Introduce better instructions for Ubuntu development environment

README.md

@@ -185,7 +185,20 @@ If you're comfortable getting up and running from a `git clone`, this method is
 4. `npm run sencha:compile`
 5. `npm start`
 
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+#### Compile on Ubuntu:
+
+These instructions were tested with Ubuntu 17.04.
+1. Install dependencies: `sudo apt install nodejs-legacy npm git`
+2. Build and install electron: `sudo npm install electron-prebuilt -g`
+3. Install Sencha Cmd (non-free): https://www.sencha.com/products/extjs/cmd-download/
+4. Clone repository: `git clone https://github.com/saenzramiro/rambox.git`
+5. Install npm dependencies: `npm install`
+6. Configure `env-sample.js` and rename it to `env.js`.
+7. Compile: `npm run sencha:compile`
+8. Start program: `npm start`
+
+
+-------------------
 
 Disclosure
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