.

meteor add kadira:dochead

Then in a file on the client side:

// /client/main.js

Heyse Li

Friendly neighborhood dev:

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